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Close all box openings. DIY safety inspection cont'd

All unused holes must be closed. It's a code requirement and fire hazard.



Free DIY tips from Electrician Toronto

Cover all openings and fix holes in electrical boxes and panels. Install all missing cover plates (at your own risk).

Open holes and missing knockout fillers lead to:
foreign objects accidentally entering energized enclosures
shocks and injuries (protect kids from sticking in their fingers)
rodents crawling into an inviting panel that looks like a perfect nest to them
dangerous sparks jumping out from inside the boxes if there is a short or localized fire inside

Take a flashlight and visually inspect every junction and outlet box in the utility room, garage or basement. Check all sides and front cover plates of all panels, large and small. You will likely find a few large holes. Any round or rectangular opening of any shape a quarter inch or larger is a hazard.

If you are 100% confident in your abilities, shut down one-by-one the power to all circuits. And THEN turn off the main breaker of shut off fused switch. (Did you forget about the flashlight?)

Make a list with new entry for every hole found, measure its size and take a picture while holding the measuring tape in place. For panels with rectangular openings on its cover plate, make a bigger shot or two capturing panel's model number, brand and breakers.

Your best bet is finding a nearby store. Google three words, your postal code and "electrical supply" like this https://www.google.ca/search?q=M6H+4B3+electrical+supply you can then click on maps too.

Now you can go buy cover plates, knockout plugs, filler plates, and/or knockout fillers. Do not forget to take the list, your smartphone or laptop with images.

Make sure the power is still off and push-in a correctly sized plug into every hole. You may need to tap some of the fillers into the place with a hammer.

Some round plugs won't go in or stay in. You may need to first squeeze the tub bases toward the centre (use pliers), insert and then unbend or open the tabs up like flower petals from inside the box (use pliers or screwdriver) to make the knockout filler stay in its normal position.

Then approach the panel and force rectangle fillers into its front openings. Do not remove the cover plate. It could still be highly dangerous for you.

Finished? No yet. Now, you have to turn ON the main breaker FIRST. THEN one-by-one put all circuit switches ON.

Keep in mind, that Ontario regulations call the above "an electrical work" and an ESA paid inspection is mandatory.


Not sure how to do it? Call an expert


(289) 217-9643
please call from 7am to 7pm
Weekdays, weekends & evenings

NO calls after 7pm please



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