# Amicus Curiae Brief — Bragdon v. Abbott > Briefs, arguments, decisions, and more. URL: https://www.frixlaw.com/law-library/documents/brief%3Amicro_IA40386018_1497%3A4 ## Record - **Collection:** Supreme Court brief - **Document type:** Amicus Curiae Brief - **Published:** January 1, 1999 - **Citation:** 526 U.S. 1131 ## Text Sl Supreme Court, U. S, (A "its fs APR 23 1999 No. 98-1536 CLERK In The this Supreme Court of the United States October Term, 1998 + RANDON BRAGDON, D.M.D., Petitioner, SIDNEY ABBOTT, et al., Respondents. * On Petition For A Writ Of Certiorari To The United States Court Of Appeals For The First Circuit + BRIEF OF THE AMICUS CURIAE CLINICAL RESEARCH ASSOCIATES IN SUPPORT OF RANDON BRAGDON, D.M.D., PETITIONER ¢ RicHarp L. Hit, Esa. Counsel of Record for Amicus Curiae, Clinical Research Associates Hitt, JOHNSON & ScHumMTz, P.C. Jamestown Square 3319 North University Avenue Suite 200 Provo, Utah 84604 (801) 375-6600 COCKLE LAW BRIEF PRINTING CO., (800) 225-6964 OR CALL COLLECT (402) 342-2831 i TABLE OF CONTENTS STATEMENT OF INTEREST OF AMICUS CURIAE.. 1 SUMMARY OF ARGUMENT....................... y ih oc Re CERIN Sra 3 THE UNIVERSAL PRECAUTIONS CONCEPT DOES NOT ALLEVIATE SIGNIFICANT RISK TO CAREGIVERS DURING TREATMENT OF INFEC- TIOUS PATIENTS BECAUSE THE PRODUCTS NECESSARY TO IMPLEMENT THE CONCEPT OFTEN FAIL THEIR INTENDED PURPOSE...... 3 PO MOR Rey Co ce Oey ee 7 Latex Examination Glove SONY 5 Po 9 Environmental Surface Disinfectants ........... 11 Instrument Immersion Disinfectants............ 14 Sterilization Equipment......................__ 15 SWE PeR MMNn chia k tevuiati occas wick 17 APPENDIX INDEX Knox, Richard A., A Nurse Hopes Her Infection Will Spur Action, Boston Globe, (April 6, 1999) (Ref- ap edie: at ERE PONS ET OH ERE tna rt ied App. 1 United States General Accounting Office, Report to Congressional Requesters, GAO/RCED-90-139, DISINFECTANTS: EPA Lacks Assurance They Work (August 1990) (Reference RW ahs hays App. 5 il TABLE OF CONTENTS - Continued Page Altman, Lawrence K, M.D., New York Times, Investigating a Medical Maze: Virus Transmission in Surgery — Hepatitis B was Apparently Spread by a Doctor, but How?, New York Times (March 22, 1994): (Reference. No. 3)... Save cc evaaeewcen) App. 14 Harpaz, Seidlein, Averhoff, Tormey, Sinha, Kot- sopoulou, Lambert, Robertson, Cherry and Shapiro, Transmission of Hepatitis B Virus to Mul- tiple Patients from a Surgeon Without Evidence of Inadequate Infection Control, The New England Journal of Medicine, Volume 334, Number 9 (February 29, 1996) (Reference No. 4)........ App. 21 Christensen, Robison, Robinson, Ploeger, and Leavitt, Efficiency of 42 Brands of FaceMasks and 2 Face Shields in Preventing Inhalation of Airborne Debris, General Dentistry (November-December 1991) (Reference .No. She. jase hckeeecteeenn’ App. 41 Clinical Research Associates, SUBJECT: Operating Gloves, Important New Trends, CRA Newsletter Volume 19, Issue 9 (September 1995) (Reference IG, Oi ccs acawdhcee ce ek eee ee App. 57 Clinical Research Associates, SUBJECT: Gloves, Non-Sterile Operating, Update Review, CRA Newsletter, Volume 16, Issue 10 (October 1992) (Raetewenee ING. 2)... esses ck cecw van cane mer ues App. 61 Clinical Research Associates, SUBJECT: Gloves, Non-Sterile Latex, CRA Newsletter Volume 15, Issue 9 (September 1991) (Reference No. 8) App. 67 Clinical Research Associates, SUBJECT: Operating Gloves, Update, CRA Newsletter Volume 13, Issue 1 (January 1989) (Reference No. 9)....App. 73 we ny cen AI Dt NR ol aN st hl A Ay lh Sa DSS ME ee Cae ee RICH ert OS Mave nl Sh aE Saal Be wet tt ma! ee iii TABLE OF CONTENTS - Continued Page Korniewicz, Laughon, Cyr, Lytle, and Larson, Leakage of Virus through Used Vinyl and Latex Examination Gloves, Journal of Clinical Micro- biology, pp. 787-788 (April 1990) (Reference No. ERY ee Sh aoe ae Sahay a ae a a App. 78 Mbithi, Springthorpe, Boulet, and Sattar, Survival of Hepatitis A Virus on Human Hands and Its Transfer on Contact with Animate and Inanimate Surfaces, Journal of Clinical Microbiology, pp. 757-763, (April 1992) (Reference No. 11) ....App. 85 Gwaltney and Hendley, Transmission of Experimen- tal Rhinovirus Infection by Contaminated Services, American Journal of Epidemiology (1982) (Ref- WOE POO MME Wiss 660s GeV 50h bid oiek Lk, App. 109 Letter to the Editor, Inactivation of Human Immu- nodeficiency Virus-1 at Short Time Intervals Using Undiluted Bleach, Journal of Acquired Immune Deficiency Syndromes, Volume 6, Number rs bane wperenenee NO. 19) 0 occcesecccccscs.. App. 119 Christensen, Robison, Robinson, Ploeger, Leavitt and Bodily, Antimicrobial Activity of Environmen- tal Surface Disinfectants in the Absence and Pres- ence of Bioburden, Journal of American Dental Association, Volume 119 (October 1989) (Refer- RNS aise i giicues ceric cs cece, App. 125 Clinical Research Associates, SUMMARY CHART: Environmental Surface Disinfectants, (1999) (compiling results of CRA Newsletter, Volume 18, Issue 3 (November 1994); Volume 19, Issue 1 (January 1995); Volume 20, Issue 11 (November 1996), and Volume 23, Issue 4 (April 1999)) (Ref- MI RIN 6556 isco k's ah Fs ois ord co ccc, App. 159 iv TABLE OF CONTENTS - Continued Page Robison, Robinson, Ploeger and Christensen, Tuberculocidal Activity of Glutaraldehyde and Glu- taraldehyde/Phenol Disinfectants, Journal of Den- tal Research, Volume 69, p. 379, Abstract No. 2161 (March 1990) (Reference No. 16)....... App. 161 Clinical Research Associates, SUBJECT: Disinfec- tants, Instrument Immersion, CRA Newsletter Volume 15, Issue 5 (May 1991) (Reference No. Fk PT oe ie Re ES say Sona ae? App. 163 Kolstad, Robert A., Ph.D., How Well Does the Chem- iclave Sterilize Handpieces? Journal of American Dental Association, Volume 129 (July 1998) (CRelecsmen INO. 2B). ise Scenes Cee eR Sees ee eee App. 171 V TABLE OF AUTHORITIES STATUTES: Ae URS ER eae ck co eae 10 OTHER AUTHORITIES: Altman, Lawrence K, M.D., New York Times, Investigating a Medical Maze: Virus Transmission in Surgery — Hepatitis B was Apparently Spread by a Doctor, but How?, New York Times (March 22, 1994) (Reference No. 3)........... Pert 5 PReOe cep eee 5 Christensen, Robison, Robinson, Ploeger, Leavitt and Bodily, Antimicrobial Activity of Environmen- tal Surface Disinfectants in the Absence and Pres- ence of Bioburden, Journal of American Dental Association, Volume 119 (October 1989) (Refer- saties ntti ih cioc oO OE PE PORE AR fy SRLS Res ii, i3 Christensen, Robison, Robinson, Ploeger, and Leavitt, Efficiency of 42 Brands of FaceMasks and 2 Face Shields in Preventing Inhalation of Airborne Debris, General Dentistry (November-December soya) (rementence- Ne S) ris ee 7 Clinical Research Associates, SUBJECT: Disinfec- tants, Instrument Immersion, CRA Newsletter Volume 15, Issue 5 (May 1991) (Reference No. AF) F0LEs CEERRG TEU OTE TORT TE ee 14 Clinical Research Associates, SUBJECT: Gloves, Non-Sterile Latex, CRA Newsletter Volume 15, Issue 9 (September 1991) (Reference No. 8) ........ 9 Clinical Research Associates, SUBJECT: Gloves, Non-Sterile Operating, Update Review, CRA Newsletter, Volume 16, Issue 10 (October 1992) etic inns a He ds. eS ETE EPP OE a bee aa ) vi TABLE OF AUTHORITIES — Continued Page Clinical Research Associates, SUBJECT: Operating Gloves, Important New Trends, CRA Newsletter Volume 19, Issue 9 (September 1995) (Reference oo eae) MRR RE Uy age es CU pete, gre Syed Oem soo ae 9 Clinical Research Associates, SUBJECT: Operating Gloves, Update, CRA Newsletter Volume 13, Issue 1 (January 1989) (Reference No. 9)..........- Yy Clinical Research Associates, SUMMARY CHART: Environmental Surface Disinfectants, (1999) (compiling results of CRA Newsletter, Volume 18, Issue 3 (November 1994); Volume 19, Issue 1 (January 1995); Volume 20, Issue 11 (November 1996), and Volume 23, Issue 4 (April 1999)) (Ref- CERNE INNO. RO he 4's ads dbkedawated avedewowes bas 11, 13 Gwaltney and Hendley, Transmission of Experimen- tal Rhinovirus Infection by Contaminated Services, American Journal of Epidemiology (1982) (Ref- ORONOD TH BEN bs ooo oc ove weve ee ueewkerinsees 11, 12 Harpaz, Seidlein, Averhoff, Tormey, Sinha, Kot- sopoulou, Lambert, Robertson, Cherry and Shapiro, Transmission of Hepatitis B Virus to Mul- tiple Patients from a Surgeon Without Evidence of Inadequate Infection Control, The New England Journal of Medicine, Volume 334, Number 9 (February 29, 1996) (Reference No. 4).............. 5 Knox, Richard A., A Nurse Hopes Her Infection Will Spur Action, Boston Globe, (April 6, 1999) (Ref- OTERO EO: TG i 6 oink one Kiss hah eee eae va 3, 10 Kolstad, Robert A., Ph.D., How Well Does the Chem- iclave Sterilize Handpieces? Journal of American Dental Association, Volume 129 (july 1998) CReGIRII TWO: Ba ons sobs bs on bck seeeneae 15, 16 Re Me eT Re a Vii TABLE OF AUTHORITIES —- Continued Page Korniewicz, Laughon, Cyr, Lytle, and Larson, Leakage of Virus through Used Vinyl and Latex Examination Gloves, Journal of Clinical Micro- biology, pp. 787-788 (April 1990) (Reference No. PEP !© two case-control studies of patients with . ‘ 2 rer m aaah a al “lal i biceathe cia So sina oe sa LR SR a ce . sessile eh tet ake ae = NE Ie gs Se 5 eg ee ee a TA he oF oe aa ae t => * SA est 8S 2 SELLA PIER a RIS sa PPE ie ESS Ci ners ea: ’ : : ms Baits NSS a aa RNa App. 33 acute hepatitis B that found no @ssociation between dis- ease and surgical history!” (and unpublished data), and the relatively small number of reported outbreaks of HBV given the estimated pool of infected surgeons. Outbreaks provide information about specific mecha- nisms of transmission of HBV from surgeon to patient. Since the early 1970s, 29 such clusters have been reported worldwide,?>.1%24 including 9 involving thoracic sur- geons.*!%22-24 Data from these outbreaks indicate an increased risk of HBV transmission from HBeAg-positive surgeons and during particularly invasive pro- cedures.°71-25 Transmission during many of these out- breaks was presumed to be caused by deficiencies in infection-control measures. Although this outbreak involved a high attack rate, our investigation did not identify any breaches in infection-control practices, despite an extensive search for potential modes of trans- mission. Unreported or unrecalled percutaneous expo- sures by the surgeon or operating-room staff are unlikely to explain such a high rate of transmission. Although this is the first reported outbreak involving a thoracic surgeon in the United States, four such out- breaks have been reported in the United Kingdom during the past decade.5?4 We found no specific features charac- teristic of thoracic surgery that were associated with transmission. Surgical fields are generally well visualized during thoracic surgery, and blind needle palpation is not often practiced. Thoracic surgery is, however, inherently highly invasive and of long duration, and these features have been linked to percutaneous exposure,*?8 glove failure,2?3! and HBV transmission.2! Indeed, whether caused by the duration of surgery or by specific factors App. 34 such as the closure of sternotomy incisions, frequent glove punctures during thoracic surgery have been reported.*©253!.32 In this outbreak, there was no associa- tion of HBV infection with the duration of surgery or the use of blood products (a possible indication of the invasiveness of a procedure); two case patients, in fact, underwent brief procedures requiring no blood products (a thymectomy and an open-lung biopsy). We found no associations between HBV transmission and specific pro- cedures, with the exception of cardiac transplantation, although in relative terms these were not long or complex procedures. Perhaps the minimal infectious inoculum of HBV is lower for patients receiving immunosuppressive therapy. Some surgeons have suggested that closure of the median sternotomy incision is associated with injury, although data to support this assertion are inconclu- sive.4!32 In our study, the surgeon’s technique of apply- ing hemostatic material to the sternal incision without a sponge may have caused injuries that were not apparent. However, one case patient underwent an open-lung biopsy that did not involve a median sternotomy. This outbreak may have been related more closely to factors unique to the surgeon than to factors inherent in thoracic surgery: indeed, lung biopsy is a procedure with little resemblance to most other thoracic surgical pro- cedures. Although HBeAg-positive persons almost always have highly infectious disease, the surgeon had an especially high concentration of HBV DNA during the outbreak, which may have contributed to aq high risk of transmission. The surgeon's technical skills were appar- ently not a factor, since operating-room personnel did not App. 35 recall that he had frequent needle sticks. The hand irrita- tion experienced by the surgeon in previous years had resolved with the use of hypoallergenic latex gloves, and there was no evidence that the surgeon had dermatitis during the outbreak. Hypoallergenic gloves are subject to the same quality standards as standard surgical gloves. The surgeon had pain over his index fingers during prolonged suturing. Other surgeons have described simi- lar experiences to us; we are unaware of any studies addressing this phenomenon. While participating in a one-hour simulation of suture tying,*’ the surgeon acquired paper-cut-like lesions on his fingers, and HgsAg and HBV DNA were isolated from washings of his hands. Such lesions, combined with the failure of his gloves, may have allowed contamination of patients with HBV. Although gloves frequently have leaks during sur- gery,2728,31,34,35 they nonetheless appear to be fairly effec- tive barriers against certain infections, even when leaks are present.*© Although there is increasing evidence that double gloves can prevent exposure of surgeons to blood during surgery,*> there is no evidence regarding the effec- tiveness of double gloves in protecting patients from blood-borne infections. Furthermore, advisory groups and professional organizations have not generally recom- mended the use of double gloves by surgeons. Additional studies are needed to assess the validity and gener- alizability of the suture-tying simulation and to define the role of gloves in preventing the intraoperative trans- mission of HBV. This outbreak has had tragic consequences for the case patients, their families, and the surgeon, who has left surgical practice indefinitely. The entire episode could App. 36 have been prevented had the surgeon received the hepa- titis B vaccine. We are indebted to Laurene Mascola, M.D., M.P.H., Michael Lim, M.P.H., Maria Rosario Araneta, Ph.D., M.P.H., Heidi Sato, M.P.H., and Alison Itano, M.S., for their assistance during this investigation; to Carlton Youngblood for performing the serologic tests; to Paul Swenson, M.D., for performing HBsAg subtyping; to Alan Redeker, M.D., for providing serum specimens from HBV-infected persons for genotype analysis; to Susan Govindarajan, M.D., for dot blot hybridization analysis of specimens from the surgeon; to J. Shaw for editorial assistance; to Miriam Alter, Ph.D., M.P.H., David Bell, M.D., Mary Chamberland, M.D., M.P.H., Walter Bond, M.S., Martin Favero, Ph.D., and Karin Lindsay, M.D., for helpful suggestions; and to the thoracic surgeon described in this report, for his cooperation and substan- tial contributions. REFERENCES 1. Hospital statistics: the AHA profile of United States hospitals: 1994-95 edition. Sasa American Hospi- tal Association. 