The ASTM Standard Guide for Small-Scale Environmental Chamber Determinations of Organic Emissions from Indoor Materials/Products (ASTM D 5116) was first published in 1990 and is due for review and revision in 1995. Since its publication, we have gained a substantial amount of information about emissions processes that may affect the implementation of the test method. The upcoming revision will be an opportunity to incorporate that information. This paper addresses several issues that should be considered in the revision.
The effect of air velocity on emissions was demonstrated by testing a constant evaporative source. When the air velocity increased from <3 to 46 cm/s, the emission rate increased by a factor of three. Given the importance of this parameter, its measurement should be standardized.
A wood finishing product was applied to the substrate with different sizes and tested in small chambers. When the size of the test specimen was reduced from 221 to 12 cm2, the mass transfer coefficient increased by a factor of three, suggesting that the “edge effect” can be an important factor affecting the rate of emissions from test specimens.
ASTM D 5116 should enhance its discussions on emission factor estimation to include a wider range of models and different methods by which the model parameters are determined. Computer simulations showed that, when indoor coating materials are tested in chambers, loss of volatile components from the source during sample preparation can cause errors in emission factor estimates.