1- (https://www.osha.gov/SLTC/index.html (OSHA
2- https://www.ehs.ucla.edu) (Safety, Health, and Environment Office at the University of California)
3- (http://www2.epa.gov/science-and-technology/land-waste-and-cleanup-scien… (United States Environmental Protection Agency)
4- http://www.998.gov.sa/Ar/Safety/Pages/default.aspx Safety Regualtions of the Fire Department