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Made by Monkeys

Double-Lock the Lock-Outs, or Lose a Hand

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rcwithlime
User Rank
Silver
Good posting
rcwithlime   3/19/2012 10:09:07 AM
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Sounds like the companys you were working for/with were really on the ball. There are so many co's fined by OSHA for repeat offenses, when the cost could have been applied appropriately

rickgtoc
User Rank
Gold
Re: LOckouts and the defeating of same.
rickgtoc   3/19/2012 1:13:15 PM
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I left out the 'Try' component in my earlier post, but that was a required component of the process.  Verify that the equipment cannot not be energized after the locks are in place and before a permit is issued to work on the system in question.

And with regard to another posting about an employee leaving the site without removing his/her lock - I know of a case where an employee did just that.  The mill contacted the employee and required him (in this case) to return to the site to remove the lock.  The time was unpaid.  To make this stick, you have to have a committed company safe work culture, and other parties(unions, vendors) have to be committed as well.  It should make sense to the union guys.  Who wants to go home missing a limb or in a pine box at the end of the day?  For vendors and contractors, you make the expectations clear, hold them to those expections, AND ask them to make it known if it seems that anyone else at the site is not meeting those same expectations.  The principle is that nothing we do is worth the cost of an injury.

bdcst
User Rank
Platinum
In a previous era..
bdcst   3/22/2012 3:59:06 PM
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Before the days of OSHA LOTO rules and devices we had safety interlocks.  This, of course didn't stop anyone from disabling them.  But anyone responsible for safety of personnel or of themselves would test interlocks to see if they were still functioning as intended.

Too many broadcast engineers were electocuted by transmitters turned back on remotely by studio personnel while the engineer was inside the cabinet at the remote mountain top tower site!  Has anyone seen Paul?  And why are we off the air this morning?

Always working with a buddy rather than working alone in the middle of the night is the right precaution but is all to often not made available to personnel due to budgetary constraints.

Never trust interlocks to work.  Besides you don't want to come in contact with live primary power rails even if the HV supplies are interlocked off.  I always pulled the fuses or disconnects and then tested with a voltmeter to be sure all input power terminals were cold.  Never send someone else to do the LOTO.  Witness it yourself to be sure it was done right.

I knew of a semi retired older broadcast engineer who did a small station owner a favor and came by to repair his AM transmitter.  He asked the owner to throw the main circuit breaker off.  Turned out the breaker panel had been illegally set up with single pole breakers, rather than double pole interlocked for the 230 VAC feed to the transmitter. The helper flipped one breaker handle off.  The old engineer happened to touch the remaining hot leg (120VAC) getting a stiff surprise.  He had never before gotten a significant electric shock.  He sat down and turned pale.  When he recovered he left, vowing to never come back and to make his retirement perminent. 

Some transmitters do not have "Jesus sticks" aptly named grounding devices that when applied to charged terminals can create quite a loud blinding flash.  Besides locking out energizable circuits, grounding the heck out of anything you may be working on is another good precaution.

I once had some work to do on a brand new NEC (made in Japan) UHF TV transmitter.  Klystron tube beam current power  supply voltage was in the 30 kV range.  The schematic diagrams showed interlock switches guarding every access door and panel to the transmitter.  But on further examination I noticed the switches were wired to TTL logic chips in the controller!  Should one trust their safety on TTL logic?  Of course not.  Proper design would require the interlock switch to directly open the circuit to a main contactor coil or its pilot relay thus preventing startup.  TTL logic could easily become noisy, leaky or shorted, thus rendering the interlock useless.

Keldawwg
User Rank
Gold
Re: When you're right, your right.
Keldawwg   3/22/2012 6:25:24 PM
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This article reminded me of another thing that I had happen to me twice, and an acquaintance of mine lost his right hand...

When I was 16 I got a job at a Shell gas station near my parents house... This was back in the days when full service gas stations still existed in California. I was a gas station attendant/service truck driver (We were right next to a large shopping mall, and several times a week someone would leave their lights on and need a jump start...)

Anyway, we would always ask if we could check under the hood... We checked oil, radiator overflow tanks, power steering fluid, etc... We would check antifreeze if asked, and also the battery if asked (Sealed maintenance free batteries were not common in those day, I think only Delco had them that I ever saw.

Anyway, twice I would be under the hood checking things and right when I was reaching for the power steering cap, the idiot behind the wheel (1 woman, 1 man... So it was evenly divided between the sexes as to who were the biggest idiots...) started the car!

Most power steering pumps were fairly buried, and frequently you had to reach through an alternator belt to take the P/S cap off... That's how the guy I knew lost his hand...

I would ask if they wanted me to check under the hood, and if they said yes I asked if I could have the keys. After I gave the keys back, I would ask if they wanted their transmission fluid checked, because the car had to be running to do that.

 I had several people get really mad at me, but when I explained why most were ok with it... I had maybe 10 or 15 people come back and complain to the station owner that I wouldn't check under their hood unless they gave me their keys... The station owner gave those complainers coupons for a discount on an oil change, and he would always come over to me and tell me I had another complaint... Then he would stare at me for a five count, and say that at least when he fired me I could hitchhike home with my choice of which hand I held out...

The thing people really need to remember is that there are a lot of idiots out there, and you have to protect yourself from them whenever you can...

 

Jon Titus
User Rank
Blogger
Even scientists got safety training
Jon Titus   3/22/2012 7:03:05 PM
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When I started work at a DuPont research lab back in '69, the company had a safety course for all new employees. We fought simulated chemical fires, put on Scott airpacks, practiced firts aid and learned about lockouts.  We couldn't even take jars of chemicals from the store-room unless we had a rubber bucket in which to carry them. The company stressed safety at every turn. I saw some electrical apparatus with lockout upon lockout when many teams were on the site. As others have said, never trust someone else to ensure your safety.

Rob Spiegel
User Rank
Blogger
Re: Even scientists got safety training
Rob Spiegel   3/22/2012 7:29:12 PM
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That sounds like a good set of safety procedures, Jon. That should be the usual practice. I was really quite surprised by this Made by Monkeys posting. I would think if nothing else, employees would be careful with lock-outs simpley out of concern for fellow employees.

Jack Rupert, PE
User Rank
Platinum
Re: LOckouts and the defeating of same.
Jack Rupert, PE   3/25/2012 7:25:40 PM
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That company needs a good safety overhaul or something.  The fact that somebody even had access to remove the lock is scary in it's own right.  I was at a location once where a guy forgot to unlock.  The machine was left inoperable until they reached him at home and made him drive an hour back to remove his lock.

rcwithlime
User Rank
Silver
I saw a truck driver lost his thumb
rcwithlime   3/26/2012 4:59:56 PM
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from reaching in with engine running. Got caught in steering belt.

Called ambulance, placed thumb in cup cushioned with ice and off he went.

Better safe than sorry.

cvandewater
User Rank
Gold
Running machines are to be respected.
cvandewater   3/29/2012 1:36:05 PM
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One friend was a promising automotive mechanic until the day he got his right index finger caught in the serpentine belt. He was fired from the place where he just had started (after his education as automotive mechanic) and could not find work due to his handicap....

I heard many years ago that the diver crews working on a ship will only dive after receiving all ignition keys. Don't know if they also were tagging.

notarboca
User Rank
Gold
Re: Running machines are to be respected.
notarboca   4/6/2012 11:43:20 PM
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cvandewater,  I too know of commercial divers who will not work on a ship until Tag Out Lock Out procedures have been followed and all keys are in the dive leader's wet suit.  Ya gotta do whatever it takes!

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