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 Post subject: Plant debate over who is allowed in Electrical MCC Rooms
PostPosted: Wed Jan 05, 2011 8:44 pm 

Joined: Wed Jan 05, 2011 7:56 pm
Posts: 2
Location: Georgia
We are currently building a new facility, arc flash study provided is complete with several areas deemed as "Extreme". I have always thought of the electrical standards as a minimum way of life, but always go above the intended purpose.

We have a new Site Safety Mgr. that is persisting that I "go along" with having non-qualified personel entering an MCC room where unforseen hazards exist. He has thrown out a couple of regs from CFR 1910 that clearly state that the intended person of service install his/her lock and tag which I support lockout tagout 100% and nothing less but I don't agree with sending an individual into a hazardous environment and just pray nothing happens.

480v MCC's are 5ft from the automated 4160v MCC's in which face each other they contain 43 SMC's rated to handle the 600HP motors under severe loading. The other 2 issues I have is that each of the motor's are set up for automated reversing and the process techs that was hired have never worked in an industrial environment.

The lockout policy consisted of a written procedure for electricians to isolate and properly communicate with 2-ways with control operator for verification as identified on the HMI, group locks would be installed and the keys placed into a lock box at that time the intended person would take control of the keys (lockout) (I require 2 locks at all times) and also verify proper lockout with the control operator prior to beginning work. This was to limit the exposure to non qualified personel in which we have to maintain a minimum of 12 cal just to enter the MCC because of the circumstances. I am very passionate when it comes to fine lines vs. personal safety. Can someone help me with this, maybe it's me but I've witnessed an explosion without anyone in the room... What's your thoughts?


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PostPosted: Thu Jan 06, 2011 6:55 am 
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Joined: Wed Jun 04, 2008 9:17 am
Posts: 428
Location: Spartanburg, South Carolina
rsmcquaig wrote:
We have a new Site Safety Mgr. that is persisting that I "go along" with having non-qualified personel entering an MCC room where unforseen hazards exist.


Will the entry be made while work is being done on the equipment? If so, then the arc flash protection boundaries would apply to anyone not wearing appropriate PPE, qualified or not.


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PostPosted: Thu Jan 06, 2011 9:38 am 
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Joined: Wed May 07, 2008 5:00 pm
Posts: 819
Location: Rutland, VT
rsmcquaig wrote:
We are currently building a new facility, arc flash study provided is complete with several areas deemed as "Extreme".


This jumped out at me right away that a design is being done and the areas are being left as "Extreme" danger. This does not seem right to me. I would think that there are some things that can be done to lower the arc flash hazard during the design phase. Some things are:

1. Arc flash hazard relays
2. Smaller transformers (which means more equipment)
3. Arc resistant switchgear
4. Current limiting fuses upstream and away from buses
4. Bus differential protection

I am sure there are more but as a PE, I am bothered that more has not been done to lower the hazard. But I don't know the design constraints but would guess that $$$$ were the predominant design constraint.

Sorry just my 2 cents rant.

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PostPosted: Thu Jan 06, 2011 9:52 am 
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Joined: Mon Jun 02, 2008 11:58 am
Posts: 1103
Location: Charlotte, NC
wbd wrote:
This jumped out at me right away that a design is being done and the areas are being left as "Extreme" danger. This does not seem right to me. I would think that there are some things that can be done to lower the arc flash hazard during the design phase. Some things are:

1. Arc flash hazard relays
2. Smaller transformers (which means more equipment)
3. Arc resistant switchgear
4. Current limiting fuses upstream and away from buses
4. Bus differential protection

I am sure there are more but as a PE, I am bothered that more has not been done to lower the hazard. But I don't know the design constraints but would guess that $$$$ were the predominant design constraint.

Sorry just my 2 cents rant.


