NY-14-C006 -- Testing and Evaluation of Filter Media Performance: Correlation Between High and Low Challenge Concentration Tests for Toluene and Formaldehyde (ASHRAE 1557)

Experiments were carried out at both high concentrations (100 ppm [380 mg/m3] for toluene and 1 ppm [1.2 mg/m3] for formaldehyde) and low concentrations (0.05 ppm for toluene [0.19 mg/m3] and formaldehyde [0.06 mg/m3]) for five selected filtration media. The results show that 1) the high concentration test data were able to differentiate the relative performance among the media at the low concentration properly, confirming the validity of using ASHRAE 145.1 for a relative performance comparison among filter media; 2) significant initial breakthrough observed at high concentration test of large pellet media was not present at the low concentration tests, indicating the dependency of the adsorption capability of the sorbent media on the concentration level as well as the possible "by-pass" effects (i.e., not all the VOC molecules in the air stream had the same chance to be in contact with the sorbent media); 3) a mechanistic model is necessary to predict the media performance at low concentration levels based on the high concentration test result.