It is currently Wed Jul 08, 2020 5:09 am



Post new topic Reply to topic
Author Message
ekstra   ara
 Post subject: Qualified Entrant Training Help Needed
PostPosted: Tue Apr 12, 2016 6:59 am 
Sparks Level
User avatar

Joined: Tue Nov 12, 2013 6:31 am
Posts: 238
Location: Port Huron, Michigan
My facility has decided to create a new level of training that makes the worker know enough to be in an electrical room, even if he isn't qualified to do any electrical work while in the room.

We have to design the training (which I'm guessing will be about two hours in length) and I wondered if anyone had any suggestions or even material for a training of this type.

Thank you.


Top
 Profile Send private message  
Reply with quote  
 Post subject: Re: Qualified Entrant Training Help Needed
PostPosted: Tue Apr 12, 2016 7:59 am 
Plasma Level
User avatar

Joined: Tue Oct 26, 2010 9:08 am
Posts: 2174
Location: North Carolina
Its the same material that applies to the rest of the plant. It shouldn't take 2 hours. OSHA 1910.269 has a lot to say about this for tree trimmers working around overhead lines for source material. I used to have a 20 page powerpoint covering this but I don't have access right now.

1. 95% of electrical inspections are visual. If something doesn't look right, get a qualified person to look at it and don't mess with it.
2. Before operating equipment in particular or even if not, if you see signs of overheating (discoloration), burn marks, liquids including grease and water on or coming out of a panel, excessive heat or noise...get a qualified person to look at it. Stay away.
3. Stay away at least 3'6" from all exposed parts, (10 feet for overhead lines). If you can't get someone there ASAP run barricade tape around it at least 3'6" - 10' away. Explain what exposed means (not guarded, insulated, or isolated) and that exposed status may change for instance if you are on a ladder or manlift vs. walking through the area. May need to list other cases if you have higher voltage levels. Electricians can/should erect barricade tape around energized equipment when they are working on it to let you know when this kind of activity is going on. Unqualified personnel can approach closer only with escort from an electrician.
4. Do not try to rescue something that is being shocked or burned. Shut the power off if you can or get help from qualified personnel. Qualified personnel are trained for emergency release. This is OSHA regulation, not plant preference.
5. If a breaker trips out or a fuse trips, do NOT reset the breaker for two reasons. First this means that there is an ELECTRICAL issue (although the cause may not be electrical). Second breakers are designed for a limited number of trips when an electrical fault occurs. The breaker can be damaged during the trip. I've seen multiple breakers explode that were damaged during a trip. Get an electrician to inspect it first. This is OSHA regulation, NOT plant preference.
6. It is OK to reset an overload relay ONE time if it is known that the motor was overloaded (jammed). After that get an electrician to inspect it. Again, OSHA regulation not plant preference.
7. Motors can only be started a limited number of times. Get the NEMA MG-1 book out and look at whatever your minimum insulation class is, and then there is a chart in NEMA MG-1 that lists the temperature increase per start based on HP. You will find that the smallest motors can be started 3x per hour while the largest ones (over 500 HP) in general can't be started more than once per multiple hours without thermal damage.
8. Include some discussion about working around overhead lines if you have any, conductive ladders and other ladder-like objects such as long sticks of water pipe or conduit, and poking objects and fingers where they don't belong...equipment is designed to protect against INADVERTENT contact, not intentional stupidity. This is just reiterating the "exposed" rule.
9. Explain that while procedures for protecting the general populace are based on avoiding even sensation of being shocked (<5 mA) those for substations (IEEE Std. 80) are designed for survival (<100 mA), and that getting severely shocked (but not killed) is acceptable under abnormal conditions in electrical rooms while not for other areas of the plant.
10. Electrical LOTO falls under OSHA 1910 Subchapter S or various parts of 1910.269, NOT under Subchapter J. Among other things, there are three requirements that are significantly different from Subchapter J. First only qualified personnel can do the "try" (from lock-tag-try). The second is that there is a test for absence of voltage. The third is that grounding must be applied when residual voltages are present or re-energization may occur. Especially when implementing lock boxes, the lockout can be shared (dual-use) between different departments but electrical lockouts in particular go beyond the requirements for others.


Top
 Profile Send private message  
Reply with quote  
 Post subject: Re: Qualified Entrant Training Help Needed
PostPosted: Tue Apr 12, 2016 9:29 am 
Sparks Level
User avatar

Joined: Tue Nov 12, 2013 6:31 am
Posts: 238
Location: Port Huron, Michigan
Thank you. We aren't worried about overhead lines, but the rest is relevant.

