The Asbestos Hazard Emergency Response Act (AHERA) only requires air testing following an asbestos response action (e.g., asbestos repair or removal activity) to determine whether the activity has been properly completed. This is done by measuring the amount of asbestos in the air where the asbestos response action took place, and is referred to as "clearance." However, the local education agency, e.g., the school district, may hire a qualified consultant to test its air at any time, as may be needed or appropriate.