1994. 2. Recommendations for preventing transmission of human immunodeficiency virus and hepatitis B virus to patients during exposure-prone invasive procedures. MMWR Morb Mortal Wkly Rep 1991;40(RR-8):1-9. 3. Lettau LA, Smith JD, Williams D, et al. Transmission of hepatitis B with resultant restriction of surgical practice. JAMA 1986;255:934-7. 10. aa: 12. App. 37 Rimland D, Parkin WE, Miller GB Jr, Schrack WD. Hepatitis B outbreak traced to an oral surgeon. N Engl J Med 1977;296:953-8. Heptonstall J. Outbreaks of hepatitis B virus infec- tion associated with infected surgical staff. Commun Dis Rep CDR Rev 1991;1:R81-R85. Johnstone BL, MacDonald §S, Lee S. et al. Nosocomial hepatitis B associated with orthopedic surgery - Nova Scotia. Can Commun Dis Rep 1992;18:89-90. Swenson PD, Riess JT, Krueger LE. Determination of HBsAg subtypes in different high risk populations using monoclonal antibodies. J Virol Methods 1991;33:27-38. Robertson BH, Khanna B, Nainan OV, Margolis HS. Epidemiologic patterns of wild-type hepatitis A virus determined by genetic variation. J Infect Dis 1991;163:286-92. Program manual for the GCG package, version 7. Madison, Wis.: Genetics Computer Group, 1991. Shafritz DA, Lieberman HM, Isselbacher KJ, Wands JR. Monoclonal radioimmunoassay for hepatitis B surface antigen: demonstration of hepatitis B virus DNA or related sequences in serum and viral epitopes in immune complexes. Proc Natl Acad Sci U S A 1982;79:5675-9. Dean AG, Dean JA, Burton AH, Dicker RC. Epi Info, version 5: a word processing, database, and statistics program for epidemiology on microcomputers. Atlanta: Centers for Disease Control, 1990. Dodd RY, Holland PV, Ni LY, Smith HM, Greenwalt TJ. Hepatitis B antigen: regional variation in inci- dence and subtype ration in the American Red Cross donor population. Am J Epidemiol 1973;97:111-5. 13. 14. 15. 16. ae; 18. 19. 20. App. 38 Meyers JD, Stamm WE, Kerr MM, Counts GW. Lack of transmission of hepatitis B after surgical expo- sure. JAMA 1978;240:1725-7. LaBrecque DR, Muhs JM, Lutwick LI, Woolson RF, Hierholzer WR. The risk of hepatitis B transmission from health care workers to patients in a hospital setting — a prospective study. Hepatology 1986;6:205-8. Alter HJ, Chalmers TC, Freeman BM, et al. Health- care workers positive for hepatitis B surface antigen: are their contacts at risk? N Engl J Med 1975;292:454-7. Williams SV, Pattison CP, Berquist KR. Dental infec- tion with hepatitis B. JAMA 1975;232:1231-3. Alter MJ, Coleman PJ, Alexander WJ, et al. Impor- tance of heterosexual activity in the transmission of hepatitis B and non-A, non-B hepatitis. JAMA 1989;262:1201-5. Prendergrast TJ Jr, Teitelbaum S, Peck B. Transmis- sion of hepatitis B by a surgeon. West J Med 1991;154:353. Bell DM, Shapiro CN, Ciesielski CA, Chamberland ME. Preventing bloodborne pathogen transmission from health-care workers to patients: the CDC per- spective. Surg Clin North Am 1995;75:1189-203. Carl M. Blakey DL, Francis DP, Maynard JE. Inter- ruption of hepatitis B transmission by modification of a gynaecologist’s surgical technique. Lancet 1982;1:731-3. Welch J, Webster M, Tilzey AJ, Noah ND, Banatvala JE. Hepatitis B infections after gynaecological sur- gery. Lancet 1989;1:205-7. App. 39 22. Coutinho RA, Albrecht-van Lent P Stoutjesdijk L, et al. Hepatitis B from doctors. Lancet 1982;1:345-6. 23. Haerem JW, Siebke JC, Ulstrup J, Geiran O, Helle I. HBsAg transmission from a cardiac surgeon incubat- ing hepatitis B resulting in chronic antigenemia in four patients. Acta Med Scand 1981;210:389-92. 24. Prentice MB, Flower AJE, Morgan GM et al. Infection with hepatitis B virus after open heart surgery. BMJ 1992;304:761-4. 25. Hadler SC, Sorley DL, Acree KH, et al. An outbreak of hepatitis B in a dental practice. Ann Intern Med 1981;95:133-8. 26. Tokars JI, Bell DM, Culver DH, et al. Percutaneous injuries during surgical procedures. JAMA 1992;267:2899-904. 27. Gerberding JL, Littell C, Tarkington A, Brown A, Schecter WP. Risk of exposure of surgical personnel to patients’ blood during surgery at San Francisco General Hospital. N Engl J Med 1990;322:1788-93. 28. Popejoy SL, Fry DE. Blood contact and exposure in the operating room. Surg Gynecol Obstet 1991: 172:480-3. 29. Fell N, Hopper W, Williams J, Brennan L, Wilson C, Devlin HB. Surgical glove failure rate. Ann R Coll Surg Engl 1989;71:7-10. 30. Quebbeman EJ, Telford GL, Wadsworth K, Hubbard S, Goodman H, Gootlieb MS. Double gloving: pro- tecting surgeons from blood contamination in the operating room. Arch Surg 1992;127:213-7, 31. Wong PS, Young VK, Youhana A, Wright JE. Surgical glove punctures during cardiac operations. Ann Thorac Surg 1993;56:108-10. CC nw a 34. 35. 36. App. 40 Pate JW. Risks of blood exposure to the cardiac sur- gical team. Ann Thorac Surg 1990;50:248-50. Harpaz R, Van Seidlein L, Averhoff FM, et al. Trans- mission of hepatitis B virus from a thoracic surgeon to patients. Infect Control Hosp Epidemiol 1994;15:352. abstract. Hosie KB, Dunning JJ, Bailey JS, Firmin RK. Glove perforation during sternotomy closure. Lancet 1988;2:1500. Rose DA, Ramiro N, Perlman J, et al. Usage patterns and perforation rates for 6306 gloves from intra- operative procedures at San Francisco General Hos- pital. Infect Control Hosp Epidemiol 1994;15:349. abstract. Olsen RJ, Lynch P, Coyle MB, Cummings J, Bokete T, Stamm WE. Examination gloves as barriers to hand contamination in clinical practice. JAMA 1993; 270:350-3. App. 41 REFERENCE NO. 5 GENERAL DENTISTRY/NOVEMBER-DECEMBER 1991 Efficiency of 42 brands of face masks and 2 face shields in preventing inhalation of airborne debris Rella P. Christensen, PhD Richard A. Robison, PhD Daena F. Robinson, BS Brad J. Ploeger, BS Ronald W. Leavitt, PhD Use of face masks by dental clinicians has increased as a result of the AIDS epidemic.! In response to clini- cians’ concerns about infectious disease transmission, the American Dental Association (ADA) and Centers for Dis- ease Control (CDC) issued recommendations for use of preventive measures, including face masks, during dental treatment.?° The use of face masks is now required by the Occupational Safety and Health Administration (OSHA).*5 However, none of these agencies provided information on relative merits of different types of facial barriers, which might give one the impression that all facial barriers are equally effective. While this may be true for blockage of large particles and splatter, dentists also must protect themselves from aerosols that are gen- erated during dental procedures and remain airborne following patient treatment.©11 In clinical studies characterizing aerosols by particle size, Pollok et al. showed that about half of such particles were 3 um or smaller.* Aerosol particles of this size have been shown to be particularly critical. In studies of 26 nonsmokers, Chan et al. demonstrated that particles about 3um in size have maximum deposition in the alveoli.12 According to Day et al., this deep penetration App. 42 into the respiratory tract increases the infectivity of microorganisms.'? Hence, face masks for dental use should block particles down to at least 3 um in size. Studies of toxicological warfare have confirmed that airborne organisms can cause infections in man.'*!5 To determine whether tooth-cutting procedures could lead to aerosols containing oral pathogens in numbers suffi- cient to infect humans, Belting et al. cut cavity prepara- tions on tuberculosis patients with positive sputum and cultured air samples following treatment.* They showed conclusively that oral tuberculosis organisms become air- borne in numbers sufficient to infect clinicians. At pre- sent, the use of high-filtration facial barriers with close peripheral fit is the best known way to minimize inhala- tion and infections from this type of airborne bacteria. Clinicians need to know the differences among the various brands of facial barriers on the market. This study compares the efficacy of various face masks and shields in blocking airborne debris. Materials and methods The test protocol specified four evaluations: (1) Three samples of all face masks studied were tested in vitro. (2) Selected face masks worn by clinicians were tested to determine clinical effectiveness. (3) Selected face masks were worn in high humidity, then tested to determine the high humidity’s effect. App. 43 (4) Finally, a dye tracer test was performed on selected face masks and shields to determine importance of peripheral fit. Collection of masks and shields Brand names of face masks sold to dental clinicians were identified, and identical masks sold under different brand names were eliminated. However, when confidentiality agreements prohibited identification of manufacturers, similar masks were tested, as clinicians at times have no way to confirm manufacturers and often must identify face masks by brand name only. Face shields were selected on the basis of market popularity and amount of facial coverage. The table lists brand names of 42 face masks and 2 face shields evaluated. Bacterial filtration efficiency testing Evaluation of 42 brands of face masks - Three unused sam- ples of each of 42 brands of face masks were coded and sent for bacterial filtration efficiency (BFE) testing at a commercial laboratory that routinely performs this stan- dardized procedure developed by Nicholes (Fig.1).16 A 24-hour culture of Staphylococcus aureus clinical isolate, strain Utah 15, at a concentration of approximately 104 colony forming units (cfu) per milliliter, was used in the following manner: (1) The culture suspension was nebulized (Chi- cago nebulizer*) to create a cloud with a mean particle size of 3.0 um. (2) The cloud was drawn through the test mask at a rate of 1 ft3/min. and onto a 6-stage App. 44 sampler (Andersen samplert) where particles were separated by size onto one of 6 Petri plates containing soybean casein digest agar (Fig. 2a and 2b). (3) The plates were incubated at 37°C for 48 hours; colony forming units were counted and probable hit values were computed according to Andersen’s method.!” To determine the consistency of delivery for the chal- lenge aerosol, control values were established through sampling without a filter. Acceptable limits for this aero- sol density were between 1,700 and 2,700 cfu/ft.3 To determine proper functioning of the test system, a refer- ence filter with a known BFE was tested. Challenge aero- sol sampling and reference material evaluation were conducted for every 8 to 10 test samples. The following formula was used to calculate filtra- tion efficiency of all test masks: Percent BFE = C - F x 100, Cc where C (control) represents the number of particles sam- pled when no mask was used an F (filtered) represents the number of bacterial particles that passed through the test mask. Mean BFE percentages were computed for each set of three identical masks. One-way analysis of variance (AOV) and the Bonferroni multiple comparison pro- cedure were used to determine differences in filtration efficiency among brands of masks. Evaluation of four face masks after clinical use — The Aseptex mask,* Dental Surgical mask*, and Magic Arch* App. 45 masks were tested. Two general dentists and their pri- mary chairside assistant wore coded face masks during patient treatment for one, two, three, and seven hours. Test periods were assigned randomly and repeated about eight times. No attempt was made to alter patient treat- ment. After each test, the mask was removed without contacting its surface, and BFE testing was performed. Mean BFE percentages were computed for each interval. One-way AOV and the Bonferroni multiple comparison procedure (alpha = 0.05) were performed to determine differences among intervals during which masks were worn, and between brands of masks tested and persons wearing the masks. Performance of 6 face masks in humidity > 90 percent - ADDS-Air-Flow laboratory mask,** ADDS-Vanced labo- ratory mask**, Aseptex mask, Aseptex Plus mask, Duck- bill surgical mask,+ and the Dental surgical mask* were tested. Two subjects (a woman 54 kg and a man 100 kg) wore each of the test masks for 30 minutes in a chamber (42 inches x 24 inches x 24 inches). Their heads and shoulders were positioned inside the chamber, 6 and 12 inches, respectively, from an air-slurry polisher (Prophy Jet 304) operated on medium water and powder settings with an air pressure of 80 psi. After 30 minutes, the masks were removed without contacting their surfaces and BFE testing was performed as described above. BFE percentages were computed and plotted against mask type. Dye tracer testing - The Aseptex mask, Magic Arch mask, Cover shield,** and Op-d-Op shield*** were tested. A test also was performed using the Aseptex mask in combination with the Op-d-op shield. App. 46 A subject’s head and shoulders were positioned inside a chamber (30 inches x 30 inches x 36 inches) with a nebulizer (Micro Mist Aerosolizer #P220*'t') emitting a dye (Blue Crayola Tempera##+) diluted with three parts Crayola Temperat#+ deionized water. Mean particle size of the airborne dye was 4.8 um. The distance between the facial barrier and orifice of the nebulizer was 6 inches (Fig. 3). Figures 4a to 4i illustrate the steps in the test pro- cedures. A 2 inch x 2 inch cotton-filled gauze sponge (Healthco No. HCOC535051"") opened at its center was positioned so the nose was covered (Fig. 4g). Imperme- able plastic was placed such that, for each facial barrier tested, inhaled air was allowed to enter: (1) through the mask and peripheral border (Fig. 4c); (2) through the mask material only (Fig. 4g); and (3) through the peripheral border only (Fig. 4h). Figure 4i shows the results of a positive control test in which no facial barrier was worn. All tests were conducted for 10 minutes. The gauze nose wraps from all but the combination Aseptex Mask/Op-d-op Shield tested were ranked according to area and intensity of dye stain by 21 evalua- tors who were not associated with the study. Kendall's coefficient of concordance was computed to determine agreement between evaluators. passat: > Fee ee App. 47 Results Bacterial filtration efficiency testing ~ In Figure 5, the 42 face masks tested are ranked in order of highest to lowest mean BFE scores. Lines connecting brand names indicate statistically