Effects of air velocity and temperature on VOC emissions from architectural coatings

Volatile organic compound (VOC) emissions from building materials are typically tested under standardized conditions (i.e., at ~23 C and 50% RH). While a standardized testing condition is desirable to produce comparable and compatible emission data, it is also necessary to understand the effects of various environmental conditions on material emissions. Experiments were designed to quantify the effects of environmental factors including air velocity and temperature on the VOC emissions from solvent-based paint. To report the effects in a quantitative format, the varied levels of environmental factors were correlated with coefficients of a mass-transfer model accounting for internal diffusion and surface evaporation. It was observed that diffusion coefficient is a function of air temperature, while evaporation coefficient is a function of air velocity.Les \ue9missions de compos\ue9s organiques volatils (COV) provenant des mat\ue9riaux de construction sont ordinairement test\ue9es en conditions normalis\ue9es (soit, \ue0 ~23 oC et \ue0 50 % HR). Bien qu?il demeure souhaitable de disposer de telles conditions normalis\ue9es pour pouvoir obtenir des donn\ue9es \ue0 la fois comparables et compatibles sur les \ue9missions de substances, on se doit en outre de bien comprendre les incidences qu?ont diverses conditions environnementales sur ces \ue9missions. Des exp\ue9riences ont \ue9t\ue9 con\ue7ues dans le but de quantifier les effets de facteurs environnementaux tels que la vitesse de circulation de l?air et la temp\ue9rature sur les COV \ue9mis par la peinture \ue0 base de solvant. Pour faire \ue9tat de ces incidences selon un format quantitatif, on a corr\ue9l\ue9 les niveaux vari\ue9s des facteurs environnementaux avec les coefficients d?un mod\ue8le de transfert de masse repr\ue9sentant la diffusion interne et l?\ue9vaporation superficielle. Il a \ue9t\ue9 observ\ue9 que le coefficient de diffusion est fonction de la temp\ue9rature de l?air, et le coefficient d?\ue9vaporation, de la vitesse de circulation de l?air.Peer reviewed: YesNRC publication: Ye