At what distance should a fan typically be placed from a power source?

The placement of a fan, particularly in the context of whole-building airtightness testing, is crucial for ensuring effective airflow and accurate results. Typically, a fan should be positioned about 100 feet from a power source. This distance allows for the use of standard extension cords without compromising the fan's performance due to voltage drop, which can occur if the cords are excessively long or if inadequate gauge wire is utilized.

Setting the fan at this distance helps maintain the necessary airflow strength required for reliable testing, while ensuring that electrical safety standards are met. It strikes a balance between accessibility to power and operational efficiency of the fan, which is essential for achieving optimal indoor pressure variations during the test. The specified distance is aligned with industry practices, which emphasize both the effectiveness and safety of testing procedures.