non-significant scores, and overlap- ping lines indicate statistically similar groups. The test masks separated into two non-overlapping significance groups. The high filtration group included 22 face masks with mean BFE scores of 74 to 98 percent. All but two masks in this group were soft, pleated, rectangular masks. Two rigid, preformed, cup-style masks with a unique design (the ADDS-Air Flow laboratory and ADDS-Vanced laboratory masks) had filtration values of 91 to 92 percent. The scores of the 20 remaining masks were significantly lower (13 to 51 percent). In fact, all brands of conventional, cup-style face masks, including the Aseptex and Aseptex Plus brands, were in the low filtration group. Figure 6 shows mean BFE percentages for 4 face masks worn during clinical treatment. The two soft, pleated, rectangular masks (Dental Surgical and Magic Arch) had efficiency scores of 97 to 99 percent, regardless of length of time worn. The Aseptex Plus proved to be Statistically more efficient than the Aseptex. No statistical differences were observed with respect to persons wear- ing the mask. Figure 7 shows the mean BFE percentages for 6 face masks tested under normal (about 50 percent humidity) and humid conditions (> 90 percent humidity); compari- son of BFE percentages shows mask filtration was not App. 48 affected adversely by high humidity. The size and gender of the subject also had no effect on BFE scores. Dye tracer testing — Figure 8 shows the gauze sponges worn over the test subject’s nostrils during 10-minute dye tracer tests. Kendall's coefficient of concordance (0.993) showed high agreement between the 21 evaluators who ranked the sponges. In Figures 8a to 8i, the gauze sponges are shown as ranked, from least to most effec- tive, by the evaluators. Results indicate the following: (1) All test barriers blocked some airborne dye and proved more effective than no barrier (com- pare control gauze in Fig. 8a with all others). (2) The face shields were least effective in blocking airborne dye (compare Fig. 8b and 8c with all others). (3) The high-filtration mask provided the best defense against penetration (compare Fig. 8g, 8h, and 8i with all others). (4) High-filtration material and close periph- eral fit were needed for optimum blockage of aerosols (compare Fig. 8i with all others). Figures 9a and 9b show leakage of dye tracer onto the interior surface of a high-filtration mask after 10 and 30 minutes of use. This problem was evident to varying degrees in all test masks. The colored dye enabled us to observe a problem not clinically apparent, because most dental aerosols (such as saliva and water) are colorless. Mask penetration is highly significant because it can bring airborne organisms into contact with the wearer’s lips, nostrils, and skin. Oh Bias inc nt ects cited Nee IP tee ey ay ae g App. 49 In an additional test in which the Aseptex mask was used in combination with an Op-d-op Shield, aerosol penetration was diminished only slightly (Fig. 10). The combination did not provide the level of protection offered by the high-filtration face mask (Fig. 8g to 8i). Discussion Several theories concerning face masks were dis- proven in this series of tests. For example, filtration effi- ciency was not decreased by use in a humid environment for up to 30 minutes or by clinical use up to 7 continuous hours. Filtration efficiency was not affected by gender or size of the clinician. In addition, this study showed clearly that the test masks were not equally effective in preventing penetration of airborne debris. Shields proved to be substantially inferior to masks, owing to their lack of peripheral fit, which was shown to be as important as filtration efficiency in blocking airborne debris. Size of airborne particles is important regarding the effectiveness of face masks. Investigators have demon- strated that dental procedures generate large quantities of aerosols 3 um and smaller.* Such particles remain sus- pended at the end of treatment,®7 and can penetrate to the alveoli of the lower respiratory tract,!2 where their infectivity is greatly increased.!3 Therefore, dentists and staff should use facial barriers that block particles of this size, but our results showed only about half the test masks met this criterion. Conventional, preformed, cup- style face masks had low filtration. When choosing masks, dentists must consider the fact that 50 percent or more of deleterious airborne particles can filter through App. 50 this type of mask. After reviewing these data, two face mask manufacturers redesigned their preformed, cup- style face masks to achieve high BFE ratings (Triple Layer by 3M and Surgical Comfort by Healthco). These masks are now available. It is clinically relevant to establish the length of time a face mask can be worn. This investigation showed neither high humidity nor use over time affected signifi- cantly the filtration of the masks tested. Dye tracer tests indicated the critical factor is soak-through of airborne debris. This process, called wicking, poses a threat when the wearer’s lips and nostrils come in contact with moist areas, thus establishing direct mucous membrane contact with organism-laden material. Current mask design does not allow clinicians to determine when wicking has occurred, because interior surfaces of masks are not stained visibly when wet by colorless fluids. Given pre- sent mask technology, we agree with Craig et al., who suggested mask changes after 20 minutes in aerosol and 60 minutes in nonaerosol environments.'® These recom- mendations were based on culturing of masks worn clini- cally. When worn longer than the recommended times, the masks became impregnated with microorganisms and, thus, were a source of, rather than a barrier to, potential pathogens. When gathering information on filtration efficiency of face masks, dentists need to know that efficiency rat- ings can be generated by two tests. One is the BFE pro- cedure performed here; the procedure is well suited to dental use of face masks. The other is the Greene and Vesley test,!? which measures filtration from the inside of the mask outward through use of large particles. This test App. 51 is relevant to surgeons whose primary concern is deposi- tion of droplets from the operator onto the patient. Unfor- tunately, Greene and Vesley test percentages often are used to promote masks to dental personnel because such ratings are substantially higher due to use of larger-sized test particles. Filtration efficiency ratings of preformed cup-style masks increased slightly after three hours of clinical use. This phenomenon is common in BFE testing of cup-style masks, and is thought to be caused by impingement of droplets onto the mask. Some pores are blocked, which temporarily increases filtration efficiency. Droplets then coalesce, reducing filtration efficiency. Confidentiality agreements between manufacturers and distributors often result in very nearly the same product being sold in different packaging. In this study, testing of some similar masks was performed because, in some cases, positive identification of manufacturers could not be obtained. Testing was justified on the premise that data was needed for specific brand names for which manufacturers could not be identified positively. How- ever, test results indicate similarity of manufacturing technology, rather than the manufacturer, was the key factor in mask filtration efficiency. Test masks were sepa- rated by BFE ratings into two distinct groups, although masks from more than two manufacturers were evalu- ated. With only a few expectations, the 42 masks were divided into a soft, pleated, rectangular, high-filtration group; and a rigid, preformed, cup-style, low-filtration group. App. 52 Conclusions Bacterial filtration efficiency ratings here indicate 22 of the 42 brands of test masks ensure efficient blockage of airborne debris. Protective barriers against small-particle aerosols should be selected from among this group (Fig. 5). Preformed, cup-style face mask with a conventionai design, and face shields all provided significantly less blockage of airborne particles. The main factor in deciding when to discard a face mask of nay kind was degree of wicking. Because pene- tration of fluids such as water and saliva cannot be observed on the mask’s interior surface, the recommen- dations of Craig et al. (to change masks after 20 minutes in aerosol and 60 minutes in nonaerosol environments) should be followed.'§ They showed that masks worn for longer periods became a source of infectious material.8 Dr. Christensen is director, Clinical Research Associates, Provo, Utah, where Dr. Robison is coordinator; Ms. Robinson is microbiologist; and Mr. Ploeger is virologist, Microbiology Section. Dr. Leavitt is an associate professor of microbiology, Brigham Young University, Provo, Utah. Address correspondence to: Dr. Rella P. Christensen, Clin- ical Research Associates, 3707 North Canyon Road, Suite 6, Provo, UT 84604. Acknowledgments The authors thank Nelson Laboratories, Salt Lake City, for performing bacterial filtration efficiency tests; Dr. H. Gill Hilton and Dr. Howard B. Christensen, Center for Statistical App. 53 Research, Brigham Young University, for statistical consulta- tion; and Mrs. Judy Davis for manuscript preparation. “Dependable Scientific Glass Co., Salt Lake City, UT 84115. tAndersen 2000 Inc., Peachtree City, GA 30269. 43M Co., Dental Products Division, St. Paul, MN 55144. #Alpha Pro Tech, Inc., North Salt Lake City, UT 84054 ““American Diversified Dental Systems, Anaheim, CA 92806. ttBaxter, Deerfield, IL 60015. ¢{Dentsply, York, PA 17405. ##GRD Products, Grand Junction, CO 81501. ““Op-d-Op Inc., Roseville, CA 95678. tttMicro Mist Corp., Hudson, OH 44236. ¢t¢£Binney and Smith Inc., Easton, PA 18044. ###Healthco Inc., Boston, MA 02116. References 1. Verrusio, A.C., et al. The dentist and infectious dis- eases: A national survey of attitudes and behavior JADA 118:553-562, 1989. 2. Council on Dental Materials, Instruments, and Equipment; council on Dental Practice; Council on Dental Therapeutics (of the American Dental Association). Infection control recommendations for the dental office and the dental laboratory. JADA 116:241-248, 1988. 3. Centers for Disease Control. Recommended infection- control practices for dentistry. MMWR 35:237-242, 1986. App. 54 4. Joint Advisory Notice: Protection against occupa- tional exposure to hepatitis B virus (HBV) and human immu- nodeficiency virus (HIV). Fed Reg 52:41818-41824, 1987. 5. Occupational Safety and Health Administration. Occupational exposure to bloodborne pathogens; Proposed rule and notice of hearing. Fed Reg 54:23042-23139, May 30, 1989. 6. Pollok, N.L. III; Shay, D.E.; and Williams, G.H. III. Evaluation of airborne contamination in a dental school clinic. J Baltimore Coll Dent Surg 27:4-20, 1972. 7. Larato, D.C., et al. Effect of a dental air turbine drill on the bacterial counts in air. | Prosthet Dent 16:758-765, 1966. 8. Belting, C.M.; Haberfelde, G.C.; and Juhl, L.K. Spread of organisms from dental air rotr. JADA 68:34-37, 1964. 9. Travaglini, E.A.; Larato, D.C.; and Martin, A. Dis- semination of organism-bearing droplets by high-speed dental drills. J] Prosthet Dent 16:132-139, 1966. 10. Micik, R.E., et al. Studies on dental aerobiology: I. Bacterial aerosols generated during dental procedures. ] Dent Res 48:49-55, 1969. 11. Holbrook, W.P., et al. Bacteriological investigation of the aerosol from ultrasonic scalers. Br Dent J] 144:245-247, 1978. 12. Chan, T.L., and Lippmann, M. Experimental mea- surements and emptrical modelling of the regional deposition of inhaled particles in humans. Am Ind Hyg Assoc ] 41:379-409, 1980. 13. Day, W.C., and Berendt, R.F. Experimental tularemia in Macaca mulatta: Relationship of aerosol particle App. 55 size to the infectivity of airborne Pasteurella tularensis. Infect Immun 5:77-82, 1972. 14. Morton, J.D. Ability of present sampling devices to determine the particle size distribution of biological aerosols sufficiently accurate to predict the dose response in experimen- tal animals. Eleventh Tripartite Conference on Toxicological Warfare. Frederick, Maryland, Army Chemical Center, October 28, 1956. 15. Compton, J.A.F. Military Chemical and Biological Agents: Chemical and Toxicological Properties. Caldwell, New Jersey, The Telford Press, 1987, pp. 354-407. 16. Nicholes, P.S. Comparative evaluation of a new sur- gical mask medium. Surg Gynecol Obstet 118:579-583, 1964. 17. Anderson, A.A. New sampler for the collection, siz- ing, and enumeration of viable airborne particles. J] Bacteriol 76:471-484, 1958. 18. Craig, D.C., and Quale, A.A. The efficacy of face- masks. Br Dent ] 158:87-90, 1985. 