Validation of the indoor environmental quality conceptual model

The Indoor Environmental Quality (IEQ) conceptual model is validated with an independent consultant generated database that was not used for its formulation. The model uses the Indoor Environmental Index (IEI) to assess the IEQ and select among three management options. IEI values are either calculated using measured environmental variables or predicted by a simple linear regression model with the Percent of Occupants with Two or More Persistent Symptoms (POPS2) index as the independent variable. Responses to a questionnaire determine POPS2 values. The paper investigates if the predicted IEI values lead to the same IEQ management decisions as the expensive calculated IEI values. The null hypothesis is that there is no difference between predicted and calculated IEI values. The second objective examines the consultant effect on environmental stressor and IEI measurements by testing the null hypothesis of no difference among consultants. The difference between the calculated and predicted IEI values is not statistically significant and the inexpensive predicted values can be used for management purposes. The consultant effect on IEI values is statistically significant but interpreted to have no practical importance because it does not affect selection of management options. Consequently, it is argued that the conceptual model can be used as a proactive management tool that may be used to improve and maintain IEQ.