Occupational Safety and Health Administration (OSHA) 04
Occupational Safety and Health Administration (OSHA) 04 : An agency of the Department of Labor active in eliminating occupational hazards and promoting employee health and safety
United States Mine Rescue Association USMRA (membership,mine rescue and safety training resources, and mine disasters and accidents), Mine Safety and Health Quizzes, Glossary of Blasting Terms, PA,USA 2016. http: //miningquiz.com/pdf/Glossaries/Glossary_of_Blasti ng_Terms.pdf, (Blasting - Amer) {997}