19. Greene, V.W., and Vesley, D. Method for evaluating effectiveness of surgical masks. ] Bacteriol 83:663-667, 1962. JOSIA peay onseid 0) poyoeye onsejd ‘pidu “meajp SINOJUOS [eIDe] puv surey Sasse]3 onseyd yy 0} poprour ‘onseyd ‘pidu ‘1eay> $2 p ‘ojsue}901 poyeayd Syos San p ‘o[Bue}D01 payeayd Syos S31} p ‘o[sue}s01 payeayd “yos Sal} p ‘a[sue}I01 payeatd ‘yo dens onseys | ‘dno pouuojaid ‘prany sdoo] e9 onseje Z ‘o[3ue}901 payeayd ‘yos sdoo] 12 onseye Z ‘a]SuB}9a1 payeajd ‘yos S23) p ‘a[suR}901 poyeayd yor Son p ‘poyseyje JuusA09 aA onseld seajo TM a[Buejo01 poyeayd “yo sdooj Je oNseyle Z ‘o[3ue}0I poyeajd ‘yor sdooj Je9 oNseI> 7 ‘a]BuejD01 poyeayd ‘yo dens oyseje | ‘dno pouuojaid ‘pr3ny dens onseje | ‘dno pouuojaid ‘prary sdoo] Jed se at0s Sa[OY JayoureIp yout ¢'Z “dis ureoy onse]g sdooj Jed oNse]> Z ‘a]Sue}o0I poyeajd ‘yor SON p “ofduejo01 poyeayd 4yos dens onseye | ‘dno pouuojaid ‘pi3ry dens onseje | ‘dno pouuoyjaid ‘pidny dens onseje | ‘dno pouuojaid ‘pi8ny dens onseje | ‘a[8uejoor poyeayd “yoo Ssdoo] Jed INseIP 7 ‘aj3ue}D01 poyeatd ‘yo S31} p ‘ajduejoo1 poyeayd “yos SN} p ‘a[duej}Oa1 poyeayd “yoo sdoo] Jeo onseye 7 ‘o]Suejoo1 payeayd ‘yo dens onse[s | ‘a[8uejs01 payeajd ‘yo asou JOA0 dens onseje | ‘Wosut dno pouuiojaid ‘pry dens onseye | ‘dno pouuojasd ‘piary Son p “opdueyos []Iqyonp ‘Yyos dens onseje | ‘dno pouuojaid ‘pidny dens onseja | ‘9[8uejs01 payeayd “yo sdoo] Jeo onseye Z ‘a]Bue}901 payeayd ‘yo dens onseyo | ‘o[3uej901 payeayd “yoo Peal} ONse[e | ‘a[sue}01 poyeayd “yos dens onseje | ‘dno pouuojaid ‘prany dens onseye | ‘dno pouuoyaid ‘pi3ry SON p ‘a]Fuee1 payeatd “yos dens onseye | ‘dno pouuojaid ‘pr8ry dens onseje | ‘dno pouuojaid ‘piary dens onseje | ‘dno pouojaid ‘pidry sdens onseje 7 ‘dno pouuiojaid ‘prary sdeqs onseye 7 ‘dno pouuojaid ‘pr8ny dens onsejs | “dno pouuosaid ‘pi8ny App. 56 uondidseg oouneaH{ Uead] “Y UH 4J9{XB Gy We uosuyor wz UosuYyos uosuyor UOsUYos oouneoH oounfeaH{ SUIaISAG Ajayesorg ueUeog 3 WOoIpUy Toe 1em09 aournTy aourllTy [POD [ewac] jay [eyuoq jay UB JUNOosI(] [euotssajoi1g UB iuNoosic] [euorssajoig UIaY9g [eyuoc] jsy Teiwaq eydiy Jayxeg Jayxeg Jayxeg oouneay jeiwaq eydry jonorg SUIsISAg Ajayesorg Jayxeg jonorg feuag eydiy oouNeaH{ yseul ews eydry UONII}01g IOLUE Ajog purjs] Jayxeg Jayxeg We We S\sTusY UBIINS SUIDISAG [BIUAC] POYlssaic] UBOUOUTY SUIDISAS [BIUSC] PoYtsJaAIG] uRSUSUTY [Pajop Auedwio,y f \ pyerys do-p-dg 7 PJetys JoaoD | (spjays 290.1) eu-ni) “Zp SISl# Ysew eoidms uo-aty [Pp yseul Zoynue J] suiding “op yseul [J ouldmg “6¢ yseul feoidmg “g¢ yseul Zoyyue peorsmg “1 ¢ yseu dooj-me ‘Yyos ‘o¢ YSBUI JOUSISOp BUIBIG “C¢ YSU! VUUIPPaYS “pe yseut dooj-iwa payeajd-pjaryg “¢¢ YSU BY PJOTYS-ooj}01g “ZF YSEUI PJPTYS-901g “[¢ pend pmy yim yseur dno pouuojoig ‘o¢ ySeul Ie YAJOY “67 Sdooj 189 YIM Ysvus yy WLIO] poywo[q “gz SVU PIyB3[q “LZ YSBUI [BOIS INS Popjoyy “97 YSeul JejNda1 popjoyy “SZ JSCUI PIploW “¥Z Yseul yore dIBePy “¢7 yseul UOHLIOSI UOHeNIY-Ysty] “ZZ YsBul [BOIS IMs 20-304 °[Z seul feoisms pjorys pmjy “Oz yseul feoisms pend pny y “6 | YSBUI JOM YOo]D0v. “g] Hasut ajqesodsip tyim surey Yseus s0e4 | yseul Joyesidsas w? isnq] 9] yseul peors.ms [piqyong *¢| yseus anjq aqesodsiq] *p| ySeU [BOIS [RUA] “¢| yseul sinpsooid jeywaq “Z| yseul ampooosd peyuaq] “| | yseur dag-q 0] SPU [BOIPSU MOWUOD 6 YSBUI [BOIZINS SIss¥{> su0> SPU [BOIS S1sse] > yseul sniq xaidasy ysew xaidosy ySeUl Ht {-WOD [py-idasy yseus AloyeJoge] poour A -Sqqy seul AioyeJoge] MOL] INY-SGdV seul sjorued Itx0] -UON NOSE “| (sysmu 220.4) aweu pueig NANmrnwor oo SPpatys ad" 2 PUL SHSBUI 99Ej Zp JO QUIeU puBAQ Aq IsY [eINAqGeYdTy “| afquy ieee App. 57 REFERENCE NO. 6 VOLUME 19, ISSUE 9 - SEPTEMBER 1995 CRA Newsletter SUBJECT: OPERATING GLOVES, IMPORTANT NEW TRENDS Never before have so many dental clinicians used oper- ating gloves routinely. Extensive use has revealed sensi- tivities not anticipated. Glove manufacturers are now seeking alternatives because glove sensitivity can force clinicians to cease practice. This report on new powder free alternatives focuses on: (1) Quality, clinical charac- teristics, & cost of 32 brands of powder free gloves; & (2) Clinical & lab data that strongly implicate glove defects in virus transfer. METHODS: A. GLOVE ACQUISITION - 6 boxes of about 100 gloves each from 32 powder free glove brands were acquired from 20 sources in 12 U.S. states from January through March ‘95. B. CLINICAL CHARACTERISTICS TEST — 300 each of the 32 glove brands (9600 total) were used during routine clinical treatment by dentists & auxiliaries at 29 clinical sites in 19 U.S. states & rated according to: (1) Fit, (2) Tactile sensitivity, (3) Taste, (4) Tacki- ness when wet, (5) Resistance to tearing, & (6) Cuff length (adequate to pull over long sleeve). C. MANUFACTURING DEFECTS TESTS - About 290 each of the 32 glove brands (9280 total) were tested in-vitro for perforations (FDA Water Leak Test) & 9 of each brand (288 total) were tested for time before hydration occurred (Dental-Alert Monitor by Novatec [713] 266-1976). App. 58 LSAG=L ‘L-1 Jo 2J"Is UG , uopurpAy ayerpoumuy smopye a snosod sy Aur, b “saaoys FAUTA - $}22JIP JCUPULLS|p JOU SIOP 489] YB] 19984, VA § Bra | ot aay Saas CEICSFITEST Say TIpMOy AMA Pussy 36 tt b unr : UIX-TWCS)E@e Paty Tapmog uy, ajeseing | 46 ve b ug = UIX-T WS) ddAWd 2944 J9pmog FAUTA Id | 79 SP aa Z sor CEASYSZMD 93iy Dpmog sisipieg | FL 6? apt ZT %sor - ei P 76 rr air Z Tis UIX-TICS SX tOSd aay Jopmog sayy Wiexy 76 oF ipl G TPs UTWS-SXY 10C-91 Saag Jopmog ALioquel) 78 SF apa ¢ %tP VIX’ TW-S-SX)-80tdd 9949 Jopmog esply | 8 Ts une Z Ye TT W-S-SX0# Spi OU) aij Japmog qeeg | 36 SF ut 77 TRS UPWCS) Lidst Saiy epaog painjxs |, ait SF ~ eae 7T Ys TW-S-SXP 112-91 334g Topmog x9} 7d 7Ti SP “Gilt ¢T At VIX" TWS)t0-0te- Ol “ad Srey | 79 SF “aa TT %Lo UIX-TA-S-SX)-000c 90 Japmog suiyg | 36 SF “apa OZ Ye CTA-S)07T 9329 Topmog preny ar] 701 ts Up GT Yr C(TA-S-SX)-ddd 3805 PD Wei -O1g | Era’ oF “apa TZ %Lt Ta SP aa SZ re UIX-TW-S-SX)-tds Sa HEE 701 6F Wal OF Wis UTW-S)0007 Saay Tapmog seqpayy | aii oF afar FZ Yet UT W-S-SX)-OF7 Fay Fpmol HM SS For tY aya SZ Toe UTW-S)OS¢-70) Said 931] Tapmog won | 46 oF “Ul OZ aa | TTWCSHF Bpid 00) sary Tapmog suydyy | IL rr “ahr OF RP TICS) 8la8 Were eommULEyY 701 OF “ERT OF RIF CTA-S)00T 998g Sopmog Wiexg Pesipsyy rae] | 39 Ts apa OF TP UTW-S-SXF pid 00) “pps feo Fit oF “Wf 97 ad UTWS-SXS6-0F P21] Japmog Gono peng) | 76 sF Witt ZZ wri ; T 36 ws “aya ZZ wr UP W-S)E10t-D “GH plotting xapoisyy | 7a TF “UT OF se CIWS OPTS72O OI UPL) HL Uepeyy | 8 Ts ia OF ard UPW-SHGF pid 00) SA0fF) Wapjposy | Fit oF ap OE Yt CTVCS) $11 Wiiojue> Tpsry 701 LY apa EZ Ror (TAS) O TIL) Spepmog rajssor ) | INO) 729 flit BZ FLO TIOULOD) (6 C/1s)001 G-Paorg | oe im ~ SAL oy cs SHAOTD AqaA AAAGMOd 7 AO LSOD ¥ ‘SOLLSRIALOVUVHD TVOINITD ‘(2mn uoNnespdAy 2 $393j2P) ALVYTWAO AAOTID ‘I App. 59 BEST GLOVES OVERALL ARE Biogel-D, Crosstex Powderless, Ansell Conform, Golden Glove & Aladan Tri-Clean 110. LEAST EXPENSIVE, BEST OVERALL GLOVE is Golden Glove. 2. CLINICAL & LAB DATA THAT STRONGLY IMPLI- CATE GLOVE DEFECTS IN VIRUS TRANSFER. PREMISE: Gloves are worn by clinicians to prevent expo- sure of patient & clinician to each other. Integrity of the barrier is first concern. IN VIVO LEAKS DEMONSTRATED: A Los Angeles surgeon who infected 18 of 142 patients (13%) in 10 months with hepatitis B theorized that finger irritation & pressure from suture tying might be implicated in virus transmission. Tests showed hepatitis B virus in washings from inside of gloves he wore while tying sutures, indicating he shed virus through skin on his fingertips. These viruses (42 nm), shed through irritated skin & escaping through defects in glove fingers provide first plausible explanation of disease transfer between patients & a clini- cian practicing Universal Precautions. (New York Times, March 22, 1994, C3) IN VITRO LEAKS DEMONSTRATED: Investiga- tors testing 240 latex & 240 vinyl exam gloves found leakage of test virus $X174 in both types of gloves, regardless of whether gloves were just removed from box or stressed in 3 levels of simulated use. At heaviest use level, vinyl gloves leaked virus 9 times more frequently than latex gloves tested. (Korniewicz, D.M. et al., J Clin Micro 1990; 28:787-788) **WITHOUT EFFICACIOUS INFECTION CONTROL PRODUCTS, THERE IS NO CON- TROL OF INFECTIOUS DISEASES. App. 60 CAUTIONS: A. Chlorination treatment is most common ES way to make powder free gloves. Pro- cess is conceptually good because it lowers protein antigens. In practice it is often done poorly to save time & money, & results in shortened shelf life, increased defects, slippery surface, foul taste & smell on gloves, brittle & crack- ing fingernails on clinician. B. Vinyl is porous. **CHOOSE POWDER FREE GLOVES CARE- FULLY. STORE COOL, & USE WITHIN 3-4 MONTHS. 3. CRA CONCLUSIONS: Dental clinicians need to be aware that routine use of operating gloves can result in various hypersensitivity symptoms. Prevention is superior to searching for solu- tions after symptoms develop. New option is powder free gloves. Outstanding gloves in evaluation are listed above under BEST GLOVES. App. 61 REFERENCE NO. 7 VOLUME 16, ISSUE 10 - OCTOBER 1992 CRA Newsletter SUBJECT: GLOVES, NON-STERILE OPERATING - UPDATE REVIEW One year ago, CRA reported on quality & cost of 6,000 non-sterile operating gloves representing 20 brands used by dental clinicians (see Sep. ‘91 CRA Newsletter). Only 4 of 20 brands tested had combination of reasonable cost, overall good clinical characteristics, & low defects (7 of 20 brands met FDA’s specification of 4.0% or less defects). Since both clinicians & patients depend on operating glove quality as primary infection control barrier, 1 year later the same tests were performed on all gloves still available to check for improvements. Following report is written in style similar to ‘91 report to facilitate compari- sons. 1. TEST METHODS. (a) GLOVE PURCHASE - Three boxes contain- ing 100 gloves each of 24 brands of operat- ing gloves were purchased from 36 distributors in 12 states in April, May, June ‘92. These included brands from the ‘91 evaluation, several new brands, & gloves from 1 manufacturer sold by 3 different distributors. (b) CLINICAL CHARACTERISTICS TESTING - Seven characteristics evaluated were: (1) taste, (2) powder amount & texture, (3) tackiness after wetting, (4) tactile sensi- tivity, (5) resistance to tearing, (6) fit, & (7) cuff length & width. (c) App. 62 MANUFACTURING DEFECTS TESTING - FDA in vitro Water Tight Test was per- formed on 7,006 gloves to identify manu- facturing defects. (All 7,200 gloves expected in this test were not available for testing due to presence of less than 100 gloves in 24 of the 72 boxes. One box con- tained only 54 of expected 100 gloves!) 2. RESULTS. Refer to chart on page 2 for brand names that correspond to number abbreviations below & for details of evaluation. (a) Gloves with best combination of reason- able cost, good clinical characteristics, & low manufacturing defects (pinholes) were defined as having cost of 8 cents or less, overall “good” clinical rating, & 4% or less defects. By these criteria #’s 1, 2, 3, 4, 5, 6, 7, 8, 10, 11, 13, & 17 were noteworthy. Gloves with best combination of above characteristics both in ‘92 & ‘91 were #’s 1 & 3. Gloves with least manufacturing defects (pinholes) were #’s 1, 4, 9, & 12. Gloves with least cost (6 cents/glove) were *s 1, 2, 3, 5, 35, ate Oe oe Comparing ‘92 to ‘91 evaluation, following was observed: (1) Significantly fewer manufacturing defects were observed (i.e. 2.5% or 176 total defective gloves out of 7,006 tested in ‘92 vs. 6.6% or 392 total defec- tive gloves out of 5,937 tested in ‘91). App. 63 (2) Clinicians desiring gloves with 4.0% or less manufacturing defects (FDA maxi- mum allowable) have more brands from which to choose in ‘92 (i.e. 19 in "oe Va. A 94). (3) Clinicians desiring gloves with overall best combination of reasonable cost, good clinical characteristics, & least manufacturing defects have more brands from which to choose in ‘92 (i.e. 12 in ‘92 vs. 4 in ‘91). (4) No gloves were rated excellent in all clinical characteristics in ‘92 (i.e. 0 in ‘92 vs. 2 in ‘91). 3. OBSERVATIONS: (a) More boxes of gloves lacked the expected 100 gloves than noted in previous tests (24 of 72 boxes). Most problematic were glove #’s 1, 10, 12, & 15. Cuffs on about half of gloves tested were too short to remain over fitted uniform sleeve to provide continuous barrier from hand onto arm. Some glove designs have recognized need for anatomically placed thumb on non-ster- ile gloves to relieve pressure on hand (glove #’s 17 & 21). Glove 23 was nitrile rubber rather than latex, which conforms to hand better & relieves pressure. Many glove brands now make “hypo- allergenic” claim. CRA questions whether any glove made from latex can be truly hypoallergenic. In future, FDA may set App. 64 standards for gloves making this claim, but currently no standards exist. (e) Since manufacturing defects continue to be a consideration, methods are needed for clinicians to test gloves before use &/or apply something to gloved hands to seal surface. 4. CRA CONCLUSIONS: Overall quality of non-sterile operating gloves tested has improved substantially over last year. Twelve of 24 brands had combination of reasonable cost, good clini- cal characteristics, & lowest manufacturing defects — a 30% improvement over ‘91 test results. One glove (S.S. White Latex Dental Exam Gloves) had no manufacturing defects in 300 gloves tested, which demonstrates holes in gloves are not inevitable. CRA urges all glove manu- facturers to strive for consistent zero defects & improve clinical characteristics. 4 a - oS a Bir DS > mat Bd + oR & a x hs oe Powis en) ie 4 e App. 65 (aA0]8/P¢"L) LS88# S9X0q 07% jo oseB) S9A0]S) “PTZ pooy OOL/87'L$ XOB'] WBXF/JOO],J WeX9],J [RoseULIey “¢] (aa0j8/9¢"L) LIOLOLIDOOH F LOOLOLDOOH# S9X0Q OZ jo ose) SeA0CTH %0'I / wey OO1/0S'L$ UoneUTUeXY xXoqe] a[qesodsiq] Ooupeop] “Z| (2A0]8/99) PIW-LS-D'T# SOX0G ol jo ose7) S9A0]L) UOTPBUILBX %I'E poor OO1/S6'S$ Xaye’] oTuUadoyeodAPy yonoy AIS “[ | (2078/51) S9X0q ()] JO 9S¥D ZOOI# %L'| poon OOL/0S L$ S2AO[H [BOIPSY Xoje’] UBpeTY ‘O] (2a0]8/9g) SIX0G Qj JO 9seD L00S6# %0'0 ie J 001/00'8$ SOAO|F Wexy [BUI] Xe] NY S'S “6 (aa0]3/9¢°9) S9X0G ()| JO BSED ZIOI# “pT pooy OOL/SP'9$ S9AO[H UONBUTUIBXY XB] XOOAOTH_“g (2078/96 '9) S9X0q (| JO ase_ OSO8# %0'7Z poor 001/06'9$ SOAO|H) UOTBUIWIEXY X9yB'] sIBDJoqqny *Z (aa0j8/9¢°z) l# S3X0q Ol jo oases) S9A0]S) %E| poo OOL/0S ‘L$ Xj] s]qesodsiq] .NOA SeAo]H BIpNy,, “9 (20]8/99) S9X0Q YZ JO 9s¥D £0001 LOOOI# “PZ poor OOL/S6'S$ SdA0|H UoORBUTUIEXY o[qesodsiq] oulIg “¢ (2a0j8/9¢z) S9X0q (| JO aseD ZOI-X T# %0'| poo OOL/0S'L$ SdA0[H WexY poyyodsiq xoyumury = “p (anoj8/99) JO}OD [RNeN# S9X0g QZ JO asBD SSAO]H UORPUTUTEXT %'TZ poon 001/00'9$ X9]B'] 9[U2}¢-UON TPH] OdV “Lx (aA0]8/99) SIXOQ (| JO 9sBD IZ7LINV# %/"| poor OO1/S6'S$ S9AO[H Wexg Xaye] XUN “7 (2A0]8/99) S9XOq 07 JO as¥_ Old# %0'| poop OO1/S6'S$ S2AO[H UONBUTUEXG [BUI] XI J-O1g “| » SLOadaq | S§ONILVY | LSOO TIVLAY TUAaWOAN UACUO F AWVN AAOTO AAOTO TVOINITO Ga.Lsapons TGALSAL SAAOTD 'S “VuO Aq pajsa} asouj se sures 9q jou ABUT soAo]d asned0q po}st] aso} UBY} Joy} SIO;NGLAsIp Woy Sutseyond ft peYO aaoge UO soaoj3 aseyoind 0) ZuNdwIaYe JI [NJare9 og ‘NOLLN¥KD ‘PSUTULIS}op UBSUT [[PIOAO UB w? (p=100g ‘E=He J “T=POOH *| =JU][90xq) Ajoyesedas popesd asm (q) | Wot “| o8ed uo poyst] SoNsUa}oRIeYO JworuN]O / Jo yor § ‘spojep BuULMjoORINUBU MOT WZ ‘SoNSLIa}ORIeYD [BOTT] Pood []BIOAO “JSOd a] qeUOseaI Jo UONLUIQWIOD PRY JeY) SUONENIBAD 76, F 16, HOG WOY SdA0[3 sayeoIpuy ‘Oped jSoq = JOqUMU MO’] ‘soAoT3 jo S9X0q € Ul Spajop BULMjORINUBU UeoUI ap ‘soNSUIA}OBIBYO [ROTUTID / “soo ssor0e BuIseIOAR JO [NSAI st BuNRI [[eIOAG = oo (ea0[8/95"S 1) oe Sax0g (| JO ase_ 90L86b- 18884 ea - %Y'p ie J OOL/0S'SI$ SOAO[H UeXy Xow] IqUIY XOyeHEN “PZ Se (2a0[8/9¢ 1) : S9X0q (7 JO ase_ Ws009# MP'Z poop 001/00'S I$ S2A0[H X2Q-N [WIN “€Z . (2a0[8/9¢°9) = S9X0g (| JO ase5 7-Xa# 1 %8 poop O01/0S'9$ SOAO|) UORBUTUTEXY X9}B] JOOHOLY “77 oS (0n0]8/9Z1) S98-Ob# : S9X0qg OQ] Jo sseD S9A0TDH YE poop OOL/SE' IIS WEXy X9}B] WSTY/Yo'] Yonoj end “[Z (2A0]8/92 01) S9XOG (| JO 9S¥D IZLS B IPLs# ME] ie J OOV/L9'O1$ S9AO[H [BOIPSY] Xaye'] YON] -O1IY ‘OZ (2078/21) vpOOI-D'l ¥ £001-D T¥ SOX0qG 0Z jo ose*) S9AOTH) UOTNeUILe XxX] = %Y"p pooy 001/S6'9$ Xo}e'] Otusd Ja]; y-odAH puajog “6 | ie) é: (aa0[8/99) ZOLO# Qa, SOX0qQ Ol jo ase SSA0[H ey A” ty od a e ~ 2 ae O : mH 3 QO 4 Ww * _ wn - —| awn 2 a) es La ye m © i. 7 * =) c? “=z Z es) on o an * at ~” a ‘o) i ro! . ce a1 ig 7 oe — fe) v2) 4 qd o S| V SHAOTS ONILVUAdO AO NOILLVOIVAT App. 77 TEST RESULTS BY GLOVE TYPE: Ie LATEX GLOVES - Most gloves tested met, or came close to meeting, -4¢ clinical experiments,4” and documentaries.