Vaporizing characteristics of mixed-solvents in indoor environment

Vapor pressure is usually used for predicting the phase-transfer of solvent. Combining it with molar ratio of component in liquid phase, airborne concentration of solvent is theoretically calculated. It's worthwhile to clarify if it is true in real environment. This study examines the vaporizing profile of xylol (commercial xylene) manipulation in a paint-manufacturing plant. Twelve workers equipped with 3M 3500 passive organic vapor monitors were sampled for 3 days. Solvents were analyzed by a gas chromatograph with flame ionization detector. According to the results, concentration ratio of airborne ethylbenzene and xylene is 0.384, though the ratio is 1.0 in the liquid phase and both solvents have similar vapor pressures. This finding suggests that predicting solvent's airborne concentration by liquid composition and vapor pressure may distort the air pollution profile. Moreover, high temperature increased airborne concentration significantly.