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 Post subject: Lockout tagout for non electrical hazard
PostPosted: Mon Feb 07, 2011 11:43 am 

Joined: Mon Jan 10, 2011 6:34 am
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Location: Ohio
I have read posts on here concerning lockout tagout of equipment for servicing/maintenance purposes but still do not know where to go with our current lockout/tagout program. Our current program would not require employees to have Cat 0 ppe on when performing a lockout to perform maintenance or cleaning on a machine. I read in the 09 nfpa 70e table 130.7 that CB or fused switch operation with covers on would be a Cat 0 hazard. I read about electrically safe conditions and the requirements for that (assuming that you are going to be working within limited approach boundary with exposed conductors) where a zero volt condition has to be established, but what about when the doors are closed and you are not going to be opening them and the work would be on a machine located outside of the arc flash boundary. Could a non-qualified person even throw a disconnect on a panel since they would technically be interacting with the circuit. (If they had Cat 0 PPE) I know what some people on here have said but I would like to know what the general concensus about the issue is.

With reading the nfpa 70e I could make argument that only my mechanics could throw the disconnect because they are qualified and would then have to verify the electrically safe condition before another employee could work on the equipment to clean/service it (that employee also putting a lock on the equipment once the mechanic deemed it electrically safe)

From what I read with Osha...I would think that non-qualified employees could turn off the power, lock out the machine, and then "verify isolation of the equipment by operating the push button or other normal operating controls" (I would say they would have to have Cat 0 PPE on though when doing this)

Any opinions and reasons for reaching that opinion or examples of what you are doing at your plant be greatly appreciated


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PostPosted: Mon Feb 07, 2011 3:51 pm 
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It will absolutely depend on the maintenance and application of the switches. Something that is operated regularly and maintained per manufacturer's recommendation can be expected to perform safely.

However many disconnects have not been operated for years, have enclosure rating inadequate for their environment, are applied where fault currents exceed there ratings, and so on.

Opening a disconnect for a motor that has been turned off and then re-closing it after a belt has been changed, is not the same thing as turning it back on after the motor has been unwired and replaced.


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PostPosted: Tue Feb 08, 2011 1:31 pm 
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Based upon the description you provided I would recommend this:

You are following the Tables, so I take it no engineering study has been done. Note in your Arc Flash Policy, that the use of the Tables will only apply to electrical work, and not to routine LOTO unless they exceed (400Amps, or 800 Amps, or whatever you consider to be outside of the routine).

The conflict comes into play because 70E says you need FRC when switching significant energy sources. Most industrials have interpreted that to be Switchgear, but it can also be high amperage loads.

The Table does require FRC 0 for switching breakers and switches. But this also conflicts with the text of the code which is based on 'live' work. Switching is not 'live work' unless it is of significant energy. NFPA did not define significant energy, so you have to, or at least "industry norms" would apply. As part of that "industry norm" I wouldn't consider anything below 400Amps as 'not' significant. Some will agree and disagree with me.

What is troubling to you is how to resolve the conflict. That is done with your site's Arc Flash Policy. There is no OSHA law requiring you to have an Arc Flash program specifically. The OSHA General Duty Clause says you have to follow safety norms within your industry. OSHA has stated that they won't 'fine' anyone for a arc flash incident IF they are following NFPA 70E. So your policy is based upon NFPA 70E. But where 70E fails to make specific and clearly defined regulations, like no live work above 40 cal, then you fill in the blanks as best you can that keeps you working.

I do not believe 'all' switching constitutes FRC. We do not have secretaries dressing out in FRC to turn on their light switches in the office. Whether the light switch circuit is switched at the wall of the office, or the breaker in the panel, the risk is relatively similar (at least in my opinion). The industries that I have worked in, which employ some 500 persons, all permit their operators to perform LOTO without FRC. Is that the beginning of a norm?

If there was an accident with an operator without FRC performing LOTO, which would be remote because LOTO's are usually only performed by operators on a routine and repeat basis for equipment designed for that purpose - what would be the outcome.

