Page:NIOSH Manual of Analytical Methods - Chapter A.pdf/3

3. INDEXES

There are three indexes in the back of the Manual which can be used in locating methods:

1. Fourth Edition Methods - An index of current NIOSH methods in order of Method number (pp. A-11 through A-16). [NOTE: The fourth edition uses the same numbering system as the third edition. This Index also lists the disposition of all third edition methods.
2. First and Second Edition Method Numbers - An index of the first and second edition "P&CAM" and "S" methods, from which many of the current methods were derived. This index shows the disposition of all of these methods, whether or not they were revised into current methods (pp. A-17 through A-30).
3. Names and Synonyms - An alphabetical listing of all chemical names and synonyms used in the current methods, including Chemical Abstracts Service numbers ("yellow pages," pp. A-31 through A-62).

4. METHOD FORMAT

The methods consist of three major parts:

1. Front page The first page of each method concisely summarizes sampling and measurement parameters, and gives estimates of limit of detection, working range, overall and measurement precision, and interferences. References to other methods are given. New to the fourth edition are: Method Classification, NIOSH Registry of Toxic Effects of Chemical Substances (RTECS) number, and an estimate of method Accuracy. (See Figure 1)
2. Instructions The second page of each method begins with lists of required REAGENTS and EQUIPMENT. Please note that these reflect the conditions under which the methods were evaluated, and that there may be some latitude for variation. Commercial versions of the samplers may differ slightly from the methods. The user of the methods is responsible for assuring accuracy of the results (e.g., to determine that breakthrough and recovery are acceptable for each lot of samplers used). Typical tolerances are:
   • Glass tubing used to contain solid sorbents: inside diameter is usually not critical within the range 4 to 6 mm; length should be sufficient to contain the specified mass of sorbent.
   • Contents of sorbent tubes: mass of sorbent within ±10% of specification; separators of either glass wool or cleaned polyurethane foam unless otherwise indicated, sorbent mesh size of 20/40 unless sampling efficiency dictates otherwise. Filled sorbent tubes should be sealed to protect from contamination.