A UV-conductivity method for determination of airborne levels of vinyl chloride

A method has been developed for the measurement of vinyl chloride based on the decomposition of vinyl chloride and the subsequent measurement of the conductivity of these materials in deionized water. Air containing vinyl chloride is sampled through a glass flask containing an ultraviolet lamp. The sample rate for efficient conversion of the vinyl chloride to conductive materials is 2 liters per minute. The wavelength of the ultraviolet light emitted by the six-inch lamp is 2537 Angstroms. Ninety-two percent of the ultraviolet light emitted by the lamp is at this wavelength. The sampled air is then drawn through deionized water, the decomposition products are absorbed and the resulting conductivity measured. Vinyl chloride concentrations of less than one-tenth of a part per million can be detected by the method.