OSHA arrives to perform an investigatation. OSHA: "Was the person in FRC" Owner: "NO". OSHA: "Do you have an Arc Flash Program" Owner: "Yes, and its written and practiced in great detail" OSHA: "May we see it"...."I see that your policy says you are following the Table method but yet that operator was not dress in FRC" Owner:"That person was not performing electrical maintenance. 70E does not specifically mention LOTO. 70E does mention switching significant energy sources, but this device was below the guidelines established by engineering". OSHA:"we'd like to cite you for not having an Arc Flash program in accordance with the GDC, but we can't - because you do have a program. But we need to leave you with a recommendation that your engineering dept re-evaluate the cutoff energy level"

The point of all this is, you can do LOTO without FRC, up to a defined limit, but all of this has to be documented beforehand in your policy.


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PostPosted: Wed Feb 09, 2011 9:53 am 

Joined: Mon Jan 10, 2011 6:34 am
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Very good point. We are currently using the tables but the analysis is scheduled for the end of the month. I will make sure that we do note in our policy when the switching will require Cat 0 and when it will not. Thanks


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PostPosted: Wed Feb 09, 2011 5:26 pm 
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mvann81 wrote:
Very good point. We are currently using the tables but the analysis is scheduled for the end of the month. I will make sure that we do note in our policy when the switching will require Cat 0 and when it will not.....


Glad to hear that you are getting an actual analysis done instead of relying on the Task Tables in NFPA 70E. Way too many people ignore those footnotes at the end.

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PostPosted: Thu Feb 10, 2011 1:54 pm 

Joined: Sun Dec 12, 2010 5:00 pm
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Location: Idaho
Electrical Lead

So am I correct that if we write in our LOTO policy that the everyday employee does not need HRC clothing it is OK with OSHA when performing LOTO? We are trying to figure this same thing out at our plant because the new issue of NFPA 70E has the "interacting with equipment" fpn. Our hazard analysis has been done, but since we have a label on the equipment that states the flash hazard boundary, no person may enter this space without the appropriate PPE which is violated when they throw the handle to lockout a piece of equipment. I personally still believe that if LOTO is followed properly there is no load on the disconnect or switch, therefore no arc, so no hazard, but even our local OSHA reps will not state an interpretation of this because they say we have to provide a hazard free workplace so PPE is necessary although they will not "explicitely" say this. NFPA writers say the same thing that these rules are for electrical safety in the workplace and does not have any reference to the already suited up electrician or the pedestrian that happened to walk through the arc flash boundary. Someone needs to have OSHA specifically address the LOTO issue when it pertains to arc flash and not just the NFPA. :confused:


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PostPosted: Fri Feb 11, 2011 7:25 am 
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gastoor wrote:
We are trying to figure this same thing out at our plant because the new issue of NFPA 70E has the "interacting with equipment" fpn.


Actually the FPN says interacting with equipment in a manner that creates an arc. All of the words are important.

The FPN also goes on to say that normal operation of properly applied and functioning equipment may not pose an arc flash hazard.


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PostPosted: Fri Feb 11, 2011 8:08 am 
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....The FPN also goes on to say that normal operation of properly applied and functioning equipment may not pose an arc flash hazard. ....

I was a field engineer for a major manufacturing company for six years, now teach safety seminars and perform power system studies. My thirty years of experience have shown me that you can not visually tell when the equipment is properly applied or functioning. Electrical equipment is normally static and is not mechanically operating, and you cannot tell if it is going to function properly or not. Always wear the proper PPE when operating electrical equipment.

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PostPosted: Fri Feb 11, 2011 3:18 pm 
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All the boundary information on the label is in referenece to live work. The operation of a LOTO is done with a dead front. You are not opening the enclosure are you? So if the deadfront remains in place, the boundaries do not apply as its not live work. Your policy defines what switching significant energy constitutes, ie, switchgear, 800A, 400A etc.

I don't buy the argument that you can't trust the equipment to perform its operation. This disregards that the deadfront offers no protection at all. Which is does. While it is the more conservative route to take, not all industries can afford to buy FRC for every operator that needs a LOTO.
Not to be cavalier, but if the risk at work, is no more than the risk I took driving to work, then its acceptable to me. I think my risk of using the ATM at nite has a higher probability of serious injury, then throwing a 60A disconnect switch with doors closed. IMHO.


