Abstract: At approximately 4:20 p.m. on August 9, 2011, Employee #1 was working for Realm Catalyst, Inc., and Employee #2 was working for Rainbow of Hope, aka Rainbow of Hope Foundation. Employee #1 and Employee #2 were preparing equipment for an upcoming sales demonstration for Strategic Sciences, Inc., to promote the benefits and properties of the experimental gas fuel "TyLar," which Strategic Sciences manufactured. The incident occurred in a building within an industrial park in Sylmar, CA. A pressure vessel containing compressed gases, including oxygen and hydrogen, exploded. The cylinder containing the blend of gases, known as TyLar, exploded while being handled in a work area without ignition controls. The two employees sustained severe burns and serious multiple amputations. Employee #1 was taken to Providence Holy Cross in Mission Hills, CA, where he was treated for multiple traumas, including postrespiratory failure, the above-knee amputation of his right leg, the below-elbow amputation of his right arm, superficial burns to 30 percent of his body, damage to his left medial collateral ligament, and deep venous thrombosis in his right superficial femoral vein. Employee #2 initially was taken to Henry Mayo Newhall Memorial Hospital in Valencia, CA, where he was treated for multiple traumas, including the below-elbow amputation of his left arm, second- and third-degree burns to 60 percent of his body, respiratory failure, fractures, and soft tissue injuries. To continue with his treatment, Employee #2 was transported to the Los Angeles County+USC Medical Center, in Los Angeles, CA, and later to the Rancho Los Amigos National Rehabilitation Center, in Downey, CA. The Division initiated an inspection in the evening of August 9, 2011, in response to a radio broadcast about the incident. Cal/OSHA concluded that flammable levels of TyLar gas, handled in nonexplosionproof environments, were directly contributory to the explosion. Regulatory, general, and serious citations were issued to the three companies mentioned above, and willful serious citations, in addition to those citations, were issued to Realm Catalyst, Inc., and Rainbow of Hope, aka Rainbow of Hope Foundation.