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 Post subject: Qualified electrical employees and tasks
PostPosted: Mon Mar 19, 2012 2:29 pm 

Joined: Mon Mar 19, 2012 1:21 pm
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Do you have a list of tasks that your qualified employees are qualified to perform?

Is that list short (<10) or large (20-30-50+)?

I'm having trouble trying to figure out if I should break the tasks that an industrial electrician would likely perform into a few easily managable categories (say 5 categories), or if we should have less "grouping" of tasks and have a longer list of very specific items/tasks. For example, I could have a "task" such as: "new equipment installation" and within that task could include everything from the initial sizing of conductors, to wiring methods right up to turning the machine on for the first time. Or, I could break this one task down into 10 or 20 smaller steps and document/verify that the employee is doing each step safely and correctly.

At some point having a super long list of tasks becomes impractical. At some point. But on the flipside, the more you group tasks together perhaps the less detailed you are and the more open to risk/liability you are?

If I'm approaching this the wrong way, please tell me. But it seems to me that the trend in electrical safety is moving more towards having specific tasks that someone is approved or qualified to do, and away from having guys that are just "qualified electricians" who receive re-training every 1-3 years. My company currently does not have it broken down by task and I'm looking for some help.

Thanks,
RB


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PostPosted: Wed Mar 21, 2012 3:56 pm 
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We have basically 5 categories: switching (production), HVAC technician, low voltage electrician, medium voltage electrician, and lineman. Although it would seem like those categories are additive, they are not. Some operations also have instrumentation technicians as separate from electricians. Even in the line crew, they separate ground men from linemen.


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PostPosted: Wed Mar 21, 2012 8:21 pm 
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There are also different degrees of experience amongst journeyman electricians...

While in school for my fourth year a guy in class asked me, "How many houses have you ever wired?". "None" I replied. "How do you know anything?" he asked, kinda laughing.. I asked, "How many gas plants have you ever built?". "None" he said. I said, "How do you know anything? Every plant I have been on has a service, lights, receptacles and a few 'switches'." He thought for a minute and asked, "Well what is the biggest motor you have ever hooked up?" I said, "That is not a fair question.. What is the biggest you have done?" "10 horsepower." He replied. He almost fell over when I told him mine was 27,000 hp...


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PostPosted: Thu Mar 22, 2012 3:42 am 
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Voltage probably plays the biggest factor in dividing up qualifications because there are major differences in work methods at various voltages. Below 600 V, the work methods are pretty uniform even if the equipment isn't across the residential/commercial/industrial spectrum.

At least based on work methods (and simple physics) alone, there is a huge difference between say <240 VAC, one transformer, 125 kVA or less (although this rule may change in the future), from there up to around 600-1000 VAC (jurisdiction dependent), 1 kV up to around 2.5 kV, 2.5 kV to 10 kV, 10 kV-35 kV, 35 kV-69 kV, and 69 kV+:

Above 240 V, energized work requires rubber gloves and arc flash PPE. Some plants still allow insulated tools though up to 1000 V (tool rating). This is the point where direct contact is no longer a necessity for a shock (it can reach out and bite you). The prohibited approach boundary comes into play.
At around 600-1000 VAC, various "high voltage" rules kick in. The code rules for all jurisdictions change to disallow access by unqualified folks in pretty much any capacity.
Below around 2-3 kV, partial discharge realistically is almost impossible, and unshielded cable is still available up to 2 kV.
From 2.5 kV up to around 10 kV, stress cones should be used but in practice the impact is small and some operations (notably mining) tend towards not using them. Above this point, you flat out can't get away with not using them anymore. Rubber glove, line-line, bare hands, or hot stick work becomes required.
At 35 kV, we reach the end of the road for rubber glove work, and I'm not aware of vacuum bottles above this point. 35 kV is generally considered the cutoff for vacuum technology.
At 69 kV, a second shield has to be added. At this point as well, live-line, bare hands work is becoming increasingly popular.


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PostPosted: Thu Mar 22, 2012 8:18 pm 
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From my experience Paul, unshielded cables to 5 kv are widely used in the Oil and Gas in Alberta. With the unshielded cables, stress cones aren't widely used at that level. I think I have only seen one place (maybe 2) that they used shielded cables, and stress cones.