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PostPosted: Tue Apr 26, 2011 10:09 am 
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How to accomplish LOTO in policy.
Sorry for repeating myself but someone sent me an message with a question and my computer dropped out and I lost it.

The question was how to incorporate a no PPE required policy into an arc flash study.

These are two seperate issues. First, the study will be based upon IEEE1584 formulas. So in the end you will have one IE value on the label good for all tasks.

Second, you need to have a written policy that outlines how your are going to conduct your arc flash program. This includes your 'live work permit', 'what you consider to be routine work', how often is periodic training, a glove program, etc. Within this policy you will have a section for LOTO. In that section you state that HRC PPE will not be required for LOTO for any electricial equipment, known to be in good working conidtion, with all covers and fasteners secured. I would include an exception clause for draw out switchgear. If you want, and this is your choice, you can include it for some arbitrary amperage rating, say 800A and above.

If you want to discuss more send me another message.


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PostPosted: Wed Apr 27, 2011 9:11 am 
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The interpretation of interacting with equipment that is in good condition and has been properly maintained is open to interpretation as to:
how good is the maintenance and testing program,
how qualified are the technicians/electricans in the maintenance and testing of this equipment,
is the equipment maintained by an outside contractor
What is his reputation for doing quality work.
In addition, in performing LOTO, the mere opening of a disconnecting device does not constitute a full LOTO for a piece of equipment. It must be verified for the absence of potential, for which full PPE must be worn in accordance with the Ie or HRC. You cannot make a blanket statement about no PPE when performing LOTO.


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PostPosted: Wed Apr 27, 2011 5:36 pm 

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richxtlc wrote:
In addition, in performing LOTO, the mere opening of a disconnecting device does not constitute a full LOTO for a piece of equipment. It must be verified for the absence of potential, for which full PPE must be worn in accordance with the Ie or HRC. You cannot make a blanket statement about no PPE when performing LOTO.


Lets say you need to work in a switchboard with an incident energy >40 cal/cm sq. You have properly performed a LOTO at the overcurrent device ahead of this switchboard. Now you must complete the procedure and verify the absence of voltage in the switchboard. What PPE do you wear?

This question was asked in a class I was teaching today and I was unable to give a definitive answer. Made me wonder if I'm qualified to be an instructor in this stuff.


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PostPosted: Thu Apr 28, 2011 4:37 am 
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You must do LOTO the hard way. We follow the osha guideline:
1) Verify function of local run button
2) Disconnect (with covers on) and lock in off position, attach tag
3) Verify correct disconnect by trying local run button, observe no start.

If your LOTO is to disconnect wires or pull fuses, and you are going to open the covers or doors, then yes, you need PPE for that labelled IE.

With regard to 'blanket statements'. In order to maintain a conversation amongsts professionals, some assumptions are usually made. When statements are made about covers on, it would apply to an industry standard, i.e., all latches made, hinges in good order, no corrosion, no warpage, holes, etc. Same for proper maintenance, the equipment is in a clean dry place, there isn't crap dripping from pipes on it, there aren't broken pieces, missing screws, flash burns, etc.

Obviously, my statements regarding PPE and LOTO refer to areas that would be considered under normal industrial conditions. If you come to a piece of equipoment, and the covers are on, but there are latches missing, and empty conduit holes, and the bottom is rusted out, and there are sign of a previous arc flash - then not only do you need PPE - you need to don the PPE as you are running away. I wouldn't touch a piece of equipment like that even if I were wearing a suit of armor.

In my opinion, and I admit to being in the minority, PPE is not required for LOTO for equipment in good condition with covers on - at least according to my reading of the 2004 and 2009 Art 130.


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PostPosted: Thu Apr 28, 2011 5:43 am 

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haze10, your response still doesn't address my question. In this situation, you need to verify the absence of voltage, obviously with the covers off, in a piece of equipment with a labeled Ie in which no recognized PPE exists.

