DC-2771 -- Dynamic Method for Evaluating Room-Size Air Purifiers PDF

A dynamic chamber method for measuring the smoke, hydrocarbon gas removal, and ordorant emission rate of small ($35-$100) air purifiers has been developed and applied to the evaluation of six different purifiers. The method uses non-steady-state analysis of measurements made with a smoke photometer or a hydrocarbon analyzer to determine the efficiency-volume product, nQ_r, of the purifier if it removes smokes or gases, or its emission rate if it emits gases rather than removing them.

From theory it is estimated that a purifier should have an nQ_r > 35 cfm (1 m³/min) to be effective. The purifiers tested had an nQ_r much less than that.

Emission rates of odorants were found to decrease exponentially with time. The emission rate, S, of all of the purifiers had decreased to below 4.4 x 10^–8 lb/min (0.02 mg/min) in 12 days and most of them within about 5 days.

These experiments indicate that the dynamic chamber method is a simple and practical method for evaluating room-size air purifiers.