Estimating Air/Contaminant Transport Rate and Time From Attached Garages to Residential Living Spaces With a Single Tracer Gas Decay Test

To characterize the air and contaminant transport from an attached garage to a living space in a multizone residential building, a novel mathematical regression model is proposed in this paper to estimate the transport rate and time and interpret the measurement results from a single tracer gas decay test. Unlike conventional contaminant/tracer gas experimental methods, which only characterize air/contaminant transport by comparing the average or highest concentrations of contaminant/tracer gas measured in the release zone and the target zone, this proposed model establishes a mathematical relationship directly between the two tracer gas concentrations, with the air transport rate and time factored into the coefficients of the model equations. Thus, the air/contaminant transport rate can be explicitly and empirically estimated from the data of the tracer gas concentrations measured during a simple tracer gas decay test without extra experimental requirements. The effectiveness of the model is verified with a few application examples showing its goodness of fit to the measured data from tracer gas decay tests in several occupied residential buildings. The proposed method can be practically used to estimate the air/contaminant transport rates and overall transport time from a single source zone to each target zone in a multizone building when all the underlying interzonal airflows are relatively constant and have minimal disturbances.