We recently had an at work injury; of which we believe the cause to be either from stored energy within a capacitor, or possibly static energy discharged.
Scenario: Electrician is in an elevated man basket connected to a crane and is attempting to replace a broken HID lamp in a parking lot lighting fixture. Inadvertently, the electrician makes contact between a grounded surface and one of the electrodes. Said electrician experiences a sensation to his hand. It is remaining to be determined if the capacitor was the culprit, or if friction from wind (due to the high elevation of the fixture) caused a static buildup which was released through the electrician.
Me, personally, I'm inclined to believe this was stored energy within the capacitor of the HID system. Assuming the circuit was properly de-energized & LOTO; if the capacitor had not been de-energized for an extended period of time (allowing "bleed off") there would still be a potential hazard present. With this stance, proper protocol would suggest that the capacitor should have been removed or had its energy released prior to attempting to remove the broken lamp.
In the old days one might place an insulated screwdriver across the capacitor and release the energy but for an inexperienced electrician this may create an additional hazard (i.e. using an uninsulated tool, inadvertenly making contact with the capacitor, etc). Is there a better process for discharging a HID lighting capacitor? Does anyone know of a resource which may outline the "better way"?
Any thoughts or experiences are most certainly welcome. This is an attempt to prevent this from happening in the future.