Association between the emission rate and temperature for chemical pollutants in building materials: general correlation and understanding.

The emission rate is considered to be a good indicator of the emission characteristics of formaldehyde and volatile organic compounds (VOCs) from building materials. In contrast to the traditional approach that focused on an experimental study, this paper uses a theoretical approach to derive a new correlation to characterize the relationship between the emission rate and temperature for formaldehyde emission. This correlation shows that the logarithm of the emission rate by a power of 0.25 of the temperature is linearly related to the reciprocal of the temperature. Experimental data from the literature were used to validate the derived correlation. The good agreement between the correlation and experimental results demonstrates its reliability and effectiveness. Using the derived correlation, the emission rate at temperatures other than the test condition can be obtained, greatly facilitating engineering applications. Further analysis indicates that the temperature-related emission rate of other scenarios, i.e., the standard emission reference and semi-volatile organic compounds (SVOCs), also conforms to the same correlation as that of formaldehyde. The molecular dynamics theory is introduced to preliminarily understand this phenomenon. Our new correlation should prove useful for estimating the emission characteristics of chemicals from materials that are subject to changes in temperature.