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 Development of ISO Procedure. The ISO working group responsible for the development of ISO 15202-2, ISO/TC 146/SC 2/WG 2, began its task in September 1995, not long after the publication of the Fairfax and Blotzer article [1]. Shown in Table 2 is a list of countries that participated in voting on the technical content of the draft international standard when it was circulated for balloting, from 1996 to 2000.

TABLE 2. “PARTICIPATING MEMBER”1 COUNTRIES OF ISO/TC 146/SC 2 (DURING THE PERIOD OF DEVELOPMENT OF ISO 15202-2 [1996-2000]) ______________________________________________________________________________ Belgium Korea Turkey Germany

Netherlands

United Kingdom

India

Poland

United States

Italy

Spain

Japan

Sweden

1“Participating,”or P-Member, countries are those nations able to vote on Draft International Standards, and therefore may provide comments on the technical content of the documents during voting. “Observing,” or O-Member, nations (not listed) may also offer comments and can participate in the development of ISO standards. However, in the formal ISO voting process, O-member nations can vote only on Final Draft International Standards, which allows only for editorial, and not technical, changes at this stage.

Because of the various operational definitions for “soluble” metal compounds, a significant challenge was presented to the ISO working group responsible for the development of an international standard method to describe a procedure for extracting soluble metals and metalloids for subsequent atomic spectrometric analysis. Two choices were available based on the standard methods mentioned above: (1) extraction in pure water, or (2) extraction in 0.1 M HCL. It was decided by consensus of ISO delegates present at the earlier working group meetings to follow the former course, where solubility of metal compounds in occupational hygiene samples is defined in chemical terms. This decision was upheld during the later international voting process, which involved those countries listed in Table 2. Nevertheless, text within the International Standard [3] states that individual countries may specify alternative procedures for the measurement of soluble metal species in workplace air samples. This, then, leaves open the option to use other extraction media, such as 0.1M HCl. The ISO procedure for soluble metals and metalloids assumes that samples were collected using the new International Standard for the collection of workplace air samples for subsequent multi-element analysis, ISO 15202-1 [20]. However, the choice of filter material used for the collection of samples targeted for the “soluble” metals procedure is important. Annex A of ISO 15202-1 [20] and Annex B of ISO 15202-2 [3] provide useful guidance on this subject. The “soluble” metals procedure described in ISO 15202-2 [2] lists all of the elements in

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NIOSH Manual of Analytical Methods