# Ohio Admin. Code 3745-21-03: Rule 3745-21-03. Methods of ambient air quality measurement

> Ohio · Regulations · In force

URL: https://www.frixlaw.com/law-library/statutes/STATE_OH_ADC_3745_21_03

## Section

- **Citation:** Ohio Admin. Code 3745-21-03
- **Heading:** Rule 3745-21-03. Methods of ambient air quality measurement
- **Jurisdiction:** Ohio
- **Kind:** Regulations
- **Status:** In force
- **Text as of:** August 14, 2026
- **Source:** Compiled text
- **Location:** Ohio Administrative Code / Agency 3745 / Chapter 3745-21 / Rule 3745-21-03

## Text

119.03 [Comment: For dates and availability of non-regulatory government publications, publications of recognized organizations and associations, federal rules, and federal statutory provisions referenced in this rule, see paragraph (JJ) of rule 3745-21-01 of the Administrative Code titled "referenced materials."] (A) For purposes of ascertaining, defining, and measuring ambient air quality, air contaminants shall be measured by the method or methods stated in paragraphs (B) to (C) of this rule or by such other methods as may be approved by the director. (B) Concentrations of carbon monoxide in ambient air shall be determined as follows: (1) Hourly integrated concentrations of carbon monoxide shall be determined through the use of a continuous sampling and recording device as described in 40 CFR part 50, appendix C. (2) Eight hour concentrations shall be determined by arithmetically averaging the hourly integrated data, obtained as described in paragraph (B)(1) of this rule, for any eight-hour period. An eight-hour average shall be considered valid if at least seventy-five per cent of the hourly averages for the eight-hour period are available. In the event that only six (or seven) hourly averages are available, the eight-hour average shall be computed on the basis of the hours available using six (or seven) as the divisor. (C) Concentrations of ozone shall be determined through the use of a continuous sampling and recording device as described in 40 CFR part 50, appendix D. Last updated October 6, 2023 at 10:29 AM Supplemental Information Authorized By: 3704.03 (E) Amplifies: 3704.03 (A), 3704.03 (E) 11/29/2026 9/15/1970, 11/5/2002, 8/25/2008

## Nearby sections

- [Ohio Admin. Code 3745-21-01 Rule 3745-21-01. Definitions and incorporation by reference](https://www.frixlaw.com/law-library/statutes/STATE_OH_ADC_3745_21_01.md)
- [Ohio Admin. Code 3745-21-03 Rule 3745-21-03. Methods of ambient air quality measurement](https://www.frixlaw.com/law-library/statutes/STATE_OH_ADC_3745_21_03.md)
- [Ohio Admin. Code 3745-21-04 Rule 3745-21-04. Compliance time schedules](https://www.frixlaw.com/law-library/statutes/STATE_OH_ADC_3745_21_04.md)
- [Ohio Admin. Code 3745-21-06 Rule 3745-21-06. Classification of regions](https://www.frixlaw.com/law-library/statutes/STATE_OH_ADC_3745_21_06.md)
- [Ohio Admin. Code 3745-21-07 Rule 3745-21-07. Control of emissions of organic materials from stationary sources (i.e., emissions that are not regulated by rule 3745-21-09, 3745-21-12 to 3745-21-16, or 3745-21-18 to 3745-21-29 of the Administrative Code)](https://www.frixlaw.com/law-library/statutes/STATE_OH_ADC_3745_21_07.md)
- [Ohio Admin. Code 3745-21-08 Rule 3745-21-08. Control of carbon monoxide emissions from stationary sources](https://www.frixlaw.com/law-library/statutes/STATE_OH_ADC_3745_21_08.md)
- [Ohio Admin. Code 3745-21-09 Rule 3745-21-09. Control of emissions of volatile organic compounds from stationary sources and perchloroethylene from dry cleaning facilities](https://www.frixlaw.com/law-library/statutes/STATE_OH_ADC_3745_21_09.md)
- [Ohio Admin. Code 3745-21-10 Rule 3745-21-10. Compliance test methods and procedures](https://www.frixlaw.com/law-library/statutes/STATE_OH_ADC_3745_21_10.md)
- [Ohio Admin. Code 3745-21-11 Rule 3745-21-11. Reasonably available control technology studies for non-CTG sources in ozone nonattainment areas](https://www.frixlaw.com/law-library/statutes/STATE_OH_ADC_3745_21_11.md)
- [Ohio Admin. Code 3745-21-12 Rule 3745-21-12. Control of volatile organic compound emissions from commercial bakery oven facilities](https://www.frixlaw.com/law-library/statutes/STATE_OH_ADC_3745_21_12.md)
- [Ohio Admin. Code 3745-21-13 Rule 3745-21-13. Control of volatile organic compound emissions from reactors and distillation units employed in SOCMI chemical production](https://www.frixlaw.com/law-library/statutes/STATE_OH_ADC_3745_21_13.md)
- [Ohio Admin. Code 3745-21-14 Rule 3745-21-14. Control of volatile organic compound emissions from process vents in batch operations](https://www.frixlaw.com/law-library/statutes/STATE_OH_ADC_3745_21_14.md)
- [Ohio Admin. Code 3745-21-15 Rule 3745-21-15. Control of volatile organic compound emissions from wood furniture manufacturing operations](https://www.frixlaw.com/law-library/statutes/STATE_OH_ADC_3745_21_15.md)
- [Ohio Admin. Code 3745-21-16 Rule 3745-21-16. Control of volatile organic compound emissions from industrial wastewater](https://www.frixlaw.com/law-library/statutes/STATE_OH_ADC_3745_21_16.md)

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Source: Frix Law Library, https://www.frixlaw.com/law-library/statutes/STATE_OH_ADC_3745_21_03. Check the current official text before relying on it. Not legal advice.