One company I work with went to the trouble of buying 2 FULL sets of 1 kv insulated tools (sockets, wrenches, screwdrivers, etc)... When I heard that they purchased them, I asked "What on earth for??" They said "To retorque MCC buss bars and lugs without an outtage.." I replied "Who is gonna ok my permit for me to work on the LINE side of 1,000 amp breaker HOT? And who is gonna do that?? There is nothing here that can't be shutdown. All you need them for is when you are replacing batteries.." They have never been used yet....


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PostPosted: Fri Mar 23, 2012 4:07 pm 
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I agree about oil & gas. I have personally been to mines in Fort McMurray and Saskatchewan (potash) so I have at least some cursory understanding. We don't use stress cones either on SHD cable since it only lasts for about 10 years in typical use anyways (except the stuff right behind a shovel...you'll be doing good to keep it around that long).

When they changed the rules in the U.S. and started requiring shielded cable above 2 kV, unless you really hunt around for it, it is getting nearly impossible to even get it. The rule is especially troublesome with it comes to CT's, PT's, and CPT's on the inside of equipment where you typically don't use shielded cable in the first place.

And I have found a use for the insulated tools. If you follow 70E to the letter and want to avoid a glove fiend trying to make everyone wear rubber gloves for 120 VAC work, the rule says "avoid contact" and I've successfully fended them off by using insulated tools instead. Keep in mind though that this really means using meter probes and occasionally using a screwdriver as a pry bar to move wire aside for measurements.

Very occasionally taking lighting panel breakers on and off the bus which usually has one screw that has to be tightened down and is technically live work. In the latter case, I read it this way. Is the shock hazard greater or the same compared to throwing the breaker and testing for absence of voltage? Is the arc flash hazard the same or greater for throwing the breaker and testing for absence of voltage? Then there's all the ancillary things that can happen as you increase the hazards for everyone else in the process of shutting down and starting up especially if the lighting panel contains control circuit power. This is NOT the same as the "continuous industrial process" argument that has been repeatedly misapplied. This is making an honest, real assessment of the hazards of two alternative sets of work tasks.

Generally speaking as soon as the hazard of doing the work energized becomes greater than the hazard of de-energizing itself, the scales tip very quickly in favor of de-energizing.


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PostPosted: Tue Apr 03, 2012 8:59 am 

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The challenge that I have isn't really voltage dependant, at least not to the types of voltages you guys are discussing.

We have industrial manufacturing plants where 99% of the work is on 480 volt and less equipment. Actually for most of our plants it's probably 100% (if "high voltage" work, above 600 is needed, we would use outside contractors). We have some small plants in some rural locations with maybe <100 employees, maybe 5 "maintenance" employees and just 1 "electrician". We have a lot of plants that want their "maintenance" guys to be able to do some basic troubleshooting of equipment, use a volt meter, perhaps change a fuse or sensor/relay and then if there is an electrical problem they'd call the electrician and have him fix it. If it was something simple like a fuse, the "maintenance" guy would just replace it.

One of the problems that we've had is that we put together a huge training program, including a very long written test, for all the maintenance guys to essentially "train them up". And the problem we have is that many of the guys struggle to pass the test, and most of the training materials don't really correlate to what these guys do in the field. I mean, we have them doing "power" calculations with calculators in the class.

Is there a better way to "qualify" people for tasks such as voltage testing, fuse/relay/sensor testing and replacement? Rather than trying to turn them into quasi-electricians?


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PostPosted: Tue Apr 03, 2012 9:46 am 
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I guess my first question is have your plants completed an arc flash analysis or are you just using the tables? Don't be fooled by the voltages, having Ei's >40cal/cm2 is very common on 480V systems and most industrial plants will have closer to 100 cal/cm2 areas in thier "blind spots", or the secondary of a MV/LV transfomer up to the feeder breakers in the 480V switchgear.

You can train people on a specific task and qualify them to perform that specific task but your safety program has to make it very clear who is qualified to do what. The problem is even a simple task like replacing a fuse or using a volt meter can expose those people to dangerous arc flash levels.


