Fan pressurization measurements by four protocols.

Thirty-one independent fan pressurization measurement series were performed on seven apartments in three family housing buildings at Fort Riley, Kansas, using four protocols. The tests followed procedures in new or revised fan pressurization standards by the International Standards Organization (ISO), American Society for Testing and Materials (ASTM) and Canadian General Standards Board (CGSB). In addition, the effect of interzonal flow was considered. The three standards gave similar results. The tests during windy and calm conditions demonstrated that basic uncertainty calculations give a comparative indication of the quality of the results. The tests addressing interzonal flow did not show a strong influence on airtightness results, based on whether the adjacent units were open, closed, or pressurized at the same level.