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An inexpensive test chamber has been constructed that provides an environment appropriate for testing the effects of temperature and chemical interactions on gaseous emissions from test solutions. Temperature, relative humidity, and ventilation rate can be controlled and a well-mixed atmosphere can be maintained. The system is relatively simple and relies on heated tap water or ice to adjust the temperature. Temperatures ranging from 9 to 21 degrees C have been maintained. At an average temperature of 15.1 degrees C, temperatures at any location within the chamber vary by no more than 0.5 degree C, and the temperature of the test solution within the chamber varies by no more than 0.1 degree C. The temperatures within the chamber are stable enough to generate precise steady-state concentrations. The wind velocities within the chamber are reproducible from run to run. Consequently, the effect of velocity on the rate of evaporation of a test chemical is expected to be uniform from run to run. Steady-state concentrations can be attained in less than 1 hour at an air exchange rate of about 5 per hour.

A solid sorbent sampling tube packed with Tenax-GC is used with a personal sampling pump to collect samples of white (yellow) phosphorus vapor from air. The phosphorus is leached from the exposed sorbent into xylene and quantitated by gas chromatographic analysis. The capacity of the sorbents is in the range 10 to 20 microgramP4per100 mg of sorbent, which allows for up to 4 hrs of sampling at the OSHA Standard, 0.1 mg/m3. No interferences from red phosphorus, phosphine, water vapor, or other common gases are significant. The effects on the method of variations in temperature, pressure, humidity, sample storage and shipping conditions, and chromatographic parameters were determined.