4.1 Air quality standards for ozone have been promulgated by government authorities to protect the health and welfare of the public. Though ozone itself is a toxic material, it is often complex organic compounds that cause the symptoms of smog such as tearing and burning eyes. However, ozone is the predominant oxidant and is much more easily monitored than organic species. Since ozone concentrations are also correlated with other photochemical oxidant levels, it is the substance that is specified in air quality standards and regulations.

1.1 This test method describes the sampling and continuous analysis of the ozone content of the atmosphere at concentrations of 20 μg to 2000 μg of ozone/m³ (10 ppb (v) to 1 ppm (v)).

1.2 This test method is limited in application by its sensitivity to interferences as described below. This test method is not suitable for personal sampling because of instrument size and sensitivity to vibration and ambient temperature.

1.3 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Some specific precautionary statements are presented in Section 8.

1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.