Does anyone have any pictures or videos of arc flash incidents I could insert? Just to try to impress on those with a casual approach to electrical rooms that there is really dangerous stuff in the rooms.


Top
 Profile Send private message  
Reply with quote  
 Post subject: Re: Qualified Entrant Training Help Needed
PostPosted: Mon Apr 18, 2016 4:55 am 

Joined: Fri Nov 06, 2015 1:05 am
Posts: 25
Location: Evansville IN
I have been assisting with our fac. switch orders for five years. I have included our on-site fire safety with every switch order. We walk the jobs and review the hazards and equipment. Two resons:1) rescue of team members injuries 2) arc or fire responses.
I use training materials from or ESWP to assist in the awareness training. The cleaning company also has a training program that is 4 hours long. They do an annual refresher. We don't allow anyone Not trained to be unescorted.


Top
 Profile Send private message  
Reply with quote  
 Post subject: Re: Qualified Entrant Training Help Needed
PostPosted: Mon Apr 18, 2016 5:00 am 

Joined: Mon Jun 09, 2014 9:19 am
Posts: 43
Our company created 4 levels of electrical safety for this very reason.

1. Unqualified worker
2. Supervisor, Operators, Qualified Attendants
3. Measurement, Corrosion, Comm techs, Specialists
4. EC Techs

The level you are talking about would be our level 2. We made a CBT that takes about an hour for these guys to watch and a quick 10 question test at the end to keep them honest. These guys do inspections in the electrical rooms, spray for weeds on a substation, back up our EC Techs with safety equipment, etc.. They are taught how to wear PPE if needed and how to select it just like a regular tech would do, but they do not do any type of work! They only back up or inspect.

If you want I can help you with some videos and information for that, I still have the PPT presentation that our CBT was created from.


Top
 Profile Send private message  
Reply with quote  
 Post subject: Re: Qualified Entrant Training Help Needed
PostPosted: Mon Apr 18, 2016 10:51 am 
Plasma Level
User avatar

Joined: Tue Oct 26, 2010 9:08 am
Posts: 2174
Location: North Carolina
I would argue that training on PPE is unnecessary:

1. If it is done in lieu of properly maintaining the equipment then the equipment isn't safe to work on either. If its that dangerous then only qualified personnel should be operating or working on it. If an incident ever occurred and I was a lawyer or an expert witness, I'd eat you alive in court because it becomes tantamount evidence that the employer is maintaining an unsafe work environment and is simply using PPE to avoid making it safe in the first place. It is the same thing as making workers work with any other piece of broken equipment using PPE to avoid eliminating the hazard in the first place.

2. It encourages personnel that are not qualified to take risks that they would otherwise not take.

3. It's a waste of time.


Top
 Profile Send private message  
Reply with quote  
 Post subject: Re: Qualified Entrant Training Help Needed
PostPosted: Mon Apr 18, 2016 11:18 am 

Joined: Mon Nov 23, 2015 9:15 am
Posts: 7
The following is from an OSHA Letter of Interpretation (2002):

Question: Does the OSHA interpretation letter (June 9, 1999) that provided guidance on training non-electrical workers for entry and work within restricted areas such as generating stations and substation also apply for training employees who open
restricted equipment for visual inspection only?

Reply: Yes. As explained in the referenced interpretation letter, employers may train workers as qualified employees for the purpose of entering and performing nonelectrical work within generating stations, substations, manholes, vaults or similar restricted areas.

The employees you identified are assumed to be non-electrically-qualified workers who will open electrical equipment within restricted areas for visual inspection only. Since these visual inspections would require the removal of enclosures or guards, workers could be exposed via proximity to electric equipment that is energized at levels greater than 50 volts. All employees with direct access to the type of equipment or installations covered by 1910.269 must be trained as required by 1910.269(a)(2)(i) and (ii) in order to meet the definition of a qualified person contained in 1910.269(x).

The training outlined in the referenced interpretation letter specifically addresses employees who are not electrical workers but whose work activity would require
exposure to electrical hazards associated with the generation, transmission, or distribution of electrical power. Therefore, the minimum acceptable training for the workers described in your scenario would include the training outlined in the June 1999 letter. Those requirements are provided below for your reference.

1. They must know what is and is not safe to touch in the specific areas they will be entering [paragraph 1910.269(a)(2)(ii)(A)].

