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This paper describes the evaluation of a new personal sampler for organic vapors which is totally different from traditional sampling techniques using pumps and adsorption tubes. Sampling of organic vapors is effected by collection on an adsorption substrate contained within a small passive sampler worn by the worker. The collection element is removed from the sampler and subsequently analyzed for organic vapors. The results are equated with the time-weighted-average concentration of contaminants in air. This new sampling device circumvents inherent errors generally associated with sampling pumps and tubes; e.g., changes in pumping rates and variable pressure drops across adsorption tubes. Applications of the sampler were demonstrated on various concentrations of benzene, methyl isobutyl ketone, isooctane, butyl acetate, methyl chloroform, trichloroethylene, butanol and solvent mixtures. Variables studied included the effects of temperature, charcoal lot, and air velocities. In addition, the occurrence of "breakthrough" and effect of time on sample stability were investigated.

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New findings from animal studies indicate that there is a serious cancer risk associated with exposures to hydrazines. In June, 1978, NIOSH announced more restrictive occupational exposure levels for these compounds. Adherence to these limits requires improved analytical methodology. This paper describes a modified method for monitoring hydrazine and unsymmetrical dimethylhydrazine in atmospheric samples below the ceiling concentrations recommended by NIOSH. The method utilizes a GC concentrator for which a "trap" (ventable GC precolumn) was prepared and tested. Using this trap, up to 40 microL sample injections (injections much too large for conventional GC work) are effectively chromatographed. Presented are data on the overall efficiency of the method for airborne hydrazine and unsymmetrical dimethylhydrazine in the concentration ranges of 0.02 - 0.67 mg/m3 and 0.04 - 1.04 mg/m3, respectively.