OSHA stands for Occupational Safety and Health Administration... it's pretty much an organization dedicated to make safe working and living environments in construction/living areas, like the way you properly use a tool is stated by OSHA as well as how construction workers such as carpenters, plumbers and electricians are supposed to do their work so that it's safe when people move into the home that is built or work in the buildings that they built.. I hope it helps, I know it's a bit difficult at first *studied to be an electrician*