** Reports such as these make it impossi- ble to rule out environmental surfaces as fomites. App. 127 Until data become available to demonstrate con- clusively that contaminated environmental surfaces can- not transmit infections, clinicians cannot ignore or treat them lightly. As dental operatories have innumerable environmental surfaces that are contaminated during routine patient treatment, the effectiveness of products used to disinfect these surfaces must be examined. This investigation was conducted to test a number of commer- cial products to identify those with broad-spectrum, rapid antimicrobial activity both in the absence and pres- ence of bioburden. Methods and materials The general protocol specified use of four test methods and five test organisms with 39 disinfectants in the absence of bioburden. Disinfectants demonstrating best antimicrobial activity under these conditions were then tested with the same methods and organisms in the pres- ence of bioburden. Disinfectant selection and preparation Table 1 lists the disinfectants selected for this study based on a product-use survey,4? manufacturers’ communica- tions, and literature review. All products were prepared according to manufacturers’ directions immediately before testing. When dilution was specified, sterile deionized water was used. App. 128 Test organism selection and preparation Test organisms were: Pseudomonas aeruginosa ATCC 15442, Salmonella choleraesuis ATCC 10708, Staphylococcus aureus ATCC 6538, Mycobacterium bovis (BCG) ATCC 35743, and poliovirus type I (Mahoney strain). The four bacteria were selected because they are specified as test organisms by the Environmental Protection Agency (EPA) to register hospital disinfectants and to establish tuberculocidal claims.*! Poliovirus I was selected because it is resistant to inactivation by many disinfectants.5?-4 Bacteria were prepared according to EPA specifica- tions, except stock cultures were stored in liquid nitro- gen. Poliovirus was grown in HeLa cells, harvested by multiple freeze/thaw cycles and cesium chloride (CsCl) banding, and stored at 4 C in CsCl. Test methods Association of Official Analytical Chemists Use Dilution Method (AOAC UDM). The standard AOAC UDM, using 60 stainless steel penicylinders per replicate, was per- formed precisely as described in AOAC literature.5° Sec- ondary subculture was performed on each carrier and both subcultures were incubated at 37 C for 48 hours. For bioburden testing, the same method was used except penicylinders were coated with 50:50 vol/vol mixture of human whole blood and bacterial culture. Environmental Protection Agency Tuberculocidal Activity Test Method (EPA TB ATM). The standard quantitative EPA TB ATM was performed precisely as specified in EPA literature.°! For bioburden testing, the same method was Fe Oe Gite ee a Coe, Pe SA ee EN OEE eo Ra Ke Lae MON ag ee a aN i RAE Pas a Se a rs ~ ee a a ee Me LI NY ae oe ie ‘ both Soa ae wae oat a Pea 2 log, units). Tests performed without blood used 100 uL of virus, 210° plaque-forming units (PFU), added to 900 pL of disinfectant. After prescribed contact times, phosphate-buffered saline solution was used for serial 1:10 dilutions, and four consecutive dilutions of virus were assayed in duplicate on monolayers of HeLa cells for infectious poliovirus. Twelve-well plates (12-Well Tissue Culture Cluster 3512, Costar) were incubated at 37 C for 48 hours and stained. Log,,. reductions were calcu- lated from plaque counts. Disinfectants yielding three log, reductions in virus titer were evaluated for interfer- ence with virus attachment to HeLa cells. Each 12-well plate included controls to assay for titer of viral challenge and test for system contaminants. Also, disinfectant cyto- toxicity to HeLa cells was determined. In cases in which cytotoxicity was detected, dilution was used to eliminate this effect. Dilution was also used to eliminate the effect of residual disinfectant on the virus in the assay system. Testing with human whole blood used the same pro- cedures described except 10uL of poliovirus (210° PFU) was added to 100 uL of blood and allowed to stand for 1 minute before 900 uL of disinfectant was added. Controls were included to determine amount of virus inactivated by blood. For tests in which urea was included to disrupt App. 130 ethyl alcohol-induced blood aggregates, the same pro- cedures were employed except that siliconized tubes (Sig- macote, Sigma Chemical) were used and 9.0 mL of 7.0 mol/L urea was added to the blood-virus-disinfectant mixture after prescribed contact times. Log, . reductions were calculated for all work involving poliovirus (both with and without bioburden) using the formula: log, reduction = logy, (titer of viral challenge per mL) — log, (titer infectious virus per mL after exposure to disinfec- tant). Clinical Research Associates Environmental Wipe Method (CRA EWM). A test was devised to mimic dental clinical procedures used for disinfection of environmental sur- faces to determine if wiping with disinfectant-soaked gauze sponges inactivated organisms dried onto surfaces, both in the absence and presence of bioburden. Silicone adhesive (Mirror 3 Tray Adhesive, Kerr/Sybron) and caulking (Silicone Il GE5070, General Electric Co) were used to attach an 8!/1®© x 117/® in piece of laminated plastic counter covering (1595-6 Black Wilsonart, Ralph Wilson Plastic Co) to 8!/* x 12-inch polypropylene trays (Size B Trays 202401, Zirc Dental), which were trimmed to fit snugly under their polyethylene lids (Tray Cover 202441, Zirc Dental). Figure 1 shows the test tray after construction and before inoculation with test organisms. Lids and trays were sterilized with ethylene oxide (ETO) for 2 hours at 135 F and aerated for 8 hours before 2 mL of bacterial suspension was applied with a sterile 2- x 2-in cotton filled gauze sponge (Cotton Filled Sponges 6000207, Healthco). After the organisms applied to the trays were completely dried (20-30 minutes) in a laminar App. 131 flow hood (NU-408FM-600, Nuaire), 3.5 mL of disinfec- tant was pipetted onto a sterile gauze sponge which was then used to wipe the test surface for 10 seconds using about 150-g pressure with overlapping strokes (20 left to right, followed by 20 top to bottom). Disinfectants sold in aerosol spray cans were treated in the same manner to standardize the amount of disinfectant delivered to the contaminated surface by spraying the disinfectant into a sterile test tube before pipetting. After wiping, the disin- fectants were left on the trays for 3 minutes before one of two methods was used to determine the number of viable organisms remaining on the tray. The method depended on the test organism. M bovis coated trays were flooded with 50 mL of tryptic soy broth (TSB) with neutralizers (ingredients are enumerated in section on media and neutralizers), and scrubbed for 1 minute with a sterile polypropylene brush (Nail Brush 501, Kellogg Brush Co) to remove and sus- pend viable organisms. The fluid was collected and diluted, and duplicate 1-mL samples of each dilution, plus the undiluted fluid (approximately 40 mL), were passed through a 0.45-um filters. Each filter was washed twice with 100 mL of sterile 0.1% peptone water, placed on Mycobacterium 7HIl agar, and incubated at 37 C for 21 days. To allow calculation of log, ) reductions, trays wiped with water were included in all tests. Log, reduc- tions were calculated using the formula: log,, reduction = log,, (number of viable organisms from water control tray) — log, ) (number of viable organisms from test tray). P aeruginosa, S choleraesuis, and S aureus remaining viable organisms were assayed directly on the trays by adding 300 mL of tryptic soy agar (TSA) with neutralizers App. 132 at 45 C. Trays were covered with their lids and incubated at 37 C for 48 hours. Colonies were counted, with > 500 designated as “too numerous to count” (TNC). Trays wiped with water were included as organism viability controls. Results of this testing were reported two ways: by the number of colony forming units (CFU) for each of the three test bacteria that survived disinfectant treat- ment, and as percent of tests less than TNC. To determine the percent of tests less than TNC for a particular disin- fectant, the following formula was used: percent of tests less than TNC = number of tests less than TNC for the three organisms + total number of tests x 100. To deter- mine the mean percent of tests less than TNC for a category of disinfectants with the same active ingredient, the mean of all disinfectants within the category was calculated. The CRA EWM bioburden testing with all four bacte- ria used the same methods, except cultures were mixed 50:50 vol/vol with human whole blood; 1 mL of this mixture was spread on trays with a sterile glass rod. For tests with S aureus and M bovis in which urea was included to disrupt blood aggregates, the procedures described previously for M bovis were used except that 50 mL of 7.0 mol/L urea was substituted for TSB used to suspend organisms from the surface. Media and neutralizers For M bovis, TSB (Difco) containing 1% Tween 80 (Fisher Scientific), 1% lecithin (Sigma), and 0.4% sodium thiosul- fate (Sigma) were used in CRA EWM tests, and Mycobac- terium 7H11 agar (Difco) was used for all subcultures. App. 133 For P aeruginosa, S choleraesuis, and S aureus, TSA (TSB + 1.5% Bacto-agar, Difco) containing 0.5% Tween 80, 0.1% lecithin, and 0.1% sodium thiosulfate was used as the subculture medium. Minimum Essential Medium (Irvine Scientific) supplemented with 10% calf bovine serum enriched with iron (HyClone) was used for HeLa cell cultures. Selection of bioburden and procedures used for testing with bioburden Because of its clinical relevance, human whole blood was used as the bioburden challenge whenever possible. A concentration of 50% human whole blood in the blood- bacterial suspension mixture was used with the AOAC UDM and CRA EWM tests performed with P aeruginosa, S choleraesuis, and S aureus. A 10% concentration of human whole blood was used with virus suspension tests because higher concentrations precluded proper mixing and pipetting with some disinfectants. Two different types of bioburden were used with M bovis to accommo- date test method differences. A 50% concentration of human whole blood in the bacterial suspension was used in the CRA EWM tests with this organism, and 5% horse serum in the bacterial suspension-disinfectant mixture was used in the EPA TB ATM tests. Five percent horse serum was used because it has been specified as the bioburden for other standard EPA tests.°° Use of human whole blood as the bioburden required special procedures when ethyl alcohol-containing disin- fectants were used because they caused the organism- media-whole blood mixture to form aggregates. Different App. 134 chemicals were sought to disperse the aggregates without affecting viable organisms, and 7.0 mol/L urea met the criteria best.°° Although 7.0mol/L urea destroyed gram- negative bacteria, it allowed almost complete recovery of M bovis, S aureus, and poliovirus. Therefore, when ethyl alcohol disinfectants were tested with whole blood bio- burden, the CRA EWM tests using S aureus and M bovis and suspension tests using poliovirus included the addi- tion of 5}0mL and 9mL of 7.0 mol/L urea, respectively, after disinfectant treatment. The same tests were per- formed without urea so results could be compared. Selection of wipe material As it has been reported that cotton may interfere with the antimicrobial activity of iodophors,’ this was also evalu- ated. For this test, sterile GSA centrifuge bottles contain- ing 64 mL each of Biocide and Wescodyne iodophors diluted 1:213 received 8 g of three different wipe mate- rials (Cotton-Filled Gauze Sponges by Healthco, Nu- Gauze rayon/polyester sponges by Johnson and Johnson, and Viva Paper Towels by Scott Paper Co.) After 10 minutes, samples were centrifuged for 20 minutes at 6,000 x g. An aliquot of 9.9 mL was removed from each GSA bottle and 0.1 mL of S aureus culture was added. Assays for viable organisms were performed at 3 min- utes. Tests for chemical interference and neutralizer efficacy To assay for possible toxic effects of ETO residuals or materials, or both, used in the CRA EWM, 300 mL of TSA with neutralizers containing about 100 CFU was poured Ee App. 135 into an ETO sterilized CRA EWM tray, a CRA EWM tray disinfected with 70% vol/vol denatured ethyl alcohol and not ETO sterilized previously, and several large sterile petri plates (150 x 15 mm). Tests used three replications each of P aeruginosa, S choleraesuis, and S aureus. To test efficacy of the neutralizers in TSB, 1 mL of each disinfectant was added to 9 mL of TSB with neu- tralizers. After 1 minute, about 100 CFU of M bovis was added. Thirty minutes later, the suspension was filtered and subcultured on Mycobacterium 7H11 agar. Efficacy of the neutralizers used in TSA was evaluated by wiping CRA EWM trays with disinfectant, waiting 3 minutes, then filling the trays with TSA plus neutralizers contain- ing about 100 CFU. Reproducibility of the wipe test To determine reproducibility of the mean organism chal- lenges applied to CRA EWM test trays both without and with blood, results from water control trays were exam- ined. Reproducibility of CRA EWM test procedures was examined when two different technicians performed the test with M bovis mixed 50:50 vol/vol with human whole blood; diluted Clorox (1:5) was the disinfectant. Tests were performed in parallel, and the technicians alter- nated tray treatment to correct as much as possible for time. App. 136 Results Comparison of data from four different test methods Figure 2 includes the data from all tests performed in the absence of bioburden. Disinfectants are grouped by main active ingredient to condense the data to facilitate com- parison of results obtained with the four different test methods (AOAC UDM, EPA TB ATM, CRA EWM, and suspension tests). The data show a close correlation of results obtained with the EPA-specified test methods (EPA TB ATM and AOAC UDM) compared with the wipe test method (CRA EWM). Significant differences’ were evident only with iodophors tested against M bovis. With this particular disinfectant-test organism combination, the suspension test method (EPA TB ATM) was signifi- cantly more permissive than the surface wipe test method (CRA EWM). Antimicrobial activity in the absence of bioburden Table 2 lists the detailed data by CFU and PFU under each of the five test organisms for all 39 disinfectants tested in the absence of bioburden. When these data were combined under the primary active ingredient of each disinfectant (Fig 2), it became apparent that overall, in the absence of bioburden, ethyl alcohols and chlorines pro- vided best inactivation of all five test organisms, regard- less of the test method or contact time used. lodophors had intermediate activity. Although they performed well against the virus, they failed to kill M bovis dried on plastic laminate surfaces, and they had low activity against the three EPA-specified bacteria. Isopropyl alco- hol, alcohol mixtures, dilute glutaraldehyde, phenolics, App. 