Abstract: On September 14, 2006, Employee #1 was performing remodeling punchout work. The floating manager instructed Employee #1 to go to the unit and replace a nonfunctioning smoke detector. The smoke detector was wired directly to the 120-volt power supply and also had a battery as backup power. Employee #1 went to the unit and entered the washer and dryer area, where the circuit breaker for the unit was located. He turned off the main breaker switch, but did not install a circuit breaker lock and tag. He then went to the second floor, where he proceeded to remove the bad smoke detector and install the new one. While Employee #1 was upstairs, a painter entered the unit and attempted to use his sprayer that he plugged into the wall. It did not work, so he went to the circuit breaker and turned the power on, not knowing that Employee #1 was upstairs replacing the smoke detector. Employee #1 was shocked by the 120-volt power that had been turned back on. As a result of the accident, Employee #1 suffered a temporary tingling and numbness in his left shoulder and upper torso. He was treated and released from a local medical facility.