The U.S. OSHA Hazardous Waste Operations and Emergency Response, HAZWOPER regulation, 29 CFR 1910.120, regulates the safety and health of the employees involved in clean-up operations at uncontrolled hazardous waste sites, employees engaged in certain hazardous waste sites, employees engaged in certain hazardous waste treatment, storage, and disposal (TSD) operations, and in any emergency response activities involving hazardous substances. In short, HAZWOPER applies to hazardous waste facilities. The HAZWOPER regulation became effective on March 6, 1990.