As I interpret NFPA 70E, this is a situation where you are required to do a task that is impossible to do while still being in compliance. I'm curious as to how others here perform the impossible.

I do like adding the step of trying to run equipment being fed, as this helps support the believe that power is disconnected, however the only sure way to verify absence of voltage is to test all the conductors to be worked on.


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PostPosted: Thu Apr 28, 2011 7:41 am 
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amphead wrote:
I do like adding the step of trying to run equipment being fed, as this helps support the believe that power is disconnected, however the only sure way to verify absence of voltage is to test all the conductors to be worked on.


Haze10 talks about general LOTO carried out by mechanics or even operators, for mechanical reasons (maintenance, cleaning, etc.). Not for electrical work.

The problem when workers other than electrical workers do LOTO is: do you need to dress them in a HRC3 kit or not, for the normal operation of the handle from the ON to the OFF position and reverse? For such tasks, verifying the local command of the machine/equipment is an accepted way of verifying that it won't restart.


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PostPosted: Thu Apr 28, 2011 11:06 am 
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amphead wrote:
Lets say you need to work in a switchboard with an incident energy >40 cal/cm sq. You have properly performed a LOTO at the overcurrent device ahead of this switchboard. Now you must complete the procedure and verify the absence of voltage in the switchboard. What PPE do you wear?

This question was asked in a class I was teaching today and I was unable to give a definitive answer. Made me wonder if I'm qualified to be an instructor in this stuff.


Usually this situation occurs on the secondary of a transformer where the fault current has to be interrupted by the primary fuse or circuit breaker. The IE at the primary will normally be lower and you can de-energize the primary and measure absence of voltage with feasible PPE.

While normally, I would go along with a reduced category for operating the disconnect for LOTO with the doors closed, I don't like this with IE>40 cal/cm2.


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PostPosted: Thu Apr 28, 2011 1:36 pm 
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My comments are directed to the 'non-electrical' LOTO performed by oeprators and technicians. IF you are performing electricial work on the equipment and need to verify no voltage, then yes, you need labelled PPE.


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PostPosted: Thu Apr 28, 2011 2:56 pm 
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Here is one product that should be able to meet the needs of non-electrical people doing isolations...

http://www.redbusbar.com/shop/Voltage-Indicator-LEDs

http://www.graceport.com/medvolt.cfm

http://www.graceport.com/prod_voltage.cfm

I have worked with the Grace lights in the past... That they are available in almost any voltage configurations - 120, 208, 240, 480 volt single and three phase, phase convertors and DC voltages...A client that I worked with installed over 900 of these in their facility to reduce the need for electricians to verify every isolation.

These are wired to the LOAD side of the breaker feeding the piece of equipment to be isolated. When the power is ON there is one light (or set of lights) ON and when the power is switched OFF the light configurations change as per the manufacturer's specification.


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PostPosted: Tue May 03, 2011 7:02 am 
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glen1971 wrote:
Here is one product that should be able to meet the needs of non-electrical people doing isolations...


It needs to be noted that these devices are not adequate to establish an electrically safe work condition. They might suffice if you don't have to open enclosures to expose live parts, but to verify deenergization, you have to test the voltage detector on a known live source before and after verification. This is difficult to do with a panel mounted device.


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PostPosted: Mon Feb 27, 2012 11:38 am 
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jghrist wrote:
It needs to be noted that these devices are not adequate to establish an electrically safe work condition. They might suffice if you don't have to open enclosures to expose live parts, but to verify deenergization, you have to test the voltage detector on a known live source before and after verification. This is difficult to do with a panel mounted device.


To work inside the bucket you need to verify voltage, but to work on the equipment (the motor) you only need to press the run or jog button and verify the motor doesn't start. Correct method is, press jog or run verify motor rotates, lockout bucket (deadfront), press jog or run verify motor doesn't start. No need for electrical PPE as all work is deadfront and not switchgear.

Industry today uses PLC and DCS for motor control. However, we always wire a jog button at the motor directly across the motor contactor just to verify LOTO.


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