The measurement and monitoring of volatile organic

0,49

MB

compounds to air from industrial installations

56

stron

6570

ID

Environment Agency

2005

rok

Contents

1. Background - Volatile Organic Compounds (VOCs): Definitions and Environmental Impacts 1

1.1 The Definitions of a VOC. 1

1.2 A summary of the environmental impacts of VOCs . 2

1.3 The Environment Agency’s considerations and requirements 2

1.4 The Formation of photochemical ozone 2

1.5 Effects on human health 3

1.6 Stratospheric ozone depletion . 3

1.7 Odour 3

1.8 Effects on plant life . 3

2. Major stationary sources of VOC emissions. 3

2.1 Human sources of VOCs. 3

2.2 Natural sources of VOCs 4

3. Types of VOCs. 4

3.1 Classification of VOCs . 4

4. Regulatory requirements for different processes. 6

4.1 The three ways of specifying the concentrations of VOCs . 6

4.2 Applicable legislation 6

4.3 Requirements for standards and methods for monitoring . 7

4.4 The Environment Agency’s Monitoring and Certification Scheme (MCERTS) 9

5. Techniques for monitoring VOCs 9

5.1 Common factors in monitoring - sampling and analysis regimes . 9

5.2 Non-specific detectors based on ionisation and oxidation 10

5.3 Spectroscopic methods - specific detectors. 14

5.4 Separation by gas chromatography . 16

6. Sampling and extraction systems. 17

6.1 Maintaining the integrity of the sample 17

6.2 Discontinuous and on-line systems . 17

6.3 The three types of system for discontinuous sampling . 18

7. Frameworks, standards and methods for monitoring . 20

7.1 Total VOCs . 20

7.2 Specific VOCs - BS EN13649 Stationary Source Emissions - Determination of the Mass

Concentration of Individual Gaseous Organic Compounds 24

7.3 Sampling and analytical methods used for occupational health monitoring 27

7.4 USEPA Methods . 27

7.5 EPA Method 18. Measurement of Gaseous Organic Compound Emissions by Gas

Chromatography:. 33

7.6 USEPA Method 21 - Fugitive emissions 37

7.7 Iso-cyanates. 37

References 40

Appendix 1: Glossary of terms and abbreviations . 42

Appendix 2: Toxic VOCs 43

Appendix 3 - Example of calculating total organic carbon . 44

A3.1 Converting ppm to mg.m-3 44

A3.2 Calculating VOC concentrations in exhaust gases of known compositions and known response

factors. 44

A3.3 Calculating a composite response factor. 45

A3.4 Examples. 45

Appendix 4 - Response factors, and expressing TOC results as toluene equivalents. 47

A4.1 Expressing TOC data as toluene, and deriving response factors 47

A4.2 Response factors . 47

A4.3 The theoretical response relating methane to toluene . 48