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PostPosted: Tue Apr 03, 2012 11:47 am 

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Yes, we have done the arc flash analysis at all of our plants.

And yes, we do have several pieces of equipment rated at category 4 or higher. I just pulled a binder for one plant and we had 9 pieces of equipment that were rated "dangerous" or >40 cal/cm2. But I'm confident our guys aren't accessing or working on these pieces of equipment. I'm pretty confident that in general our qualified employees are following the arc flash label requirements.

The challenge I have Zog is what you say in your last paragraph: "...but your safety program has to make it very clear who is qualified to do what.".

We currently don't have that documented very well. Guys are just "qualified" or they're not. I suppose what I need to do is generate a list of tasks? And then go employee by employee and say who is qualified to do what? Should I make the list very specific tasks, or should I group tasks together?


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PostPosted: Tue Apr 03, 2012 1:26 pm 
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Article 110.2 gives some guidance on this but does nto get to specific, because each facility will have different hazards, equipment, and job descriptions.

One common one is "Operators" at a power plant. The only thing close to electrical work some of them do is operating and racking of specific breakers, so they get training specific to that breaker including the construction and operation of that breaker type, interlocks, procedures, and PPE requirements.

Two of the most overlooked tasks are using a voltmeter and resetting breakers or replacing fuses. There are a lot of things to consider for what seems like a simple task but improper voltmeter use is one of the most common electrical injury causes.

Replacing fuses or resetting breakers has some specific rules:

OSHA 1910.334 (b)(2) "Reclosing circuits after protective device operation." After a circuit is deenergizedby a circuit protective device, the circuit protective device, the circuit may notbe manually reenergized until it has been determined that the equipment andcircuit can be safely energized. The repetitive manual reclosing of circuit breakersor reenergizing circuits through replaced fuses is prohibited.

Note: When it can be determined from the design of the circuit and theovercurrent devices involved that the automatic operation of a device wascaused by an overload rather than a fault condition, no examination of the circuitor connected equipment is needed before the circuit is reenergized.

So if there is no indication of why the fuse blew, or the breaker tripped you have assume it was not an overload, so the circuit needs to be verified to be safe to re-energize which often means getting out a megger and/or troubleshooting, which is not something you want an assembly line worker to be doing.


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PostPosted: Tue Apr 03, 2012 2:01 pm 

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I agree, it sounds simple but there are many things that could go wrong. And I'm familiar with the OSHA reg and why it's not safe to continually reset circuit breakers (or replace fuses) that fail.


Let me create a fictional scenario and then ask about what the typical training, qualification and documentation process might entail.

Disclaimer - I'm a safety guy and not an electrician or electrical engineer. Please be gentle, I come in peace :)

Problem: Employee calls his supervisor and says he has a mixer in a tank that won't turn on, perhaps the motor is dead.

Supervisor calls maintenance and a maintenance guy goes over to check it out. I assume this is a scenario where the maintenance guy could reasonably be expected to use a voltmeter to see if the motor is "fried". Let's assume no upstream circuit breakers or fuses were tripped/blown.

So, skipping ahead to the documentation part of "qualifying" a maintenance guy to do this type of work. We can:
A) provide electrical training in a classroom scenario that covers a wide variety of topics but such things as electrical basics, OSHA rules & regs, NEC rules & regs, safety & health risks of electricity, how to distinguish live parts from non-live, etc...
B) provide arc flash training in a classroom scenario (I separate this out because it is a separate training course for us)
C) Perform hands on training, or verify through auditing or inspection of the workplace (by watching him do it and perhaps quizzing him with questions and scenarios), that the employee knows how to safely use a voltmeter for this type of troubleshooting situation.
D) Document this employee is qualified to use a voltmeter to troubleshoot equipment (say 480 volt or lower for sake of debate)


I know I am generalizing a bit. And this is just one task. But is this a reasonable and typical approach to "qualifying" someone to do a task that you know they will be asked to do? Am I missing a key step?