2. They must know the maximum voltage of the area [paragraph 1910.269(a)(2)(ii)(B)].

3. They must know the minimum approach distances for the maximum voltage within the area [paragraph 1910.269(a)(2)(ii)(C)].

4. They must be trained in the recognition and proper use of protective equipment that will be used to provide protection for them and in the work practices necessary for performing their specific work assignments within the area [paragraph (a)(2)(ii)(D)]. (Note: Only fully qualified electrical employees may install insulating equipment on energized parts.)

Until these “qualified employees” have demonstrated proficiency in the work practices
involved with their work, they are considered to be employees undergoing on-the-job training and must be under the direct supervision of a qualified person at all times. According to the definition of “qualified employee” the employee must also have demonstrated an ability to perform work safely at his or her level of training. It is expected that an orientation familiarizing the employee with the safety fundamentals given here will be conducted before an employee undergoing training is allowed to enter a restricted area.


Top
 Profile Send private message  
Reply with quote  
 Post subject: Re: Qualified Entrant Training Help Needed
PostPosted: Thu Apr 21, 2016 5:20 am 
Plasma Level
User avatar

Joined: Wed May 07, 2008 5:00 pm
Posts: 822
Location: Rutland, VT
Just something to note is that the OSHA reference above, 1910.269, applies to utilities not industrial facilities.

_________________
Barry Donovan, P.E.
www.workplacesafetysolutions.com


Top
 Profile Send private message  
Reply with quote  
 Post subject: Re: Qualified Entrant Training Help Needed
PostPosted: Thu Apr 21, 2016 8:43 am 
Sparks Level
User avatar

Joined: Tue Nov 12, 2013 6:31 am
Posts: 238
Location: Port Huron, Michigan
wbd wrote:
Just something to note is that the OSHA reference above, 1910.269, applies to utilities not industrial facilities.


Yes, I believe 1910.269 only applies to a small part of our facility, where the steam turbine generators reside. The rest of the mill is under 1910 subpart S.


Top
 Profile Send private message  
Reply with quote  
 Post subject: Re: Qualified Entrant Training Help Needed
PostPosted: Thu Apr 21, 2016 9:55 am 
Plasma Level
User avatar

Joined: Tue Oct 26, 2010 9:08 am
Posts: 2174
Location: North Carolina
wbd wrote:
Just something to note is that the OSHA reference above, 1910.269, applies to utilities not industrial facilities.


Not true at all. But this one has the same problem as OSHA 1910 vs. 1926.

It applies to "generation, transmission, and distribution" facilities. However, there is no clear definition of what these terms mean, especially "distribution". Traditional belief is that 1910.269 applies to utilities and that Subchapter S applies to utilization. However consider three of these examples and how they might apply:
1. An emergency backup generator.
2. A cogen facility that goes offline with loss of incoming utility power (to avoid islanding).
3. A utility-interactive cogen facility that stays online in the event of loss of utility power.
4. Overhead power lines.
5. Transformers and switchgear whose primary purpose is to distribute power to other areas of the plant.
6. MCC's.
7. Panelboards.

In a letter of interpretation, OSHA clearly declared that cogen facilities are definitely generation, transmission, and distribution but that backup generators are not. Thus cases 1-3 are decided.

In prior history utilities used 1910.269 almost exclusively for not only the obvious systems such as substations and power lines but also ignored Subchapter S for such things as lighting panels. Between rulings against utilities and adoption of Annex A, OSHA has made it very clear that utilization rules (Subchapter S) are to be used where ONLY utilization exists, 1910.269 where ONLY generation, transmission, and distribution exist, and a BLEND of both sets where both rules apply. For instance a lighting panel which also has a circuit breaker feeding a battery charger for a substation would be a mix of both utilization and distribution equipment and requires the blended rule set while the switchgear that it powers is strictly distribution and a nearby lighting contactor operating lighting for the facility would fall strictly under Subchapter S.

Thus if the business is a utility, item #5 is 1910.269, #6 is Subchapter S, and item #7 can be either or both. However weak the definitions are though 1910.269 and Subchapter S do not distinguish between types of businesses and neither does OSHA. Thus the same differentiation applies to industrial facilities as it does to utilities.

Finally we come to item 4. In a recent update to 1910.269 (promulgated last year), OSHA updated 1926 to match the requirements of 1910.269 with regards to pole lines. It is very clear from their approach then that especially when the purpose is distribution, pole lines fall under 1910.269.

