The multizone airflow simulation program COMIS was evaluated within an International Energy Agency research program. One of the steps in the evaluation procedure is to test the user-code interface, consisting not only in the appearance of the computer screen, but also in the user guide or any other tutorial or help system. The user-code interface of COMIS was then tested through round robin tests. Two types of problems were submitted to several users: a simple and well-defined problem and a real world problem. This study first allowed great improvements of the user guide.

In the IEA-ECBCS Annex 23 'Multizone Air Flow Modelling,' a sensitivity analysis procedure, that included both the Monte Carlo and Fractional Factorial analyses, was defined to evaluate COMVEN, a multizone air flow code. This procedure is here applied to evaluate COMVEN, when the simulation of the ventilation of a detached house is performed for the case of ventilation driven mainly by stack effect.

A summary of the evaluation of an air flow and contaminant model as part of the IEA-ECBCS Annex 23; Mullizone Airflow Modelling' is presented. Evaluation rather validation, is the goal. The most important points of the cases analyzed during this project are presented and commented from the point of view of analytical evaluation, comparison with experimental data and user sensitivity. The conclusion addresses the need for user-friendly tools and guidelines for the analysis of simulation output

This report is from a study of the performance of eight exhaust systems of a large medical center in Tennessee. The mechanical contractor of the project initiated this study when confronted with a claim of unacceptable deficiencies in all building exhaust systems. These systems were reportedly exhausting 32% to 43% less than design airflow as a consequence of excessive leakage in the duct system.

The age of the air in a room is normally determined either from a pulse response or from a step change response (up or down). There are a certain number of problems involved in applying these two theoretical models, especially those associated with the duration of the injection, which must either be infinitely short or infinitely long. A hybrid method that consists of injecting a known quantity of tracer for a given time offers the advantages of both methods.

For more than 1 year, indoor and outdoor O3, NO, N02 (NOx - NO), temperature, and relative humidity as well as the air exchange rate have been measured continuously at a commercial building in Burbank, CA. The indoor concentration of a given pollutant is a function of its outdoor level, the air exchange rate, the rate at which it is removed by indoor surfaces, and the rate at which it is produced or removed by indoor chemistry. Several examples of indoor chemistry are inferred from daily and seasonal variations in the collected data.