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Lockout-Tagout

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Re: Lockout-Tagout

#31

Post by Gibbon1 »

fingerlocks wrote: post #27
ebiester wrote: post #13

Earlier quoted context omitted.

How would you recommend people working on their own house implement anything more than turning off the circuit breaker? (I'm not doing anything electrical in general, but sometimes small fixes are necessary for home owners.)

If we’re being honest with ourselves, few (if any) home owner is ever going to go through with locking circuit breakers. Because it’s completely overkill. In the Real World, you’ll just tell your wife/kids/roommates “Hey don’t touch the fuse panel until I’m done doing this thing” and it’s not an issue.

One of the funniest things I saw like that was my dad on a ladder in a closet trying to sort out a switch and light fixture with a voltmeter and my special needs brother repeatedly going outside and flipping off the circuit breaker. Leaving my dad cursing on a ladder in the dark.

Re: Lockout-Tagout

#32

Post by Gibbon1 »

taneq wrote: post #23
devb wrote: post #16

Earlier quoted context omitted.

I think OP is referring to a job site where people coming and going have access to the panel. If you're home alone or only have a small handful of people to keep in contact with then it's far less of an issue.

In those cases you're 'probably fine' but if someone gets home while you're working, sees that the power is out, and goes to check the circuit breaker (as you've probably trained them to do) then you could still get zapped without warning.

That's why central air conditioners are supposed to have a disconnect within sight of the unit.

Re: Lockout-Tagout

#33

Post by ISL »

RandomBacon wrote: post #12

Always verify the equipment you are working on is still physically LO-TO. I heard a story about one person who LO-TO a breaker on Friday, and Monday it had power when he went to work on it. The guy went to check the breaker, and the breaker was sitting on the ground with the lock still attached, and a new breaker in its place.

Oh, wow. That's tantamount to attempted manslaughter.

Re: Lockout-Tagout

#34

Post by Gibbon1 »

csours wrote: post #24
RandomBacon wrote: post #12

Always verify the equipment you are working on is still physically LO-TO. I heard a story about one person who LO-TO a breaker on Friday, and Monday it had power when he went to work on it. The guy went to check the breaker, and the breaker was sitting on the ground with the lock still attached, and a new breaker in its place.

Hooo boy. I think there might be a few more breakers on the ground if that was me.

You misspelled 'teeth'

Re: Lockout-Tagout

#35

Post by ajhurliman »

taneq wrote: post #9

After working in mining for a long while, where this kind of isolation procedure is standard and is taken very seriously (pretty much any breach of procedure is an instantly firable offense) it's terrifying coming back home and seeing people working on house wiring etc. with nothing more than a turned-off circuit breaker protecting them from electrocution or other injury. I've seen some trades start to pick up isolat…

Nuclear also takes this very seriously.

Re: Lockout-Tagout

#36

Post by zaarn »

ebiester wrote: post #13
taneq wrote: post #9

After working in mining for a long while, where this kind of isolation procedure is standard and is taken very seriously (pretty much any breach of procedure is an instantly firable offense) it's terrifying coming back home and seeing people working on house wiring etc. with nothing more than a turned-off circuit breaker protecting them from electrocution or other injury. I've seen some trades start to pick up isolat…

How would you recommend people working on their own house implement anything more than turning off the circuit breaker? (I'm not doing anything electrical in general, but sometimes small fixes are necessary for home owners.)

What I learned when doing electrical work in germany, the procedure for safe electrical working is as follows:

- Switch off (at circuit breaker)

- Prevent switching on (lock the breaker)

- Check voltage free (multimeter cleared for 230V/120V operation with long, isolated test leads)

- Ground and short (put a plug into the socket connecting earth, live and neutral, you can DIY that at home safely by cutting open an unused cord and soldering all three wires together)

- Cover nearby powered equipment

Re: Lockout-Tagout

#37

Post by roenxi »

taneq wrote: post #28
caseymarquis wrote: post #26

Earlier quoted context omitted.