And getting to the practical issue...so what? What are the major differences?
1. All 1910.269 workers must be qualified workers. This would seem to completely prohibit use of 1910.269 in industrial facilities except for very narrow definitions but distribution equipment is almost always segregated within an industrial facility to begin with and even "unqualified" workers usually receive a minimum level of electrical training today that is appropriate to the tasks that they perform. Thus this is not as big of a stretch as it sounds.
2. The "energized work permit" requirement does not exist under 1910.269. This alone is good reason for considering adoption where equipment is already designed and installed for energized work. This is especially true for operation of fuse cutouts, overhead line equipment, and switchgear.
3. The LOTO requirements are somewhat different. In fact this is the only regulation where OSHA specifically allows tagging out equipment without locks and even allows a centralized control room to perform "virtual lockouts". Thus with today's remotely operated facilities it may be advantageous to consider the different rule set specifically for industrial plants.
4. The "lower cutoff" for incident energy is 2.0 cal/cm2 instead of 1.2 cal/cm2. Also OSHA mandates on arc rated (or FR rated) PPE extend beyond the "lower cutoff". In plants where this is standard PPE there should be no problems adopting OSHA 1910.269. In plants where it is an issue accessing distribution equipment frequently still requires arc rated PPE when doing energized work so the practical effect is minimal.
5. Some terminology differences exist but the function is identical. For instance OSHA 1910.269 refers to the minimum approach distance (MAD) for shock protection. This is the original term used in IEEE 516 which 70E uses for the "restricted approach boundary". There is also a "limited approach boundary" equivalent. However 1910.269 never gives a name to this boundary. The distance for this boundary is identical to the limited approach boundary.

That's pretty much it. I can honestly say from practical experience in a multiple-jurisdictional facility (port rules, FAA rules, MSHA rules, distribution rules, utilization rules) that as intimidating as it may seem, the rule differences are almost trivial in nature.

There are also two rules that trip up workers with a utility background that they will swear on their mother's grave exist when in fact they don't exist at all. The first is that all work must be gloved work, whether or not it includes a hot stick or working on equipment with grounded metal enclosures. This is simply not true and is not an OSHA regulation. In fact at 69 kV and above, gloves are specifically prohibited in the current edition of IEEE 516 because secondary insulation must be rated the same as or better than primary insulation and gloves are not available above about 40 kV.

The second myth is that a visible break disconnect is required for all lockouts and is the only acceptable means of disconnecting power. Circuit breakers are not acceptable. This is also not true and not required by OSHA regulations. What is required is that workers must check to ensure that the blades open IF they are visible but a visible break device itself is not mandatory. It is a working standard among utilities to require a visible break mechanism so that when workers from one utility are working under another utility to repair storm damage, there is no question as to whether or not power has been disconnected.


Top
 Profile Send private message  
Reply with quote  
 Post subject: Re: Qualified Entrant Training Help Needed
PostPosted: Fri Apr 22, 2016 9:14 am 
Arc Level

Joined: Tue Jan 13, 2009 5:00 pm
Posts: 532
Paul,
Please cite the section of 516 that prohibits glove use the way you say. I can only find a recommendation in 4.10.4.1. Thanks.


Top
 Profile Send private message  
Reply with quote  
 Post subject: Re: Qualified Entrant Training Help Needed
PostPosted: Fri Apr 22, 2016 10:20 am 
Plasma Level
User avatar

Joined: Tue Oct 26, 2010 9:08 am
Posts: 2174
Location: North Carolina
Sure.

Whichever insulation system is used this breaks it down into 3 different work methods, listed in 7.2: rubber glove method, live line tool method, and bare hands method. The specific case that I'm referring to is using gloves AND live other tools. See section 4.10.4.1, Worker at ground potential:

"The insulating medium nearest the live parts is considered to be the principal insulation, and the insulating medium nearest the ground is considered to be the secondary insulation.

When two different insulating mediums are used in series, both mediums should be able to withstand the line-to-ground voltage since the division of the voltage gradient across the series combination is not determined. Use of rubber gloves as secondary insulation is not recommended where system voltage dictates an electrical stress beyond the capacity of the rubber gloves."

Dropping down to 7.3.1.13, "...To avoid inadvertent contact with energized conductors or equipment energized at 46 kV or below, appropriately rated rubber gloves and sleeves should be worn. For line-to-line voltages above 46 kV, workers should maintain MADs at all times."