137 and quaternary ammonium compounds all failed to inac- tivate poliovirus, regardless of the contact time used. The glutaraldehyde and quaternary ammonium compounds also failed to kill the TB organism. These data also showed: (1) disinfectants could kill the three EPA-specified organisms using the 10-minute EPA specified test (AQAC UDM) and not inactivate resi- stant organisms with clinical significance such as TB (dilute glutaraldehyde and quaternary ammonium com- pounds) and poliovirus (isopropyl alcohol, isopropyl- ethyl alcohol mixtures, dilute glutaraldehydes, phenolics, and quaternary ammonium compounds); (2) disinfectants that killed the TB organism did not always inactivate poliovirus (isopropyl alcohols, isopropylethyl alcohol mixtures, and phenolics); (3) poliovirus was resistant to inactivation by several types of disinfectants regardless of contact time (isopropyl alcohol, dilute glutaraldehyde, phenolics, and quaternary ammonium compounds). Figure 3 shows the performance of each of the 39 disinfectants that were included in the means reported in Figure 2. The data range within each of the eight disinfec- tant categories is also apparent. Antimicrobial activity in the presence of bioburden Table 3 shows results of CRA EWM and suspension tests performed on the 11 disinfectants selected for testing in the presence of bioburden. These data illustrate the adverse effect of whole blood on disinfectant anti- microbial activity. Tests with eight of the 11 disinfectants produced TNC counts when blood was added to the cultures. Only Citrace, Lysol sprays, and 70% vol/vol App. 138 denatured ethyl alcohol had consistently high anti- microbial activity across all five test organisms — both in the absence and presence of bioburden. Figure 4 gives a graphic representation of the data in Table 3. In Figure 5, the 11 disinfectants listed in Table 3 have been grouped by active ingredient to display effects of the different types and concentrations of bioburden (10% and 50% human whole blood and 5% horse serum) used with four different test methods. Overall, the ethyl alco- hol category performed best regardless of test method, type or concentration of bioburden, or test organism used. The chlorine category showed high activity against poliovirus, but activity against M bovis and S aureus was dependent on type and concentration of bioburden used. Whole blood (50%) caused a significant decrease in anti- microbial activity of chlorines, whereas horse serum (5%) did not interfere with antimicrobial activity. Both brands of iodophor had very low activity across all five test organisms in the presence of all types of bioburden. Fig- ure 6 shows the appearance of CRA EWM trays and the EPA TB ATM filters after treatment with Lysol sprays, and Biocide and Wescodyne iodophors. Figure 7 shows results of tests performed with and without 7.0 mol/L urea, which was used to dissociate aggregates formed when ethyl alcohol products inter- acted with whole blood bioburden. Separate assays were performed both with the aggregates intact and after dis- sociation by urea. The goal was to determine if logj, reductions were caused by disinfectant kill or entrapment of viable organisms within the aggregates. The data in Figure 7 indicate entrapment of viable organisms was not generally a problem. Overall, log,, reductions after urea Distt a App. 139 treatment were equal to or higher than tests not including urea, indicating that these ethyl alcohol disinfectants pen- etrated the whole blood and inactivated the organisms within. Antimicrobial activity related to contact time Figure 8 shows effects of 3-minute versus 10-minute disinfectant contact times in the absence and presence of human whole blood. Generally, increasing contact time made little or no difference in the antimicrobial activity of the four disinfectants tested. Both Biocide and Wescodyne iodophors had almost no disinfectant activity in the pres- ence of blood, even when 10-minute contact times were used. On the other hand, Citrace and Lysol sprays pro- duced greater than 3 log, reduction for all five test organisms both at 3- and 10-minute contact times and in the absence and presence of whole blood. Therefore, Cit- race and Lysol spray were selected for testing at shorter contact times of 2 and 1 minutes. Figure 9 shows the rapid antimicrobial activity of Citrace and Lysol sprays. In the absence of whole blood, they produced 2 log,, reduction of all three test organ- isms in 1 minute. With whole blood present, both disin- fectants produced 2 2.8 log,, reduction in 1 minute. With increased contact time, a general increase in kill was achieved. Antimicrobial activity related to wipe material Figure 10 shows results from tests of the hypothesis that cotton in gauze sponges used to wipe surfaces interferes App. 140 with the antimicrobial activity of iodophors.® These data show that iodophor antimicrobial activity was inhibited by paper towels, but cotton and rayon/polyester had no adverse effect at the 3- minute contact time. Tests for chemical interference and neutralizer efficacy Table 4 shows results of work performed to test for chem- ical interference of residuals from ETO sterilization and/ or materials used to construct trays used in the CRA EWM. Colony counts of the three test organisms showed inhibition of less than 6 CFU compared with control counts, which indicates that no toxic effects resulted from either variable. Table 5 reports on efficacy of the neutralizers used in the CRA EWM procedure. The data show adequate neu- tralization of all products except quaternary ammonium compounds. Although residual activity was present to a small degree with quaternary ammonium compounds, it was not considered a problem because even with this advantage, these products failed to inactivate M bovis in the absence of bioburden. Reproducibility of the wipe test Reproducibility of the viable organism challenge on CRA EWM rays was demonstrated by the similarity of numbers of organisms computed from water control trays. The mean log,, challenges of 52 (without blood) and 34 (with blood) TB water control trays were 6.01 + 0.22 and 6.57 + 0.15, respectively. i aki a a App. 141 Table 6 shows results of reproducibility tests per- formed on the CRA EWM. Average log,, reductions for M bovis achieved by two technicians using Clorox 1:5 in three test replications are shown. These data were consis- tent both within and between technicians. Discussion The goal of this investigation was to identify environ- mental surface disinfectants that had broad-spectrum antimicrobial activity, rapid action, and effectiveness both in the absence and presence of bioburden. Only Citrace, Lysol sprays, and 70% vol/vol denatured ethyl alcohol met the criteria, regardless of the test method or contact time used. Chemically, the two commercial products are similar. Citrace contains 66.6% wt/wt denatured ethyl alcohol (SDA-40-1), 0.12% ortho-phenylphenol, sodium nitrite rust inhibitors, proprietary deodorizer, and 3.5% hydrocarbon propellant (personal communication, Calvin Goeder, Caltech Industries, 1988) and Lysol sprays con- tain 79.0% wt/wt denatured ethyl alcohol (SDA-40-1), 0.1% ortho-phenylphenol, rust inhibitors, N-alkyl-N-ethy] morpholinium ethylsulfate deodorizer, and carbon diox- ide propellant (personal communication, Joe Rubino, MS, Lehn and Fink, 1988). Concentration of ethyl alcohol appeared to be a criti- cal factor. Other products with formulations similar to Citrace and Lysol sprays, but containing less ethyl alco- hol (CoeSpray with 53.5% wt/wt ethyl alcohol and Pro- Cide ES with 52.8% wt/wt ethyl alcohol), failed to inactivate poliovirus in the presence of bioburden (Table App. 142 3). These findings led to special tests performed to inves- tigate the antiviral activity of various concentrations of SDA-40-1 denatured ethyl alcohol used in Citrace and Lysol sprays in the presence of 10% whole blood. Results showed a dramatic increase in virucidal activity with alcohol concentrations equal to or greater than 70% wt/ wt. Klein and Deforest5? reported similar results with poliovirus I. Also, many other investigators have reported very rapid inactivation of both viruses and bac- teria with ethyl alcohol in concentrations of 70%-95'%.52.97-©5 However, clinicians and researchers can be misled about alcohol concentrations in commercial products if they do not understand the volume/volume and weight/weight designations. Antimicrobial activity of high concentration ethyl alcohol can become unpredictable if storage conditions allow undetected volatilization, environmental use condi- tions cause extremely rapid evaporation, or interfering denaturing agents are used. Unfortunately, clinicians have no way to monitor these variables. Therefore, Cit- race and Lysol sprays appeared better suited than ethyl alcohol alone for environmental surface disinfection in clinical settings because they are sealed in airtight cans to prevent volatilization during storage; they contain other ingredients in their formulations that delay evaporation during use; and their denaturing agents are standardized. Currently, official agencies and others recommend use of iodophors,42°*7! chlorines,542,5°69.72-75 and phe- Lad , nolics”? for disinfection of environmental surfaces. Results from this investigation suggest further review of these recommendations. This work showed iodophors had very poor antimicrobial activity in the absence and App. 143 presence of bioburden, regardless of the test method or contact time used. Horse serum and paper towel material caused iodophors to lose almost all activity. Many others have reported problems with iodophor antimicrobial activity on inanimate surfaces.°2%,768! With chlorines, the potential of bioburden to diminish antimicrobial activity has been mentioned by many investiga- tors>?,63,78.82 and this problem was further demonstrated in this study. The failure of different phenolic formula- tions to inactivate poliovirus using both 3- and 10-minute contact times was also demonstrated, and this problem has been noted by others.® 6353-85 In addition, this study confirmed previous reports citing inability of isopropyl alcohol to inactivate pol- iovirus,°*-5° problems with antimicrobial activity of dilute glutaraldehyde,*’ and inability of quaternary ammonium compounds to inactivate poliovirus°****4 and the TB organism.78.55 Precleaning of surfaces before disinfectant use has been stressed.4!,70.71,7389-94 In the past, detergents have been preferred for this process. The obvious intent is to decrease proteins and other debris that interfere chem- ically with the antimicrobial activity of disinfectants. Although theoretically this appears sound, use of cleaners with low antimicrobial activity before disinfec- tant application causes cleaning personnel to touch con- centrated body fluids containing potential pathogens. It ignores the fact that the wiping action can spread mate- rial from smaller concentrated areas to larger areas, and onto the wipe material and the person performing the cleaning. Now that disinfectants have been identified that penetrate and kill microbes within heavy bioburden, it App. 144 seems prudent to apply these agents first to a lower organism loads before human contact. Disinfectants con- taining high ethyl alcohol and ortho-phenylphenol can be used first to preclean and the disinfect in the following regimen: wet surface well and allow 2-3-minute disinfec- tant contact time to lower viable microbial load within debris; wipe vigorously to clean surfaces; rewet surface and allow 2-3-minute contact with disinfectant after cleaning. Appropriate barriers should be worn by clean- ing personnel when using the suggested method. Four clinically relevant points were demonstrated in this study: — Disinfectants often have selective kill. Although clini- cians have been advised that tuberculocidal products can be depended on to kill other important pathogens,% this is not necessarily true. In this study, for example, 70% vol/vol isopropyl alcohol and the phenolic, Sporicidin Spray, produced profound kill of the TB test organism (M bovis), but failed to inactivate a resistant nonenveloped virus (poliovirus). This questions the assumption of broad-spectrum kill, based solely on any one organism. —- Dilution generally decreases disinfectant activity. This effect is seen in both chlorine and iodophor categories (Table 2). Although there are reports indicating dilution increases the antimicrobial activity of iodophors,% this study showed activity decreased as dilution was increased from 1:106 up to 1:213. The same was true of chlorines as dilution was increased from 1:5 up to 1:20. - Bioburden affects disinfectants adversely. The delete- rious effect of bioburden on antimicrobial activity was demonstrated repeatedly and with all disinfectants in this App. 145 study to varying extents. Citrace, Lysol sprays, and 70% vol/vol denatured ethyl alcohol were affected least. - Many commercial products have marginal activity. This point was illustrated by the fact that 28 of the 39 products in this study failed one or more test organisms even in the absence of bioburden. Only three of the 11 products tested in the presence of bioburden inactivated all five test organisms, regardless of the test method used. Reproducibility of the AOAC Use Dilution Method has been debated for many years. In this investigation, the 60-tube version of this test was performed 230 times on 39 different products representing eight different active ingredients. When results were arranged in order of disinfectant major ingredient (Table 2), it became apparent that the AOAC UDM was reproducible when disinfectants with definite high antimicrobial activity were tested. However, when disinfectants with marginal activity were tested, variability of results increased sub- stantially. To see this pattern, it was necessary to test several representative products from each of eight major active ingredients. Conclusions Data from this investigation indicated that optimum dis- infection of environmental surfaces was highly formula- tion dependent. Of the 39 products tested, only three inactivated all five test organisms, regardless of test con- ditions. The other products showed deficiencies that con- traindicate their use, in the formulation tested, as environmental surface disinfectants in clinical dental set- tings. App. 146 Information about the manufacturers of the products mentioned in this article is available from the authors. Neither the authors nor the American Dental Association has any commercial interest in the products mentioned. The authors thank Ms. Debbie Cox for initial devel- opment work; Ms. Christine Rhodes and Mrs. Barbara Ericson for technical assistance; Mr. Ken Higbee and Melvin Carter, PhD, Brigham Young University Center for Statistical Research for statistical analyses; Ms. Jan Scoggin and Brigham Young University instructional graphics department for art work; and Mrs. Judy Davis for preparing the manuscript. Dr. Christensen is director, Clinical Research Associ- ates, 3707 North Canyon Road, no. 6, Provo UT 84604. Dr. Robison is coordinator, microbiology section; Ms. Robin- son is microbiologist; and Mr. Ploeger is virologist, micro- biology section; Clinical Research Associates. Drs. Leavitt and Bodily are members of the faculty of microbiology, Brigham Young University, Provo, UT. Address requests for reprints to Dr. Christensen. 