Development of a solid sorbent monitoring method for chlorine and bromine in air with determination by ion chromatography.
Appl Occup Environ Hyg 1991 Mar; 6(3):215-226
A method was developed for the analysis of chlorine (7782505) and bromine (7726956) in air, based on the reaction of halogen gases with silver to form silver halides in a solid sorbent sampling system. An opaque, 25 millimeter cassette containing a Zefluor or polyester prefilter and a cleaned silver membrane filter was used in the sampler. Thiosulfate complexed with the silver halides, released the halide ion which was subsequently determined by ion chromatography. Generated test atmospheres were used to evaluate the method in the laboratory. Field testing was conducted at a chlorine containing industrial environment. The method had a precision of 7.2% and the bias was insignificant. The capacity of the silver for chlorine and bromine was dramatically increased by high humidity. A minor positive interference was generated by hydrogen-chloride. The author states that the method can monitor chlorine concentrations as low as 0.5 part per million (ppm), which is the current OSHA time weighted average (TWA), and can measure short term exposure limits (STELs) of 1ppm for chlorine. Bromine can be monitored at 0.1ppm TWA and at an STEL of 0.3ppm. The silver filter used in this study has the potential for use in monitoring other toxic gases and vapors such as iodine (7553562), fluorine (7782414), and hydrogen-sulfide (7783064).
NIOSH-Author; Analytical-methods; Chemical-analysis; Analytical-chemistry; Air-quality-monitoring; Chemical-manufacturing-industry; Sampling-methods; Halogenated-hydrocarbons; Sampling-equipment
7782-50-5; 7726-95-6; 7553-56-2; 7782-41-4; 7783-06-4
Applied Occupational and Environmental Hygiene