A continuous emissions monitoring system for continuously monitoring and evaluating air flow samples from a plurality of emission sites. The monitoring system includes a microprocessor controlled Fourier transform infrared scanning laser system for identifying and quantifying compounds in the air flow samples based on known spectral absorption bands. The monitoring system also includes an auxiliary gas chromatograph for separating and analyzing compounds belonging to a common family which exhibit interference patterns or overlapping spectral bands. The auxiliary gas chromatograph is employed in cases where the infrared scanning laser system detects high levels of compounds, above a predetermined threshold level, exhibiting such interference patterns, or when an unknown compound is detected by the infrared scanning laser system. A sampling station continuously and simultaneously draws air flow samples from the plurality of emission sites, such that an air flow sample from any of the plurality of emission sites is immediately available for analysis.

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