The issue here is that when you have insulation, you have a capacitor (conductor-insulator-conductor). When you have multiple insulation systems, it forms capacitors in series. The trouble is though that how the voltage appears across the insulators depends on various material properties. The voltage is divided up amongst the insulators but not uniformly. The entire voltage may appear across the hot stick for instance or it may be all on the gloves, and that's where the concern is in 4.10.4.1...if you are handling a hot stick at 69 kV with rubber gloves, the 69 kV is partly across the gloves and partly across the hot stick. But it might be 1 kV on the gloves and 68 kV on the hot stick or it might be the reverse with nearly all the voltage drop across the gloves.

7.3.1.13 is stating that rubber gloves should be used as supplementary protection up to the rating of the gloves. "46 kV" is the cutoff for class 4 gloves. If you don't have class 4 gloves available then obviously you'd be underprotected following 7.3.1.13. In that case, 7.3.1.13 is the right concept but the voltage cutoff should be whatever the glove rating is. Above that rating you stay out of the MAD and use some other work method (hot line tools, bare hands), WITHOUT gloves.

Note that in the 1995 edition and earlier, rubber gloves were simply mandated for all voltages that was removed in the 2003 edition. In 2003 there was a very complicated explanation in article 4.10 about primary, secondary, and supplemental insulation when multiple systems are present which made the point above but the confusing explanation made it hard to understand. The 2009 edition deleted all that but the core concept still applies.


Top
 Profile Send private message  
Reply with quote  
 Post subject: Re: Qualified Entrant Training Help Needed
PostPosted: Fri Apr 29, 2016 9:07 am 
Arc Level

Joined: Tue Jan 13, 2009 5:00 pm
Posts: 532
Thanks Paul,

Both sections quoted use the word "should" rather than "shall," so I see no prohibition here.

Here's the situation under current discussion at my place of work. A 69 or 115 kV gang operated disconnect is to be operated. The metallic handle is grounded and bonded to the metallic mat the worker will be standing on when he operates the switch. Some say the extra insulation of rubber gloves can only help the situation, by helping to divert current through the grounds/bonds provided if failure were to occur. Others say the switch should be operated barehanded or with work gloves, since no rubber gloves are rated for the voltage involved. One of us equated this to removing hardhats when working near a helicopter job, since clearly the hardhats are not rated for falling helicopters. What's your take?


Top
 Profile Send private message  
Reply with quote  
 Post subject: Re: Qualified Entrant Training Help Needed
PostPosted: Fri Apr 29, 2016 9:58 am 
Plasma Level
User avatar

Joined: Tue Oct 26, 2010 9:08 am
Posts: 2174
Location: North Carolina
stevenal wrote:
Thanks Paul,

Both sections quoted use the word "should" rather than "shall," so I see no prohibition here.

Here's the situation under current discussion at my place of work. A 69 or 115 kV gang operated disconnect is to be operated. The metallic handle is grounded and bonded to the metallic mat the worker will be standing on when he operates the switch. Some say the extra insulation of rubber gloves can only help the situation, by helping to divert current through the grounds/bonds provided if failure were to occur. Others say the switch should be operated barehanded or with work gloves, since no rubber gloves are rated for the voltage involved. One of us equated this to removing hardhats when working near a helicopter job, since clearly the hardhats are not rated for falling helicopters. What's your take?


OSHA, NFPA 70E, and NESC all refer to IEEE 516 as the definitive reference for shock protection. The "shock protection tables" you see come from that source. There are a couple areas to be aware of but for your purposes I think 7.3.1.13 is the most appropriate:

"When working within the reach or extended reach of conductors or equipment energized at 72.5 kV or below, the conductors or equipment should be covered, if applicable, with protective cover-up equipment rated for the voltage involved. To avoid inadvertent contact with energized conductors or equipment energized at 46 kV or below, appropriately rated rubber gloves and sleeves should be worn. For line-to-line voltages above 46 kV, workers should maintain MADs at all times."

Note that MAD means "restricted approach boundary" in NFPA 70E terminology. The 46 kV cutoff is because there are no rubber gloves rated above 45 kV. In your case rubber gloves are totally useless and offer no protection at all.

Protection is provided by grounding. See IEEE Standard 80 for substation grounding design which speaks a lot more to the idea of workers being grounded with a relatively low resistance path to ground as opposed to becoming "floating" objects (not really grounded or energized) where shock becomes a serious hazard. The ground grid under the substation, all the bonding to it, and even the gravel covering the substation yard are all integral to the design. It is designed based on formulas to maintain step and touch voltages to acceptable maximums. That's the reason for the bonding you are referring to. Note that IEEE 80 standard grounding is not what most people expect. Whereas low voltage and "general public" protection is to avoid even the sensation of being shocked, grounding in a substation allows for shocks to occur as long as they are not fatal.