After working on high voltage circuits as a lineman for a couple years, and currently writing software for industrial machinery and regularly working in industrial machining cabinets, I think that applying the same level of precaution used for mining to doing minor work on a 100V circuit is being a bit overzealous. To be fair, you're never going to get hurt by being superfluously safe, but at the same time I don't ex…

Honestly if our mains was 110V rather than "240V" (read 250-260V thanks to all of the rooftop solar in our area) I'd probably be a bit more casual about it. I've been nipped by ~100V from poor earthing and it's not that bad. 240V hurts.

I've no particular experience working with electricity so maybe you just know what you are doing - but at risk of being a know-it-all on the internet that is not a very safe approach. In an industrial setting any electricity related accident is cause for a trip to the hospital no matter how minor.

For starters you don't want to be casual about 110 volts [0] and for seconds the systems that control heart rhythm use electricity. An electric shock can cause a heart to just stop some hours later (happened to a family friend as far as we can tell).

It is invisible, can kill and humans don't have the right nerves for pain to be an indicator of how bad the damage is. Electricity is hazardous and work on it should leave no scope for surprises.

[0] https://www.asc.ohio-state.edu/physics/p616/safety/fatal_cur...

Re: Lockout-Tagout

#38

Post by Scoundreller »

Gibbon1 wrote: post #32
taneq wrote: post #23

Earlier quoted context omitted.

In those cases you're 'probably fine' but if someone gets home while you're working, sees that the power is out, and goes to check the circuit breaker (as you've probably trained them to do) then you could still get zapped without warning.

That's why central air conditioners are supposed to have a disconnect within sight of the unit.

I thought it was for easy-money from new/unfamiliar home-owners.

https://youtu.be/fUAIBZKeK74 For the Dateline Special.

Re: Lockout-Tagout

#39

Post by dgemm »

taneq wrote: post #9

After working in mining for a long while, where this kind of isolation procedure is standard and is taken very seriously (pretty much any breach of procedure is an instantly firable offense) it's terrifying coming back home and seeing people working on house wiring etc. with nothing more than a turned-off circuit breaker protecting them from electrocution or other injury. I've seen some trades start to pick up isolat…

I worked in mining as well and it's often terrifying watching the stuff that goes on all day at every urban construction site, even the things you can see from street level. Construction workers that stand directly below suspended crane loads in order to guide them down to the ground is something I see constantly and makes me nervous just to watch. If you tried anything like that at any of the mines I worked at you would be immediately escorted off site and probably blacklisted from working there again.

Re: Lockout-Tagout

#40

Post by fargle »

ebiester wrote: post #13
taneq wrote: post #9

After working in mining for a long while, where this kind of isolation procedure is standard and is taken very seriously (pretty much any breach of procedure is an instantly firable offense) it's terrifying coming back home and seeing people working on house wiring etc. with nothing more than a turned-off circuit breaker protecting them from electrocution or other injury. I've seen some trades start to pick up isolat…

How would you recommend people working on their own house implement anything more than turning off the circuit breaker? (I'm not doing anything electrical in general, but sometimes small fixes are necessary for home owners.)

Simple answer: close the breaker box lid and put a cheap padlock on it. You don't need a tag or special clip. That ensures that your wife or roommate doesn't try to flip the breaker back on while your arm is in the garbage disposal or you are holding the hot wire with your teeth.

You can and should use a test light or DVOM to verify the power is out.

You can and should treat the wires as if they were "hot" anyhow. You should keep a wire nut on the hot wire. Don't actually put any of the wires in your teeth.

Now. You could do all that, but what I do at home is carry a lot of insurance and work "hot". I don't care about 120V or even 240V. I make sure what I'm touching one arm at a time with no ground path through my heart. Don't stand in water. Simply just don't touch the hot wire. I learned to work hot on a piecework job that payed by units completed and that was about 1000% more if you could work hot. And, you can, if you manage the risk. If you mess up 99% chance you'll say "OW" and NOT do that again. I wouldn't play Russian roulette with 1:6 odds. But 1:100 (die from) x 1:100 (mistake) x 10 hours per year (occasional fixes), fine not worth the bother. Far more chance of dying falling off the ladder than electrocution. DON'T stand on rolly chairs.

Now at an uncontrolled job-site, where I'm payed by the hour, 2000 hours/year? NEVER. It's a lot different when you are a company of one vs. many. I know what I'm doing, and while I make mistakes, I can guess how often. If you have more than 0 co-workers, you cannot trust or predict their mistakes.

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