Minor electrical burns to the tip of index and little finger

Incident Investigation

Minor electrical burns to the tip of index and little finger

June 15, 2019

Boiler, PV and Refrigeration

Reference Number:

II-867256-2019 (#13632)

While servicing a heating and air conditioning unit the qualified technician’s hand came in contact with energized equipment and received an electrical shock.

An equipment panel cover normally shields energized components of the unit, a panel cover was not in place at the time of the incident.

While working on a heating and cooling unit an electric heating coil was exposed. The technician’s hand unintentionally came in contact with the energized heating coil.

To facilitate testing of the air conditioning equipment, a panel cover was removed exposing electric heating coils. The technician reported that: while troubleshooting the issue with the equipment he had his hands on the access panel to the contactors for the heating coil, when his left hand slipped on some dust and his index finger touched the live heating coil, resulting in a 347 Volt electric shock. The 575 volt- 3 phase electric heater is controlled by a 2-pole contactor, so that even when the heater was not operating it is still energized with a 347 Volt potential.