The support of Analytical Research Laboratories to NIOSH in performing organic chemical analyses for the NIOSH inhouse analytical group is summarized in a final report. The major work was gas chromatographic analyses of personal sampler sorbent tubes (usually charcoal) exposed to various noxious organic vapors. Some bulk materials were also submitted for analysis. A total of 16 individual jobs was requested. From these, a total of 1279 solvents, anesthetics and one resin were analyzed. Typical jobs included monitoring and sampling the air in a specified workplace with subsequent GC analysis. Quality control of analytical data has been maintained throughout the project by a three phase program. Problems in statistical analysis of quality control data are noted.