5.1 Airborne hexavalent chromium is carcinogenic (1),⁴ and analytical methods for the measurement of this species in workplace aerosols are desired. Worker exposure to hexavalent chromium occurs primarily through inhalation (1), and this test method provides a means for exposure assessment to this highly toxic species. Analytical results from this procedure can be used for regulatory compliance purposes (2).

1.1 This test method specifies a method for the determination of the time-weighted average mass concentration of hexavalent chromium in workplace air samples.

1.2 The method is applicable to the personal sampling of the inhalable fraction of airborne particles, as defined in ISO 7708, and to area (static) sampling.

1.3 The sample dissolution procedure specifies separate procedures for soluble and insoluble hexavalent chromium.

1.4 The method is applicable to the determination of masses of 0.01 μg to 10 μg of hexavalent chromium per sample without dilution.

1.5 The concentration range for hexavalent chromium in air for which this procedure is applicable is approximately 0.1 μg/m ³ to 100 μg/m³, assuming 1 m³ of air sample. The range can be extended upwards by appropriate dilution.

1.6 Interconversion of trivalent and hexavalent chromium species may occur during sampling and sample preparation, but these processes are minimized to the extent possible by the sampling and sample preparation procedures employed.

1.7 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.8 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 and health practices and determine the applicability of regulatory limitations prior to use.