General view of an unidentified female technician inserting a sample of an organic solvent into a Perkin-Elmer gas chromatograph at a laboratory associated with the National Institute for Occupational Safety and Health (NIOSH). Per notations accompanying the photograph, the gas chromatograph is linked to a Perkin-Elmer Processor (PEP) system that provides pre-programmed computer analyses of the components of complex mixtures. In the foreground, government chemists from Spain are seen being briefed on the laboratory's method by a NIOSH chemist.