Shock Hazards

[Roy D. Cooke, Sr]

FLASH

11-02-FL

July 2011

Electrical Shock Hazards associated with older fuse panels

Electrical installation methods, codes and product standards in Ontario and across North America have evolved greatly over the past 100 years. Over time, the standards for electrical products and installations have been updated to address safety issues that have arisen.
Current Ontario Electrical Safety Code (Rule 14-206) and product standards (CSA Standard C22.2 No.29) require panelboards containing breakers or plug fuses to have barriers and/or covers that eliminate exposure to energized parts; where these panelboards are readily accessible to unauthorized persons for operation of the breakers or changing of fuses.
Ontario Electrical Safety Code Rule 14-206 states:
14-206 Fuseholders for plug fuses
readily accessible Fuseholders for plug fuses shall be of the so-called "covered" type where to unauthorized persons.
Some of the homes, apartments and other buildings across Ontario still have old electrical fuse panels that were installed in the era prior to 1940.Those panels complied to the codes and standards of the time. If maintained properly, complete with the correct size and type fuses, these panels will still be adequate to protect the electrical circuits and equipment. However, it has been identified that opening the panelboard cover of some of these fuse panels gives access to bare and exposed energized terminals, which may pose electrical shock hazards to unqualified persons (see photo F1 showing the panelboard with the cover opened).
Photo F1 – Bare live terminals in old fuse panel
Many of these older electrical fuse panels may not provide adequate shock protection for persons replacing fuses. Persons are exposed to energized connections and conductors when accessing the fuses.
Due to the potential shock hazard associated with these open type panels in residential dwellings, the Electrical Safety Authority will be mandating the following when the dwellings are Rental/Tenant occupied (not owner occupied):
• Fuse panels shall be provided with covers that are only capable of being opened with the use of a key/tool; and
• a warning label shall be placed on the cover of each panel stating

"

Danger Exposed Energized Parts, Consult Landlord for Service"
(or equivalent wording).

This will meet the intent of the current code and standards by rendering the internal parts of the panelboards not readily accessible. FLASH 11-02-FL
Additional Electrical Safety Authority Recommendations
If a property owner wishes to upgrade their older electrical panels to provide a higher level of electrical safety than the minimum mandated above, other available options could be:
1) Replace the fuse panels and panel enclosure with new breaker panels
2) Retro-fit new breaker panel interiors into the existing fuse panel enclosures (contact breaker panel manufacturer to see if breaker panel retro-fit kits are available for existing enclosure dimensions).