ASTM D7439-08

The health of workers in many industries is at risk through exposure by inhalation to toxic metals and metalloids. Industrial hygienists and other public health professionals need to determine the effectiveness of measures taken to control workplace exposure. This is generally achieved by making workplace air measurements. This test method has been developed to make available a standard methodology for valid exposure measurements for a wide range of metals and metalloids that are used in industry. It will be of benefit to agencies concerned with health and safety at work; analytical laboratories; industrial hygienists and other public health professionals; industrial users of metals and metalloids and their workers; and other groups.

This standard test method specifies a generic method for determination of the concentration of metals and metalloids in workplace air samples using ICP-MS. For many metals and metalloids, analysis by ICP-MS may be advantageous, when compared to methods such as ICP atomic emission spectrometry, due to its sensitivity and the presence of fewer spectral interferences.

The analysis results can be used for the assessment of workplace exposures to metals and metalloids in workplace air.

1.1 This standard test method specifies a procedure for sample preparation and analysis of airborne particulate matter for the content of metals and metalloids in workplace air samples using inductively coupled plasma–mass spectrometry (ICP-MS).

1.2 This standard test method assumes that samples will have been collected in accordance with Test Method D 7035.

1.3 This standard test method should be used by analysts experienced in the use of ICP-MS, the interpretation of spectral and matrix interferences and procedures for their correction.

1.4 This standard test method specifies a number of alternative methods for preparing test solutions from samples of airborne particulate matter. One of the specified sample preparation methods is applicable to the measurement of soluble metal or metalloid compounds. Other specified methods are applicable to the measurement of total metals and metalloids.

1.5 It is the user's responsibility to ensure the validity of the standard method for filters of untested matrices.

1.6 Table 1 provides a non-exclusive list of metals and metalloids for which one or more of the sample dissolution methods specified in this document is applicable.

1.7 This standard test method is not applicable to compounds of metals and metalloids that are present in the gaseous or vapor state.

1.8 No detailed operating instructions are provided because of differences among various makes and models of suitable ICP-MS instruments. Instead, the analyst shall follow the instructions provided by the manufacturer of the particular instrument. This test method does not address comparative accuracy of different devices or the precision between instruments of the same make and model.

1.9 The values stated in SI units are to be regarded as standard.

1.10 This standard test method contains notes that are explanatory and are not part of the mandatory requirements of the method.

1.11 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.