INTERLABORATORY STUDY OF A TEST METHOD MEASURING TOTAL VOLATILE ORGANIC-COMPOUND CONTENT OF CONSUMER PRODUCTS

Consumer products are potentially significant sources of volatile orga nic compounds (VOCs), which are precursors to the formation of ozone i n photochemical smog. To address the problem of ozone formation in amb ient air, the U.S. Environmental Protection Agency (EPA) has been invo lved in the development of test methods for measuring the VOC content of consumer products. This paper describes results of an interlaborato ry study to estimate the repeatability (precision of analyses performe d by a single laboratory) and reproducibility (precision of analyses p erformed by different laboratories) of the consumer products' VOC meas urement method based on EPA Method 24 (for VOCs in surface coatings). The mean method repeatability was 2.7 wt % VOC, and the mean method re producibility was 4.8 wt % VOC. Method repeatability ranged from 0.2 t o 4.4 wt % VOC, and reproducibility ranged from 0.6 to 11.9 weight per cent VOC. The precision of the VOC method for consumer products is sim ilar to the precision of EPA Method 24 for surface coatings.