There are multiple things mechanics do that create a lot of sparks. Some are destructive, some are constructive: metal cut-off wheels, acetylene torches, and welding. When doing any of these, you need to be aware of where your sparks are going. You don’t want to be sending them at a pile of oily rags, paper, gas cans, other cars.
I was working on a Honda Odyssey, torching the nuts off of part of the exhaust. When you’re melting and blowing away metal, it sends 1000+ degree blobs of metal splattering onto the floor. I had finished torching off what I’d needed to, and was doing some other tinkering for a couple minutes, when I saw flames out of the corner of my eye.
I looked and the plastic engine cover I had set aside on the floor several feet away, was on fire. One of those bits of molten metal had landed under or on the cover, set it on fire, and was melting a large hole in it. I noticed it at the exact same time as a few other techs, and I quickly stomped it out.
Nobody will notice that extra hole, right?
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