The National Institute for Occupational Safety and Health is a federal agency. It conducts research on health and safety concerns, tests and certifies respirators, and trains occupational health and safety professionals
US Department of Labor, Occupational Safety & Health Administration (OSHA), OSHA Office of Training and Education, Glossary of Terms, Construction Safety and Health Outreach Program, DC, USA 1996. http://www.osha.gov/doc/outreachtraining/htmlfiles /hazglos.html, Washington, (OSH - Amer) {516}