1. Belting CM, Haberfelde GC, Juhl LK. Spread of organisms from dental air rotor. JADA 1964;68:648-51. 2. Hausler WJ Jr, Madden RM. Microbiologic com- parison of dental handpieces. Aerosol decay and disper- sion. J] Dent Res 1966;45:52-8. 3. Travaglini EA, Larato DC, Martin A. Dissemina- tion of organism-bearing droplets by high-speed dental drills. ] Prosthet Dent 1966;16:132-9. App. 147 4. Crawford JJ. If saliva were red. 35-mm slide dem- onstration. Chapel Hill: University of North Carolina Dental School, 1979. 5. Autio KL, Rosen S, Reynolds NJ, Bright JS. Studies on cross-contamination in the dental clinic. JADA 1980;100:358-61. 6. Cottone JA. Infection control in dentistry. In: Pro- ceedings, National Conference on Infection Control in Dentistry, May 13-14, 1986. Chicago: Department of Health and Human Services, 1986:36-43. 7. Christensen RP, Robison RA, Robinson DF, Ploeger BJ, Leavitt RW. Infection control in the dental office. Practical Clinical Courses Videos 1, 1987. 8. Crawford JJ. Barriers can minimize threat of occupational exposure to contagions. Dent Today 1987;6:28-31. 9. Madden RM, Hausler WJ Jr. Microbiological com- parison of dental handpieces. Preliminary report. J Dent Res 1963;42:1146-51. 10. Stevens RE Jr. Preliminary study —- air contam- ination with microorganisms during use of air turbine handpieces. JADA 1963;66:237-9. 11. Brown RV. Bacterial aerosols, generated by ultra high-speed cutting instruments. J] Dent Child 1965;32:112-7. 12. Larato DC, Ruskin PF, Martin A, Delanko R. Effect of a dental air turbine drill on the bacterial counts in air. J Prosthet Dent 1966;16:758-65. App. 148 13. Ewen SJ, Glickstein C. Ultrasonic therapy in periodontics. Springfield, IL: Charles C Thomas, 1968:34-7. 14. Micik RE, Miller RL, Mazzarella MA, Ryge G. Studies on dental aerobiology: Bacterial aerosols gener- ated during dental procedures. J Dent Res 1969;48:49-55. 15. Holbrook WP, Muir KF. MacPhee IT, Ross PW. Bacteriological investigation of the aerosol from ultra- sonic scalers. Br Dent J 1978;144:245-7. 16. Christensen RP, Bangerter VW. Subject: oral pro- phylaxis, Prophy-Jet. Clin Res Assoc New] 1981;5:1,2. 17. Pagniano RP, Scheid RC, Rosen S, Beck FM. Airborne microorganisms collected in a preclinical dental laboratory. J Dent Educ 1985;49-653-5. 18. Orton GS. Clinical use of an air-powder abrasive system. Dent Hyg 1987;61:513-8. 19. Christensen RP, Bangerter VW. Subject: air- slurry polishers. Clin Res Assoc Newsl 1988;12:1,2. 20. Horning G. Clinical use of an air-powder abra- sive. Compend Contin Educ Dent 1988;8:652-60. 21. Favero MS AJA %Y%OL oeoeeeec eee seeeeseeeensece poBuyoed se sf) coe eee ewes en eee aqinort Ldasadd ‘LE jousydyAusyd-o “LEO coeervee ener eeseeeeeeeee po8ryoed sv asf) coos eereser esse eseseetesne asiogdd ‘O€ joyooye jAdosdost © ,0¢ joyore Apa e,gg TT co eeereceeees ee padexoed st asf ees ecereseessces O0€ AGIOVINAd “67 yoyooye jAdosdost &%8 | joyooe jAy}2 %BI Cveveoscocesceticeess BeRumed £B C8) +. eeeeeeernese 81 AGIOVWUAd "SZ jousydosojyo-d-]Azuaq-0 %F0'0 jousydjAusyd-o % 870 se eeeeee eeeeeee . . eos tes pace ee eee eee e anne eeeeeeees **TINWO ‘LZ jousydosojyo-d-jAzu9q-0 %EO'O jousydjAusyd-o ~%8T'0 eee eee wee eeeeee stew eee ee Aad | . eee eee ewe eee FdIOLLINW “OZ VLA wWarposenr} %200 0 jousydyAwre-p2)-d %10'0 joyooye jAdosdost &% 10° jousydjAusyd-o %70'0 jousydosojyo-d-jAzu99-0 %pO'O eeeeeeees FACES OTE DOSS OCER meres ee cceeeees sour ES “Ee (JosA’] [euolssajorg yuarg sys] jousydjAusyd-o % 1°09 *** gua2g Ysetg 9UI2g sunday) joyooye jAuye %6L oeoeeeeeeses eee ee pedexoed st asn eee eee ewer eneene SAVudS IOSAT "PZ VLGA Wntposena) %200 0 joyooye Adosdost %¢10'0 jousydosojyo-d-jAzZU9q9-0 %pPO'0 !0 urd %S0'O dvos %91'0 eevee eee eeee eoeeeeenenee ee COrl:l seeee (ju2a2g 2u1g) GINDIT IOSAT ‘€Z yoyoaye Adoadost aja %OL ait yas (a he tees paseyoed se ase) “sees "* WOHOIOTV TAMOUdOSI TZ spunodwios wntuowwe Awwayenb%ogQo 00 Sec wersenesecvscese 9S7:1 TETUrrrrereir i ccsbeese YOL'IH ‘IZ QJBUOSN]T ouIprxoysojyo %¢'O RIE ONO HOE tee paseysed seas “ALLATAMOL LYLSIGIH 07 OPUOTYS WINIPOS %ET O pioe 1ue8J0 rs a Bpbetapriar a 2h inka aly. ti lanedigln tle Pes . S60 SOMERSET a BOR ASS ee WOdSXa ‘6! joyooye jAdosdosi %¢p “ses ope coe cen, ERE sta, aici tiptoe Pisich tid ae jeusuniadrg XIAW IOHOIDTY TAdOUdOSE' TAH LA 81 joyooye jAdosdos! % Op te i oe pe A Ma Ses a Be By Ay Ae As jeyueunsedr gy XIW TOHOOTY TAdOUCOSE'TAHLG “LI joyooye Ayo posnspeuapapayOQe, = =r padeyoed se asp) ‘+ (parmeusp) TOHOITY TAHLA ‘91 joyooye |Ayja pasnyeusp-uouAA%OL padryoed se asl (painjeuep-u0u) JOHOITY IAHLG ‘St ayuoyoodAy winipos ASS!) Coeeeeeeeseseseveeseeser pedeyoed se asp seme eee eee eee eee eesees HOLYdsIa bl jousydosojyo-d-jAZuaq-0 % 00 jousydjAusyd-o IE 1-15 {AS ENESI ARES ORME eee ee Tel ees ewer eer eeeeene JLLAASY LNAG "EI jousydyAwre-9)-d %ppo'o jousydjAuayd-o %9/ 10 2 S10 JUNUISS? %6'() a joyooye jaye %~OP ES véeee bus paw we $0.8 Cees padexoed re) ell RE ed WET Rahal Seton lhe sah at AVUdSAOD “ZI me syopqoodAy unIpOS HOT | TTT tte e ese est esses ovtoo00ttt INAS HSaWd XOUOTD ‘II 2 a}uojyoodAy winipos %7S'0 eva ed backs bee oN > RAS 0 0.65.0 boa oll “-'5°"* ING9S HSAaMd XOUOID Ol siuopyoodAy wntpos % 50" | ahambee nas coon essen eeeeeeeeeees Ory ‘++5** INOS HSaMA XOUOTD *6 ayuojyoodAy winipos %97'0 serene eee eee teepenh gyre eee eee eee enees omoes YORO’ED g syuoyoodAy wWINIpos %7S°O eee ee . ee ‘oul eee ee eee ee XOUOTO *L ayuojyoodAy wintipos %S0'] everesereseseoee ee ee sere eserenee Sil Cece eeeereseseseeeseses XOUOTO ‘9 jousydjAusyd-o %7 19 joyooye SN tate tab fecal da ce eeeees paSeyoed alg Os anne a8 TerrrrrT ‘''** TOWYLIO 'S jousyd (Axousydosojyoip-p‘Z) Z O10] Y9-¢ %L0'0 joyooye JAdosdosi % Q'S WLda wInIposes}>} %EL'G coeeseses eeoveeeseeese pescyoed st asp oe ee eee es essesesreesese Oxvuogd , surpor siqujeav wdd pop Te ettttestetsstttt Sarr tT eee eee qqgIDola “€ auipot ajqeyreae widd ZR oreo ee ee ee eee eer r eee eee eee eee a as | Pe adgiooig y BIIO BIUaSS? %100 0 . V.LGA Wniposeys) % 100 spunodwos wintuowwe Areusajenb nee TRE a shirt Ios eaivleicin goth eo eeeeeeseee 9$7:1 TrCrrrrr rrr eee ee see )-DISVA ‘I (S)LNAIGAYONI FALLOV NOLLNTIG dO NOLLVULNAQNOD ASN GaGgNaAWWNOoAY aWVN GNVUE 12 qF] 24) UO pajzst] UO|NTP-ssn papuawMUOdas 9Y} Je SpUIIPIISUY DAI}IE JO UOPPLAUIIUOD 9Y} S9;BI!PUT UUINIJOD FYBLA Avy OY], “P2zs9} $S9ULZIIZUISIp [[e JO Feu PUIG Aq Buysy peonoqeydyy — | 24"L oes an ' | BEST AVAILABLE COPY t Ts) — ° Zz. ica U Z. oe 4 ei bave bee mm HON? UPOG NEED srry hie HOdSXa 6 SOWWIOdAY WNIPOS %&GN 0 Auedwoy rosty wikerenescat Pe koucto ‘OL A SioHyoodAY WnIPOS *%EE'O Aredasod x050¢) a ae rene I ‘ = 4 | bart cw a PPT PE ben Wel o> as ates So°0 tare) OyooM Mure KEEL hai |: y eT} MM ae gee - (aged) pouedosd-4 Hoe aes + 3 are, SRP Re os i> Us (ym) pouoos A? %E 04 Pei Rese inenclewatess LEAN wh (mym) poyoors |Ain3 %O8 (am) toyoore Ang %eTS aasva-10HOOTv doots | doom | dools | doom | aool | cool |samu |, meron? ant : HM | anoHiM | HM | AnOHLIM | Hum | anonuim | asaa_| ‘S!AN3I038ONI anuov worvn | AULNAOD | NEES BRYN INV LIENOOG i i$31 JOVANNS | SS3L at me iS3i NOISN3dSNS “(onoa W) wenevowo weowOWREN | hewowee THY SLVNOSOVNI ALVOIGN!I LYVHOD NO SSYVYNDS GAN3NOVIE ‘SOS-E6b'611 ‘68, VOWE “le 19 “dH ‘UesUesyYD suONed;Gnd Buymojjo; uF pequosep ase spoyjow jing ‘jj/} SjEADSPeUl Ssjnjijsuos VONSNpsr °'Hoy ES UY] SSs] “UOUSAUGS AG yueseid poojg ejOyUM UeWINY Ysa YM F jNoyWM ‘ajyeoydi4y ul pewuopied sjsaj jusJeyIP ¢ Bulsn sajnujw OL FR ‘Ee ‘| 40) S}UR}IOJUISIP 0} pesodxe swsiueBio 4s9} ,0L jO Ssuononpe °'Ho; se peyode ae syjnsey ‘sjuejsejuisip Auew Aq {14 0} eouRys!So1 umMouy YM suaBoyjed uewny sie Aoy}y esneoseq swsjueGio js0} se posn ase SHI/A ood yg BjIsj5eq sjsojnoseqny ‘SGOHLAW ® SIVINALVIN (wios'smaues2 MMM) aS GaM WYO ees UONPUOJUI Bs0U! JO4 2-61 ‘6, ‘uer JONaISMAN YUD SIJOUDYd *f 2:81 ‘6, JEW saNaISMAN WYO SaULuo|YD Z "4-02 ‘96, ‘AON 40 /SMAN WUD S/OYOo/y *| ‘33S S1Y0d3u Tifd 4o4 LNOGNVH VuO ‘S}sa} je pessed 4 Ajuo aeym sodim 6 Pue ‘s}S9} }]e Ssed jou pP_p Yo!yM JONpold peseqg-epli0;yD Aeeebebeeneebieeee wnjuowwe Asewejenb | ‘s}se} je pessed auou aieym syonpoid poeseq-o}joueyd OQ} ‘s}s9j je passed euou as9ym sjoOnNpoid peseq -as0ydopo| ¢ ‘s}s9} Wye ssed jou pip Yo!yM JouRaD | ‘s}so} Je pessed z AjuO a1eyM SJONPOld peseq-eujsO}YO 6 ‘s}s9} [Je pessed p Ajuo as04yM sjonposd peseqg-joyorje pz sezjsewwNs eyo Buymojyjog “"PyOM ey) JOAO JB WOY SyuB}e;U;sIp Buse; y Hujseysind s| VHO ‘sjuewesnbes asey; Buyeew sjyonpoid Ayyuep] 1 ‘AjyGnosoyy P Ajpides \y4 snus seoepns lequewuosAue JO} SUe}IAjUISIG in io a NaWNC sy Re “ SLNVLOZANISIC ovsgns 4 VINA WNOUIANT eee Wa! DN a ‘ex L i's, Sap ag ae es Seutkalas beg AS SKE tZiZ-9Z2-t08 :euoyg pOSP8 YeIN) ‘OAOIg OF peoy ahaa N LOLE term clrucal ; state} - ev 4 is ” = & 22 2 + £ ye o 3 a 4 g » w . ° — a s ¢ 53 > 9 G — S A) a rf ae) : & 3 > c , 2 — t& o 2 9 £ pee a Av 4 3 a o 2 + % Iw be i -S , & , ® 7 " "fs J = +o > Ww > 2 » E ; o a ~ 3 ° 7 - = > 2 b 2 : & 2 2 a a > v » 2 3 e 4 & E 3 e rt $§ Dw c © = ; 8 Q — » Oo WOT SMSURLM :OYS GaAh LZ4Z-972-L08 :eu0yd pO9PS YEN) ‘OADIg O# peoy UoAUeD ty OLE 6665 ‘S9j1069}e9 [esa 9 jeII9}9eq YOG WoOJj SwisjueBs0 juR\sisal {14 0} [1/23 324} SJONpoid jo asn plone F ‘syue}DajUISIP jo JByUsjOd 114 JO daeMe Og jsnw SUBIDIUIID “yOR] JUs/eASId JSOW 3} SEM SNJIA juRISISA! e SJEAHIeU! OF Ay yiqeuy ‘POSEQG-BUlJO/YD JO joyooje jAyjs seyyE 949M BSOU} jO ||P F “S}sa} |j2 passed J Ajuo pajsa} syuejoajuISIp ES JO ‘SNOISNTONOD VHD S}S@}] //P Passed jonpoid sayeoipul aweu } INPOsd jO Worl ye oe Wee . Tee 00 0 Ups OQ) , 0 Ps TE COE. OE 70 00 wi § (aye) poyoope Adasdos, oy ven _, OD wpe, PONOM-Bid sy L2 0 00 tw ? , 4 es 10 . Nae? | r? _4§ 0 00 uy OF (mym) tounge pAdosdos) 95 PeHOMm-o1g € ee a cs 0 0 up ¢ epyporys vsn rae ta a | EM BET me RM uj | wryvounwe Amwarend %5°0 ee HLOVD-INVS H3dNS 8 i 6 00 0 we Oh \. eyewegd aampog Kero hes-T Eee: PSB \" PRYWOMRBidg _ ys. Te 0 00 00 wen: “Ue , . Pd : v0 una | rusad Xeri mecerss NIGINUOS 00 0 uw O4 epyorss 0 9°0 0 0 uw ec wnyoowwe Arweng %11'4 wsn Ppeyem-eid jon 4 : ° 5 oe epuorysoupAy Mod Lit —— ee 4 2018 /*) S3dIMONI 9 Hoan ¥ 98M B20)0q yeN} Awsds jORAT I Penem oq pyc Keg Tyson ing Kasds joel] ie pewwBesduy Sed grd OU am Gled) AjmaseuRUos “eroge eve ) oyoore une %62 8} 1UsipesBuj BANE BROUM ‘ABIdE JOBAT 10 IW OF YM BUREN S188 JO now PUCDES 8 JO SYFERU | MOHEG Bue JETER JO RY OF YUM BUTDEM Jo BYNeEL “By8e] syedes Uy 70 2e]8M Ly Aq sedyn OY) DOES) VHD .. JOYOO® %O/ 20 Je}8m UES! YIM odim VEdwep AguBr}. ‘e818 suUCnzeup 8 sezQ>eRW ous ‘SpyORS wryvoUUE ArumENd § SpYORDAIDAy hod iim Peieubexdun nore Lop © sow sedun nen 4 ye 4° rt 00 0 : 0 aw unrowwe AreUeTEND 6870 3diM-LULd3SV “bt | | SaddIM (=ym) jouoore doxdos; Ko°64 wey epporys ysn wryuswure Amuseenn Gare FQIDIAVS “bt 0ASVae-WNINOWNY AYVNYSLVNO Y : v0 (ze:1) 00 : ; i RTE Cm Be, ye 00 0 0 7 ELF tat ae Maud : Tae ee ae oe - on (9¢z74) 0 00 iT isauuy-ia x 4 , Bee: [Sa och 2 eae 0 0 00 : Rie: ¥y34 oti SNSHd1L ASH, a | | | Q3SVa-DIIONSHd | | | i 00 BA. AP o uqui O} (esz:a) > 5 — 4 + a er eee — 3NAGODSaM & 70 eP 0 : a nia ee alieks (Enz:4) ‘ 00 0 er + 00 > eR ANVL934NISIO HOHdOGO! “> v 0 é ty re aR RE Se ag tee AOL et : : op wdda| ven PS pir weaieg fe Serna moe 4. a °. ira “ i BALZOGOI 'S 00 ’ 0 uw OF : 00 00 t¢ 00 0 uw £ euro; wdd §/ ysn foneg (e474) i 00 00 0 wi 30190018 z 00 t S ‘ : ‘ ~_ oe a 0 00 00 9 a . v oupel dd 9, yen. ,. hot EBcqoweoe | > i ’ (e1ebe : + ve > Loe “x Porakeuert ene eee Ts: | aasva-3dOHdOdO! + iv< up 04 epvoRs? PeiNp jou —at emprowen AAEERD 5S 7 WeuNOD TROY | LNs TOVISIO ONINYO4 DT 108A “t - ago0018 | Gools | Gools | Goole | Gool™ | Goola | Sanu , ve Pesan Hil | AMOHLIM | HALIM | LOLI LIMA | ANOHLIM. 1831 | (slunaoawonn JALLOY WOrYA | Auinno? | ANYdNOD | JWYN INVLDBENISIO 1831 30v4uNS | S31 NOISN3dSNS | 1S31 NOISN3dSNS ne « x toe , (anon W)wewvous weownaatbans |: ”, Ueubiem) TUM FLVNOFIAVNI SLVOIGNI LHVHO NO SSHVNOS G3N3NOVIG zz: App. 161 REFERENCE NO. 16 Clinical Research Associates Abstract J. Dent. Res. 69:379 #2161 March 1990 Tuberculocidal Activity of Glutaraldehyde & Glu- taraldehyde/Phenol Disinfectants. R. Robison, D. Rob- inson, B. Ploeger, & R. Christensen (Clin. Res. As. Provo, UT USA) Recent studies have established the inability of glu- taraldehyde (glut) disinfectants to kill Mycobacterium tuberculosis (TB) rapidly. This deficiency has been dimin- ished by raising the glut concentration from 2% to 3.2% & by addition of phenols. The purpose of this study was to compare the tuberculocidal activity of several glut & glut/phenol disinfectants. Products tested were: Cidex7; Cidexplus; Metricide Plus 30; ProCide 30; Sporicidin diluted 1:2, 1:8, & 1:16; Sterall undilute (UD) & 1:4; & Wipe Out UD & 1:2. The EPA Tuberculocidal Activity Test Method (quantitative) was used & linear regressions were performed to establish the time needed for a 6 logjy reduction of M. bovis (ATCC #35743) for each disinfec- tant. All products were tested once a week for 6 weeks to determine tuberculocidal activity & amount of glut & phenol present. TB kill time ranges from initial use to 6 weeks, ordered most to least effective, were: Sporicidin 1:2 = < 1 min; Wipe Out UD = 3 to 4 min; MetriCide Plus 30 = 21 to 28 min; Cidexplus = 22 to 42 min; Procide 30 = 28 to 42 min; Cidex7 = 29 to 58 min; Sterall UD = 36 to 42 min; Wipe Out 1:2 = 35 to 63 min; Sporicidin 1:8 = 53 to 58 min; Sporicidin 1:16 = 192 to 254 min; & Sterall 1:4 = 340 to 399 min. It was concluded that the tuberculocidal activity of combination glut/phenol preparations was superior to glut- App. 162 only preparations & water dilution recommended by manufac- turers affected both types of formulations adversely. App. 163 REFERENCE NO. 17 VOLUME 15, ISSUE 5-- MAY 1991 CRA NEWSLETTER ) SUBJECT: DISINFECTANTS, INSTRUMENT IMMER- SION Today heat sterilization is required for critical instru- ments because it provides best possible margin of safety against cross contamination. However, some items will not tolerate heat, & submersion in liquid disinfectant is highest level of treatment possible. Cli- nicians have difficulty selecting disinfectants because they have no way to know if expected microbial kill is achieved. Although agencies such as EPA, FDA, & ADA have responsibility to monitor claims, none actually test products. Their registration & approval programs are based on data submitted by manufacturers. CRA questioned accuracy of glutaraldehyde & glu- taraldehyde-phenolic claims because apparently similar products had very different claims for test organism kill times, optimum dilution, & reuse life. Therefore, it was decided to perform tests to determine relevance of cur- rent label & promotional information on glu- taraldehyde-based instrument immersion disinfectants. Following report includes: (1) goals of CRA testing; (2) results of testing; & (3) CRA conclusions. 