Microcomputer-based system for real-time computation of time-weighted average levels of ethylene oxide and other gases.

Accurate measurement of the time-weighted average of ethylene oxide levels down to the 1 part per million level, as mandated by OSHA, requires great attention to technique and the methods used to compute the time-weighted average. A microprocessor-based instrument that provides real-time computation and display of the time-weighted average of this or other gas levels, when used in conjunction with an analytic instrument, such as an infrared spectrophotometer, was built. The instrument provides greater accuracy than that attained with manual data collection methods, while eliminating time-consuming off-line manual computations. An overview of conventional methods, as well as a description of the new device, is presented.