"Design build" = Win bid and cut corners


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PostPosted: Fri Jan 07, 2011 2:52 pm 

Joined: Mon Dec 06, 2010 11:33 am
Posts: 4
Location: LUBBOCK TX
It starts with just a drip

Sounds like there needs to be a work practices update to accomodate "unqualified" personnel.
From my experience, once you start "BENDING" the rules, it allows methods which are unacceptable and dangerous.
If the current procedure identifies electricians as the only "QUALIFIED" personnel who may perform LOTO; how can you insist on strict application in one instance, but not in others. If that's the practice, might as well allow a free for all.


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PostPosted: Fri Jan 07, 2011 7:48 pm 

Joined: Wed Jan 05, 2011 7:56 pm
Posts: 2
Location: Georgia
Thanks for the information

There were other approach measures that could have helped mitigate the extreme dangers but to clarify = 480 > 1800A > & high impedance are all to blame...

All the primaries are fused including the subs, the only way to shut down power is to hope like heck the fuse goes at least until Georgia Power arrives.

The other controversy is the definition of "authorized" by OSHA vs. "Qualified" by NFPA.. the process is very complex and fast switching of 4160 motors forward / reversing through delta SMC's..

the concern is actually for the employee's by limiting the access to these areas as much as possible. On the other hand some want to have more authority than others if you understand what I mean... We have folks that have never seen or even used loto but know more about the procedure than OSHA. It's a very dangerous place never the less but if an injury occurs and your asked about known hazards that exist how do you protect your liabilities to neglect?


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PostPosted: Tue Apr 05, 2011 10:14 am 
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Joined: Sun Sep 23, 2007 5:00 pm
Posts: 114
Location: Calgary, Alberta, Canada
A company's Electrical Safety Program would define worker Roles & Responsibilities.

As well I am concerned that a lot of people are assuming that energized electrical equipment is Normally not safe and will arc flash at any time. This is not true and we need to ensure we do not create an environment of fear of electrical equipment.

If your electrical equipment is approved, installed to the NEC or CEC, the environment is controlled, aging and maintenance are controlled energized electrical equipment does NOT normally arc flash. An Abnormal condition is required for an arcing fault to occur that is not cleared that leads to an arc flash event.

For low voltage isolations with the electrical equipment door closed and following an approved procedure all workers can complete this isolation and do not require any arc flash or shock PPE, Tools and equipment.

If a very conservative approach is taken without appropriate risk assessment then you may choose to have a Journeyman Electrician perform this task, but it is not necessary if you review both the hazard and the associated risk. Your company's Electrical Safety Program provides the policy and practice, NOT 70E or Z462, they are just Standards.

Most who read this will most likely not agree with me, but I would recommend that you research Occupational Health & Safety Management Systems, Hazard Task Analysis, and Risk Assessment.

If we continue this trend in thinking we will not have enough electricians to go around and will also make North America less competitive. Safety is a priority for energized electrical work YES, effective application of preventive and protective control measures that were not practiced in the past now take the probability of an electrical incident to even lower that it already was. We need to be able to operate our Refineries, Manufacturing Plants, etc. and we need Non-Electrical Workers to have access to electrical equipment for reading information from meters and displays, and for low voltage isolations and to apply locks to high voltage switchgear after a Journeyman Electrician completes the isolation on the high voltage equipment.


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PostPosted: Wed Apr 06, 2011 5:43 am 
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Joined: Thu Jan 10, 2008 8:49 pm
Posts: 498
Location: New England
Assuming all your gear is in deadfront, and there is no live work going on at the time, there are no regulations or restrictions that prevent personnel without HRC to enter the room and perform LOTO. This would not be true if they were operating switchgear, but for MCC buckets of typical application it would be.

I don't know how we have extended Arc Flash to include operation of deadfront equipment.

LOTO is a very important safety precaution. I don't know that I want an electrician locking out equipment that I have to work on, and having his lock and not my lock on it, or being able to do the LOTO myself. I know I can't take all 180 workers and outfit them in HRC for the infrequent LOTO's they perform.