1. GOALS OF CRA TESTING. Purpose of tests was to determine of differences exis- ted among several glutaraldehyde-based disinfec- tants. 10 formulations sold under 12 brand names were tested at various dilutions (total of 18 solutions). Tests included EPA Tuberculocidal Activity Test App. 164 Method (using Mycobacterium bovis ATCC #35743) to evaluate tuberculosis (TB) claims & a conventional suspension test (using poliovirus I, Mahoney strain) to evaluate poliovirus (polio) claims. These 2 organ- isms were selected because of their known resistance to inactivation by glutaraldehyde. Viruses of current interest to dental clinicians, such as HIV & HBV, were not used as test organisms because of technical diffi- culties they present in tests & because they have been shown to be readily susceptible to inactivation by most common disinfectants. Organic stress was not used because it is not required by EPA to validate organism claims. 2. RESULTS OF TESTING. Chart on pages 2-3 gives details of this evaluation. Below is summary of results. (a) TUBERCULOSIS TEST RESULTS - 12 of the 15 solutions with a TB kill claim required longer contact times than listed on their label to pro- duce EPA required reductions. (b) POLIOVIRUS TEST RESULTS - 10 of the 15 solu- tions with a polio claim required longer contact ) times than listed on their label to produce EPA required reductions. (c) TUBERCULOSIS PLUS POLIOVIRUS TEST RESULTS - 4 of the 18 solutions tested fulfilled EPA requirements for both TB & polio through the last day of their reuse life claim in less than 30 minutes (Sporicidin 1:2 & 1:4, Cidexplus, & ai App. 165 Metricide Plus 30), & 7 more fulfilled these crite- ria in less than 60 minutes (Cidex 7, Procide, Metricide 28, Wipe Out not diluted, Banicide & Sterall not diluted, & Sporicidin diluted 1:8). (d) TUBERCULOSIS KILL DID NOT NECESSARILY INSURE INACTIVATION OF POLIOVIRUS & VICE VERSA - Clinicians have been lead to believe kill of the TB organism signals kill of all other pathogens. CRA has reported previously that this is not true (Christensen, et al., JADA 119:493 Oct. ‘89). It is critical to note that 5 solutions in this evaluation required time beyond . TB kill time to inactivate polio (Sporicidin diluted 1:16, 1:8, 1:4; Wipe Out not diluted; & Wipe Out diluted 1:2). 3. CRA CONCLUSIONS: (a) Disinfectants with similar active ingredients had equivalent performance despite diverse label claims. (b) Clinicians need to increase contact times well beyond conventional 10 minutes to assure inactiva- tion of resistant organisms. (c) Increased contact times were always associated with increased dilution of active ingredients. (d) All 18 solutions tested inactivated both test organ- isms to levels required by EPA, if clinician is will- ing to tolerate whatever contact time data indicate. CRA recommendations on specific brand names tested are listed on page 3. App. 166 SWSIN VOUO LSAL SQUIAOIIOd ¥ SISOTNONAGAL TID OL aqqauinowdd FALL SOUT) PI}EIS SAIANJILINUCUT “SA $}[NSIA 389} YYD Lo. Gre eis 6 URED ¥ wt sa VeO Wig] (922 Ay SUOTOsIp ood 1yus sod WwW P9 S21 VYAO 907 = UONNIpP sup @) ZoASOD poieyoed UW OT 299s IIA prt ‘HemMoD skep 87 opAyapyeseinys %00 7 SB Pes() apAyapyeseiniy al AGIOINWO ‘TI weg SVU QUOU (931 LY suonpasip ood ayeusyd uimipose%¢1'O | “wed OH Ww Os SVU J1b = uoNNTp si) @) ZosoD jousyd %g8'0 sured oousyd QUOU 1921 FY Aidsyuaqyysy sAEp Of apAyapyeseinys % 570 L pany -opAyrppeseiniy aL 8:1 NIGIONYOds “Il wW LSA VUD UWI OF :920J 4pY suoTPpotp ood “ap aed W gb IS VAO 407 = UoNNTIp sys @) ZopsoD podeyoed Wi QI 2903 FY ‘pr ‘Hemp shep 87 opAyopyeseinys %00'Z S¥ Posy) opAyapyeseinioy al aqgiooud ‘Ol Lb cp 3 VUO Wi OT :904 YN suoNrasIp onod “agus sod W Lb S91 VAO IZ = UONNIIP sty) @ Zonsoy podeyoed W OE 2907 YW Vopperesjoo skep Tp opAyrapyeseInis %%00'7 SY Posy) opAyapyeseniy a TIVUaLS 6 be pp sr VO Ww OT 2904 BW suoTpesp ood “ay Jed ' W bp SVU 487 = VORP sip @) ZoAS05 podeyord W OE 1994 IN yeoseg sAep Zp apAyapyeseinys %00 7 wren opAyepyezeinig, al AGIOINVa 8 wg S89 VAD Ul QI :904 BY suotpasip ood ‘ayus sod woe asVvHNo | Pl = vonnp snp @ zopsog podeyoed W QT 2901 xonoW sAep OF opAypyeseinys %00 7 SB pos) apAyapreseynysy aL 8TAGIONLAN “L Ww 9 8 YAO Wi OT :994 JW suoTpesIp o1jod “agus sod bw se 7 VO IZZ = VORNIIP sip @) Zopsoy podeyoed Ul 06 2994 JIN TROIPOW £79E Shep 87 apAyopreseyn]s %00'T Se Posy) opAyapreseinigy aL Lxaqio 9 w c€ 9 VO WO] (991 BW suorpesp onjod ayeusyd uinipos “aus sod Wp IS VY 481 = UORNIIp sip ®) Zopsoy sv jousyd %00'| pedeyoed o1jousyd WW ¢] [907 WY 1d] ‘jonorg sAep Sp opAyapyeseinys %0'0 SB pos) ~opAyopreseinio aL LOO adi w 9 1s VHO W Of (997 BW sUOTPeSIP ood “gus sod b™ 97 “4 VO $27 = UORNIP sy @) ZopsoD podeyoed Ul OZ 2900 WY [PUPP (79L sAep 87 apAyapleseynys % 07 € SB pos) opAyoppeseinicy al sn1dxagIo wg 1S YAO Ww ¢ ‘90d WV suotpssip ood “agus sod w €Z IS VY 491 = YoNNTIp sip ©) Zopsoy pose yoed UW OZ (901 YW XO sAep O€ apAyopyesein[d %07'£ SB Posy) opAyepyeseinisy al O€ S'1d AGIONLIN wT sa Vuo QUOU :992 BW § onod uonnpp sy | oyeusyd umipos%oe'O | Vuo Aq 0'H ul 9 1S VUO J€R = UONNIIP sip B) ZonsSoD JO} oft] osNas jousyd %97 "1 sped oyousyd QUuOU :90J IJPY A\dsuaqysy pareys ON opAyrprereinys %0¢°0 € Pony -apAyapyeszeinin aL tp: NIGIONWOds w | Is VO QuUOU 901 WY § nod 99° I$ vorNyTp sty oyeuayd uinipos %09'0 + | Wao 4G 0'H wy as Veo = UoNNTIp sity @) Zopso5 JO} aft] ONS jousyd %EC"€ ued o1yous4d QUOU 299s WY A\dsueqysy pores ON opAyopyeseynys %00'| 1 pani ~opAyopreseinicy a t 1 NIGIOMWOds aart asnau daisal NOLLATIG VuO Ad GaLsaL adaLv.is LV SLNAIGAYONI aaLsaL ANODALVO NOLL LV ZO/LSOO ¥ WW BALLOV LNAONAd |} NOLLA'TIG |} INVLOGANISIC aWLL ‘ANVdWOO “AWVYN GNVUE Gas 8 TTONNIIp ‘pBo] 3uUess0 “31) SUOTJNIOS UO SS9.AJS BSN-JBIUYD 10J MOTE 07 AQayes Jo UPAIBUL 10j SUBIU [[e OF SAINUTUL CT }SB9] 8 Ppy al] 2SNAsA S, UOIN[OS ay) 49A0 pauLtojsed sjsaj adyjNu Jo suBIU ae SaUy }28;U09 YY ‘SOUT PRWUWOS JOPOYS Ul }]NSeZ pjnom sompesoduua, JoySIPY “D, €7 J0J ose JoNORJNUEW Aq surrejo orjod opromueg 2 [Teg 2 “D,67 Jo} ore JoNpoRsNUEUL Aq SUUTEIO EE / XOPID ap snydxoptg = ‘SOUT, PRO popusuMUooes UIYJIM UORONpes orod "Boy ¢ 2 gy] "Soy 9 Poarooos JOU PIP WR s}onposd Joy spuoumuoses Auedwioo ueY} poyeyUDCUOD JOU SUORINIOS piss) VYD =§ popusunuoscss ueyy poyenusoUs sso -. t bU6's BI VUO Wi OQ] 290 ayy suoTpesIp ood ay sad O*H Yoo BN VYO 49 = UONNIIp sip @) ZoAsog sped WI O¢ 90s BW Vopesjop sep 17 opAyopyeseynys %0¢°9 € Panyiq] opAyoprereiniy aL bl TIVUALS ‘81 4YO's BN VUO Wi QT ‘or By suOTpeIIP ood au tod Oy Y's BM VUO aL = UORNTIP sip @) zoysop sured WI OE 902 BW peoseg shep [7 opAyopyeseynys %O¢'9 € PoInyiq opAyopyeseynyry al 1 ACIOINVA ‘LI = YS 'E BR VUO Oo WOLougW | pie suonpasp oro CG. oyeuoyd wmipos %g0'°Q | “yur sed O'Y 4b'e BAVA 717 = UoRNIIp sip ©) ZoAs0D Qo. jousyd %pp'o sued o1jousyd WO] 201 gy Ajdswoqyysy < sAep 0€ opAyopyeseynys %¢ 1° SI penqiq ~opAyoppeseynyy al 9I:I NIGIOMWOdS ‘91 ¥3'7 “Bm VYO wi OT ‘Ses YW suOTpeJIp o1og oyeusyd winipos ap sod OH] W ZL 83 VO 96 = UORNTIp sip M) zopsog se jousyd %0¢°9 ued o1jousud Wg] oer YW [WU] ‘Jono SAEP Cb opAyopreseynys %¢ 10 I panyiq -opAyepreseynyy aL Z:1.LNOadIM ‘SI bYt'l wa VYO w Z 00] JW jousydjAure suoMpesip ood -yar-d %S00'0 qu od OY Y6T BAVUO 79] = UORNTIp simpy M) Zojsog jousydyAusyd-o %¢70'0 sured o1jousyg Wi OT :9e7 By Xoo SAep OF opAyspyeseynys %0¢°9 61 Pani ~opAyoppereynyiy al 07:1 YWOdSATOO ‘bl w & -389) vuo w O] -0es UW suonpomp o1jog “agus tod W OL 2 VYAO 967 = UORNLIp sy M) Zojsog poseyoed W OT der By We SAEp 87 opAyopreseynys %%00'°7 S¥ posy) opAyppreseyny al XSYVLATD ‘el App. 168 CRA OBSERVATIONS & RECOMMENDATIONS CRA OBSERVATIONS - (1) POTENTIAL REASONS FOR DIFFERENT CLAIMS OF APPARENTLY SIMILAR PRODUCTS ~ (a) Different efficacy test methods & parameters used; (b) Different laboratory technicians with dif- ferent techniques; (c) Error within test methods; (d) Standard tests may not have been performed properly i.e. improper neutralization, improper organism challenge, no temperature control, etc.; & (e) Present registration system does not provide confirmation of disinfectant efficacy. (2) NEED FOR DISINFECTANT MONITORS - Rou- tine use of disinfectant monitors is necessary to tell clinician to discard solution when active ingre- dients have dropped to independable levels. (3) NO IDEAL DISINFECTANT - All disinfectants tested exhibited one or more characteristics that can be undesirable such as fair to poor odor, corro- sion of metal if soaked overnight, staining of skin &/or plastic instruments, special requirements for disposal, high cost, etc. Ideal disinfectant lacking in all negative characteristics does not exist. Clini- cians must determine characteristics they can & cannot tolerate. (4) EFFECTS OF WATER DILUTION - Undesirable clinical characteristics & costs are decreased by water dilution, but dilution also decreased anti- microbial activity which extended contact times significantly. (5) BENEFITS & PROBLEMS WHEN GLU- TARALDEHYDE COMBINED WITH PHENOLIC — Combination of glutaraldehyde with phenolics is attempt to take advantage of glutaraldehyde’s (6) App. 169 rapid virucidal activity & phenolic’s rapid tuber- culocidal activity. CRA tests showed concentra- tions of glutaraldehyde & phenolic are critical. Altering concentrations of either chemical can skew activity toward one organism at expense of other. REUSE LIFE CLAIMS VS. SOLUTION LEVELS - Under heavy use, solution levels can drop so low after about 2 weeks that longer reuse life claims become irrelevant. CRA RECOMMENDATIONS - Since all 18 disinfectants tested eventually destroyed both test organisms, clinical choices can be based on desired speed of disinfection, amount of tolerable active ingredients, & cost. CRA suggests following rationale for choosing product best suited to individual needs. (1) (2) (3) IF CLINICIAN NEEDS FASTEST POSSIBLE KILL OF RESISTANT ORGANISMS & COST, ODOR, & CORROSION ARE NOT CONSIDERATIONS - Sporicidin 1:2 or 1:4 are products of choice. IF CLINICIAN NEEDS FAST KILL OF RESISTANT ORGANISMS & TOLERANCE OF ORGANIC LOAD OVER TIME IS NEEDED - Metricide Plus 30 or Cidexplus 3.2% glutaraldehydes are products of choice. These higher concentration glu- taraldehydes are ideal for pre-disinfection of instruments to lower microbe counts before han- dling. CRA tests show higher glutaraldehyde con- centration maintains activity longer during heavy use & in presence of heavy bioburden. IF CLINICIAN WILL TOLERATE 45-60 MINUTE SOAK TIME INDUSTRY STANDARD IS 2% GLU- TARALDEHYDE —- There are numerous 2% glu- taraldehydes & glutaraldehyde-phenolics from which to choose (Banicide not diluted, Cidex 7, (4) App. 170 Procide, Metricide 28, Sporicidin diluted 1:8, Ster- all not diluted, & Wipe Out not diluted). For prac- tices that can tolerate soak times from 1-3 hours, 2 additional 2% glutaraldehydes (Glutarex & Omni- cide) & 2 additional glutaraldehyde-phenolics (ColdSpor diluted 1:20 & Wipe Out diluted 1:2) are possibilities. WHEN SOAK TIMES CAN EXTEND 4-6 HOURS & LOWEST. POSSIBLE CONCENTRATION OF ACTIVE INGREDIENTS IS DESIRED TO MINI- MIZE HYPERSENSITIVITY - Sporicidin diluted 1:16 & Banicide & Sterall both diluted 1:4 fill] this need. App. 171 REFERENCE NO. 18 JADA, Vol. 129, July 1998 HOW WELL DOES THE CHEMICLAVE STERILIZE HANDPIECES? ROBERT A. KOLSTAD, PH.D. ABSTRACT Using the Food and Drug Administration’s protocol for testing health care sterilizers, the author investigated the ability of chemical vapor and steam to sterilize handpieces. Five internal sites of six high-speed hand- piece models and four internal positions of one low- speed handpiece model were each inoculated with 10° Bacillus stearothermophilus spores. Half-cycle chal- lenges were conducted with Chemiclave models EC 5500 and 8000 (Barnstead/Thermolyne) and with two autoclaves, Tuttnauer 2540M (large chamber) (Tuttnauer USA Co., Ltd.) and Statim Cassette (SciCan USA). Experiments with spores either openly exposed or par- tially enclosed prove that Between-patient instrument processing — including clean- ing, packaging, loading, device operation, monitoring and storage — is a subject of continuous interest to heath care practitioners.!© So, too, is sterilization, which dental offices experience as procedure, not end effect. The prac- ticing dental community does not inspect instruments cycled through steam, heated air or chemical vapor for surviving microorganisms. The marketing of sterilization devices is regulated by the Food and Drug Administration, or FDA. In 1976, that App. 172 agency began developing an official definition of steriliz- ation, requiring manufacturers intending to market health care sterilization devices to prove efficacy claims.” The FDA published its requirements in 1993.8 In that document, the agency prescribed the boundaries of the sterilization process, incorporating two basic principles. - Overkill. After use, each instrument is assumed to be contaminated with microbes higher in both number and resistance than those actually encountered. Accordingly, efficacy studies are to be initiated with one million (108) microbes of the kind most difficult to destroy by the lethal agent in question. For example, bacterial spores could be used in a study of the effectiveness of steam or heated air. ~ Sterility assurance level. The sterility assurance level, or SAL, is the probability - by consensus considered low enough for patient safety ~ that each processed item bears a single surviving microbe. For reused health care instru- ments, the SAL is one in one million (10-2). Sterilization claims are expressed as the stress needed to achieve the prescribed viability reduction — for example, the length of time an instrument is exposed to a particular temperature. In practice, microbes on suitable carriers — such as stainless steel washers ~ are exposed to steam, heated air or another lethal agent. The sterilization claim is the time during which the population is reduced to 10 percent multiplied by 12 (the time during which viability would fall from 10° to 10-6). In turn, that rate of extrapolation must be confirmed with a test employing instruments that bear 10° microbes. The exposure time App. 173 during which total kill is achieved must not exceed half the sterilization cl [Text truncated at 120,000 characters. The full text is on the page linked above.] --- Source: Frix Law Library, https://www.frixlaw.com/law-library/documents/brief%3Amicro_IA40386018_1497%3A4. Public record. Not legal advice.