1.1 This guide provides quantitative and qualitative tools for evaluation of indoor air quality (IAQ) models. These tools include methods for assessing overall model performance as well as identifying specific areas of deficiency. Guidance is also provided in choosing data sets for model evaluation and in applying and interpreting the evaluation tools. The focus of the guide is on end results (that is, the accuracy of indoor concentrations predicted by a model), rather than operational details such as the ease of model implementation or the time required for model calculations to be performed.

1.2 Although IAQ models have been used for some time, there is little guidance in the technical literature on the evaluation of such models. Evaluation principles and tools in this guide are drawn from past efforts related to outdoor air quality or meteorological models, which have objectives similar to those for IAQ models and a history of evaluation literature (1).2 Some limited experience exists in the use of these tools for evaluation of IAQ models.

1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Rec