Abstract: At 2:00 p.m. on October 3, 2019, an employee was working as a janitor or cleaner for a firm that provided engineering, building, installation, maintenance and upgrade of energy, utility and communications infrastructure. Its customers are primarily in the utility, communications, and government industries. The employee and two other workers were cleaning an electrical vault. There was a 13.2 kilovolt electrical reactor in the vault. As the employee was cleaning near the reactor, he received an electric shock. He was hospitalized, and his left hand was amputated. The vault cleaning crew had been together for some time. Prior to this incident, the vault cleaning crew had entered and cleaned more than 79 vaults. In this incident, the employee had not been issued and was not wearing electrical protective equipment, such as sleeves and gloves. A language barrier made it difficult for the employer and the employee to communicate what sort of understanding the employee had of a minimum approach distance. His primary language was Spanish. Employees were not briefed on hazards associated with working near 13.2 kilovolt reactors in electrical vaults. Employees conducting cleaning duties inside electrical vaults did not receive briefing on hazards associated with the job, work procedures involved, special precautions, and personal protective equipment.