Monitoring for airborne inorganic acids.
Chemical Hazards in the Workplace, Measurement and Control, ACS Symp Ser 1981; :137-152
The use of sorbent tube samplers and ion chromatography as an analytical tool for monitoring airborne inorganic acids was evaluated. Five organic acids were used: phosphoric-acid (7664382), bromic-acid (7789313), nitric-acid (7697372), hydrochloric-acid (7647010), and sulfuric-acid (7664939). Collection tubes were made from glass tubing approximately 13 centimeters in length, packed with silica gel. Sampling was performed at a nominal flow of 0.2 liter per minute. Actual flow rates averaged 0.17 liter per minute with the sample in the line. Samples were desorbed and prepared. Samples and standards were injected into the ion chromatograph in 100 microliter aliquots. The ions were separated in the anion separator column. The mesh size and flow rate of the silica gel column were varied. The mean recovery rate for phosphoric-acid was 99.1 percent, bromic-acid was 102 percent, nitric-acid was 102 percent, and sulfuric-acid was 97.6 percent. The silica gel with the larger mesh size was a better collector of acid mists than the smaller mesh. Higher flow velocities resulted in better sample collection. Silica gel was found to be a better collector of the vapor forming acids than were impingers or bubblers. The authors conclude that sorbent tubes are viable samples for ion chromatography analysis of airborne inorganic acids.
Air-sampling; Industrial-hazards; Workers; Chemical-processing; Air-monitoring; Monitoring-systems; Hazards; Chemical-analysis; Workplace-studies; Monitors
7664-38-2; 7789-31-3; 7697-37-2; 7647-01-0; 7664-93-9
Chemical Hazards in the Workplace, Measurement and Control, ACS Symposium Series No. 149