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PostPosted: Wed Apr 04, 2012 5:59 am 
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Your training for the senario sounds about right but I would recommend limiting what they can work on to a certian PPE/Ei/HRC level, not voltage. You have to provide the PPE required for the job so maybe limit your "non-qualified" guys to HRC 0 or 1 equipment. Which should not be a problem for most equipment on the production floor.


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PostPosted: Wed Apr 04, 2012 6:40 am 

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Thanks for the feedback Mr. Zog :)

I don't know if we're splitting hairs here but I would document my maintenance guy in this scenario as a "qualified" electrical employee. Not "non-qualified". And I would document that he's qualified to do certain tasks only, and that he's only allowed to work on HRC 0-1.

Typically at our plants we would have 1-2 guys that I would consider more of a true electrician. These guys would obviously also be "qualified" but I would have a longer list of tasks that they are approved to do. Also they would likely be allowed to work on equipment up to HRC 2 or 3 since we've purchased the gear for them to do so.

I assume it's OK for me to consider my maintenance guy "qualified" given the training and hands-on evaluation that I've laid out above?


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PostPosted: Wed Apr 04, 2012 6:45 am 

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racineboxer wrote:
Do you have a list of tasks that your qualified employees are qualified to perform?

At some point having a super long list of tasks becomes impractical....


Excellent point- simply starting a list of tasks is a great idea- it gives significant guidance to your intended definition of 'qualified'.
A long list may be more precise, but grouping into categories makes the information more accessible-

A firearm analogy- almost any gun manual will have a laundry list of rules- 20-40 is not uncommon.

But the best teachers (Ayoob, Cooper, et. al.) focus on a few basics- never let the muzzle point at anything you are not willing to destroy, never touch the trigger until you are ready to fire, always be sure of the target, and what is behind the target- (how far will the projectile travel). These are greatly effective because they are easily memorized, and the safety mechanisms are redundant to a degree.

I try to follow this pattern in anything i have to be concerned with safety (flying, chemistry, engineering, etc.).

john


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PostPosted: Fri Sep 21, 2012 5:00 am 

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Yes the task varies in its approach the scale of plant or the voltage of the plant you are working for is it enough or not. Moreover the strength of your staff and safety features you have for them or so on.


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PostPosted: Fri Sep 21, 2012 5:20 am 
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glen1971 wrote:
From my experience Paul, unshielded cables to 5 kv are widely used in the Oil and Gas in Alberta. With the unshielded cables, stress cones aren't widely used at that level. I think I have only seen one place (maybe 2) that they used shielded cables, and stress cones.


Unfortunately, in the U.S. it is actually difficult to actually purchase unshielded cable even for places where it is definitely not required such as leads to PT's and transformer cables inside cabinetry. Not impossible but difficult to find anything over 2 kV these days. Of course it is also difficult to find CSA "Tech 90" and "Tech HV" even though those are commonly used all over Canada whereas in the U.S. typically your choices are conduit or TC-ER.

Quote:
One company I work with went to the trouble of buying 2 FULL sets of 1 kv insulated tools (sockets, wrenches, screwdrivers, etc)... When I heard that they purchased them, I asked "What on earth for??" They said "To retorque MCC buss bars and lugs without an outtage.." I replied "Who is gonna ok my permit for me to work on the LINE side of 1,000 amp breaker HOT? And who is gonna do that?? There is nothing here that can't be shutdown. All you need them for is when you are replacing batteries.." They have never been used yet....


OK, now let's consider 120/240 VAC equipment such as terminal blocks for lighting panels or PLC's. From an arc flash point of view there is no major hazard. From a shock point of view the danger is the equipment NEXT to the terminal you are accessing. The terminal itself is "dead" but you are well within the limited approach boundary. And although the chart says "avoid contact" for all practical purposes the only way to avoid this is to use tools that are insulated sufficiently to prevent phase to phase contact. In many industries (especially automotive) just to avoid the issue altogether they are going to putting the "high voltage" (120 V) stuff in an isolated cainet including 24 VDC power supplies and using only 24 VDC in the PLC cabinets for this reason. Lighting panels do not benefit from this, and MCC's similarly do not benefit.


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