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PostPosted: Wed Apr 06, 2011 10:07 am 
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Joined: Mon Mar 29, 2010 5:02 am
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haze10 wrote:
Assuming all your gear is in deadfront, and there is no live work going on at the time, there are no regulations or restrictions that prevent personnel without HRC to enter the room and perform LOTO. This would not be true if they were operating switchgear, but for MCC buckets of typical application it would be.

I don't know how we have extended Arc Flash to include operation of deadfront equipment.

LOTO is a very important safety precaution. I don't know that I want an electrician locking out equipment that I have to work on, and having his lock and not my lock on it, or being able to do the LOTO myself. I know I can't take all 180 workers and outfit them in HRC for the infrequent LOTO's they perform.


I agree 100% with you on how Arc Flash has grown and is being misinterpretted in "what is coverred". People will develop an extreme and unwarranted fear of electrical gear and rooms..

As for locking out gear, being an electrician, there is some stuff that I think is better to be verified by an electrician. One of the companies I worked with wanted me to verify fractional horsepower motors for their millrights to work on. I would go out and turn the local switch OFF, watch the motor stop and give it my stamp of approval. This was pretty much a waste of my time, since I think they can figure out when the motor was OFF. For the higher voltage isolations (208-5 kv) I would do the isolation and make sure the breaker was properly racked out or isolated. Then I would install a lock from the lock box for that job OR a set of scissors and an electrical craft lock. Part of the LOTO procedure then called for the operator to try and start the equipment. That was the second check on the electrical lock out (as there was a status from the breaker being "READY" for use).

If the breaker was not being physically isolated (racked out) but rather the disconenct locked out I tested 7 points to verify the unit was de-energized. First verify my meter to a known LIVE source, then on the LOAD side of the breaker from L1/L2/L3 to ground, then L1 to L2, L1 to L3 and L2 to L3. Then it would be ready to be locked out. Obviously as the door was open for testing I had my PPE on rated for that gear (ie. gloves, Faceshield, etc)...


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PostPosted: Wed Apr 06, 2011 1:26 pm 
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Joined: Mon Mar 29, 2010 11:52 am
Posts: 110
Location: Yankton SD/ Lead SD
glen1971 wrote:
I agree 100% with you on how Arc Flash has grown and is being misinterpretted in "what is coverred". People will develop an extreme and unwarranted fear of electrical gear and rooms..

As for locking out gear, being an electrician, there is some stuff that I think is better to be verified by an electrician. One of the companies I worked with wanted me to verify fractional horsepower motors for their millrights to work on. I would go out and turn the local switch OFF, watch the motor stop and give it my stamp of approval. This was pretty much a waste of my time, since I think they can figure out when the motor was OFF. For the higher voltage isolations (208-5 kv) I would do the isolation and make sure the breaker was properly racked out or isolated. Then I would install a lock from the lock box for that job OR a set of scissors and an electrical craft lock. Part of the LOTO procedure then called for the operator to try and start the equipment. That was the second check on the electrical lock out (as there was a status from the breaker being "READY" for use).

If the breaker was not being physically isolated (racked out) but rather the disconenct locked out I tested 7 points to verify the unit was de-energized. First verify my meter to a known LIVE source, then on the LOAD side of the breaker from L1/L2/L3 to ground, then L1 to L2, L1 to L3 and L2 to L3. Then it would be ready to be locked out. Obviously as the door was open for testing I had my PPE on rated for that gear (ie. gloves, Faceshield, etc)...


I agree with your procedures Glen1971. The only minor point is that it should be an 8 point test. You need to re-verify your meter on the known live source after you perform your load side voltage tests.


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PostPosted: Thu Apr 07, 2011 10:20 am 
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Joined: Thu Jan 10, 2008 8:49 pm
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Location: New England
I agree also Glenn. My comments were not related to the equipment that is typically LOTO'd by electricians. Electricians usually have the HRC clothing and training of Arc Flash. My comments were directed for the typical 480V and below equipment typical of industry, and the operators/techs in those industried.


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