Behaviour of individual VOCs in indoor environments: How ventilation affects emission from materials

Abstract

Indoor air quality is affected by both emissions of Volatile Organic Compounds (VOC) from materials and ventilation. The purpose of this paper is to provide a multi-scale analysis of the impact of ventilation on VOC emissions to highlight the individual behaviours of VOCs emitted from a wood particleboard. Emissions were studied in an experimental chamber by (i) assessing the effect of ventilation on emission rates and (ii) determining intrinsic parameters (Ki, C0,i, Di) describing the VOC mass transfer from the material to air. The overall assessment of the effect of ventilation indicated that the air change rate could significantly affect the behaviour of individual compounds. Typically, the formaldehyde emission rate increased from 214.6 to 274.2 μg.m−2.h−1 when air change rate varies from 2.5 to 5.5 h−1, whereas the air speed had no influence on emission rates for any VOC monitored. These results agree with the key emission parameters (partitioning and diffusion coefficients) which were higher for formaldehyde than those for other compounds. VOC diffusion related to VOC mass transfer from a material's surface to the surrounding air was the limiting step in VOC emission for the solid material studied, and should therefore be considered when developing ventilation strategies.