If you are really worried about it, you can get an insulating (fiberglass) section that you can install in the middle of the operator (pipe) coming down from the switch. I've bought these from A.B. Chance, Siemens, and Cooper before. Since the diameter of the pipe is pretty standardized you should be able to easily retrofit if you're not winning the argument.


Top
 Profile Send private message  
Reply with quote  
 Post subject: Re: Qualified Entrant Training Help Needed
PostPosted: Wed May 04, 2016 10:50 am 
Arc Level

Joined: Tue Jan 13, 2009 5:00 pm
Posts: 532
The switches in question are attached to overhead substation bus. The worker in this situation is well outside the MAD. I disagree that gloves are worthless, since by holding a grounded/bonded handle while standing on a grounded/bonded mat; there is no way there will ever be line to ground voltage across the worker from these contact points. The highest possible voltage would be the drop across the bond wire.

I've seen insulating sections in pipes as you describe, but they always are very small. By the same argument used for the gloves, these should be fully rated 115 kV insulators with sheds. The ones I've seen are not.


Top
 Profile Send private message  
Reply with quote  
 Post subject: Re: Qualified Entrant Training Help Needed
PostPosted: Wed May 04, 2016 10:57 am 
Plasma Level
User avatar

Joined: Wed May 07, 2008 5:00 pm
Posts: 822
Location: Rutland, VT
From my 30 plus years in utilities, it was always standard practice to use rubber gloves when operating gang operated switches whether in a sub or out on lines. We were also trained never to let the handle come in contact with your body.

Other standard PPE was a hardhat and safety glasses. Now the standard PPE would also include arc rated clothing.

_________________
Barry Donovan, P.E.
www.workplacesafetysolutions.com


Top
 Profile Send private message  
Reply with quote  
 Post subject: Re: Qualified Entrant Training Help Needed
PostPosted: Wed May 04, 2016 4:12 pm 
Plasma Level
User avatar

Joined: Tue Oct 26, 2010 9:08 am
Posts: 2174
Location: North Carolina
stevenal wrote:
I've seen insulating sections in pipes as you describe, but they always are very small. By the same argument used for the gloves, these should be fully rated 115 kV insulators with sheds. The ones I've seen are not.


I didn't make up the rule. I articulated the standard. If indeed the entire space about the worker has no voltage on it, then gloves don't hurt but also don't help anything either.

At 115 kV and higher (the substation I was responsible for at these voltages was 230 kV), on a pole typically you will use suspension insulators or V-strings where the insulators are modular and strung together. Equipment bushings are the only "insulator" you will find that is a single piece. They are frequently hollow or oil filled. And I misspoke and you are correct. The insulating sections for operators are going to be roughly at "glove rating level" (35 kV and lower). It isn't hard to figure out how to make an insulating section that is big enough...just think about the specification for a hot stick (100 kV per foot) and imagine how long of a glazed fiberglass shaft would be necessary to achieve the required insulation (about 1.5 feet), from an insulation point of view. Since the critical flashover distance is much longer the driving requirement is going to be how long the shaft needs to be to avoid a flashover rather than insulating properties. Even a wood beam could do it if designed properly out of hardwood. The CFD for wood beams is the same as it is for crossarms.

As to not seeing this rule from IEEE 516 before...I'm not surprised. The older versions don't mention it. Then I think the previous edition (2003?) specifically required rubber gloves for basically everything and was understandably met with a lot of resistance. The latest (2009) version corrected these errors since there was push back about the differences in voltage (no such thing as "115 kV rated gloves). But this isn't the first time that the work rules surrounding energized work have changed drastically in terms of shock protection. How many utilities are still wrestling with the concept of equipotential grounding? I can tell you for sure based on the opinions of several employees of the largest utility in the U.S. that they were trained that equipotential or work site grounding means at least one ground at the job site but doesn't mean that redundant grounds are not acceptable. This is of course the direct opposite of the principles behind equipotential grounding since it opens the door to induced currents from nearby lines but that's how the utility in question is interpreting the new requirement.


Top
 Profile Send private message  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 17 posts ] 

All times are UTC - 7 hours


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  
© 2019 Arcflash Forum / Brainfiller, Inc. | P.O. Box 12024 | Scottsdale, AZ 85267 USA | 800-874-8883