5.1 Sources of particulate and water-soluble gaseous fluorides in the atmosphere include the fertilizers, aluminum reduction plants, phosphate processors, steel mills, coal burning operations, brick and tile manufacturers, and various less significant sources (5). Gaseous fluorides can cause adverse effects when ingested or inhaled by animals or humans, or absorbed by plants. The procedures documented in this test method provide a means of determining of particulate and water soluble gaseous fluoride in atmospheres.

5.2 This test method provides a means of separation and collection of particulate and water soluble gaseous fluoride and provides samples that are convenient to analyze.

1.1 This test method provides a procedure for separation and collection of particulate and water-soluble gaseous fluorides from the atmosphere on a chemically treated filter and in an impinger. The sampling rate may vary from 30  L/min (1.0 ft³/min) to 15 L/min (0.5 ft³/min) for longer sampling periods depending on the atmospheric fluoride concentration. This test method is not intended to be applied to gaseous fluorine compounds that are not water-soluble.

1.2 There are several limitations of the test method:

1.2.1 Although the acid-treated, medium retentive, prefilter has been shown to allow passage of HF, it restricts passage of particulate matter only as small as about 1 μm. Thus, smaller particulate matter may pass through the filter and be collected in or pass through the impingers.

1.2.2 The maximum sample volume to be taken using this test method prior to changing the acid-treated prefilter is recommended as 12 m³. This recommendation is made to minimize any effects due to particulate matter build-up.

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. For specific precautionary statements, see 7.4.3.

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.