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 Post subject: Clarification on 110.2(C)(1) and 110.3(C)
PostPosted: Thu May 26, 2016 9:27 am 
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Have two questions that need to be addressed from the Safety Manager of California Steel in San Bernardino CA

110.2 (C) (1) Contact Release. Employees exposed to shock hazards shall be trained in methods of safe release of victims from contact with exposed energized electrical conductors or circuit parts. Refresher training shall occur annually.
*So the way I read this is anybody that goes into a motor room that might bypass a restricted or limited approach boundary. But in our case we have exposed buss work in the main motor room and #3 control house, so this should also be covered.

110.3 (C) Documentation. Where the host employer has knowledge of hazards covered by this standard that are related to the contract employer's work, there shall be a documented meeting between the host employer and the contract employer.
*So what I am thinking is we could point to Google Calendar and that would document a meeting, but not necessarily the actual items discussed. Now the problem would be who is going to take the notes?


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 Post subject: Re: Clarification on 110.2(C)(1) and 110.3(C)
PostPosted: Thu May 26, 2016 10:22 am 
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Laura wrote:
Have two questions that need to be addressed from the Safety Manager of California Steel in San Bernardino CA

110.2 (C) (1) Contact Release. Employees exposed to shock hazards shall be trained in methods of safe release of victims from contact with exposed energized electrical conductors or circuit parts. Refresher training shall occur annually.
*So the way I read this is anybody that goes into a motor room that might bypass a restricted or limited approach boundary. But in our case we have exposed buss work in the main motor room and #3 control house, so this should also be covered.

110.3 (C) Documentation. Where the host employer has knowledge of hazards covered by this standard that are related to the contract employer's work, there shall be a documented meeting between the host employer and the contract employer.
*So what I am thinking is we could point to Google Calendar and that would document a meeting, but not necessarily the actual items discussed. Now the problem would be who is going to take the notes?


These don't look like questions. Item #1 refers only to anyone crossing a restricted approach boundary and here's why. The limited approach boundary applies only to unqualified employees and is the minimum approach distance for them with the minor exception of being escorted by a qualified employee. They are not trained in the use of shock protection PPE and are simply not exposed to shock hazards. Their training is limited to recognizing that a hazard exists and to maintain distance to avoid it altogether. Qualified employees on the other hand are trained to work within the restricted approach boundary...full contact with proper PPE is allowed. Training includes the use of insulated tools which in fact actually do shock the employee during normal operation although the shock is so minor in most cases (microamps) that it is not perceptible.

Second, the definition of exposed is that it is not insulated, guarded, or isolated. Overhead bus work is isolated at least up until the point that someone gets a ladder out and climbs up. The general concept of the approach boundaries is that they are 360 degree spheres. However when it comes to the limited approach boundary this does not always hold true. For instance OSHA states that the boundary is 10 feet for travelling under a power line but recognizes that strictly tramming equipment through the area reduces the boundary to 4 feet (matching the nonmovable standard). Various standards such as NESC allow bare overhead bus work down to as low as only about 8.5 feet off the ground, certainly closer than a 360 degree, 3'6" sphere would allow for assuming the average worker is around 5.5-6 feet tall. Previous versions of 70E gave a "prohibited approach boundary" which is essentially the limited approach boundary after removing the adder for inadvertent movement (from the original standard, IEEE 516). It would make more sense from a vertical overhead distance to consider the prohibited approach boundary plus maximum reach of an employee (generally considered 8 feet) which matches the few standards that exist for this situation.

Second the purpose of the meeting for contractors is to convey information. There is a lot of information such as specifically incident energy values and more specifically any particular company's interpretation of 70E (since it is so open to interpretation) that vary from one company to another. Items that would need to be discussed for instance is that OSHA leaves every company open to how they designate lockout locks as distinct from all other locks, what the incident energy values are in an area, whether or not electrical equipment is considered in good working order and thus can be operated without PPE or is maintained in an inherently dangerous condition, emergency contact information and plant procedures for ambulance, etc. Most of this is standard practice at most companies to pass on this type of information to the contractor.


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 Post subject: Re: Clarification on 110.2(C)(1) and 110.3(C)
PostPosted: Sun May 29, 2016 6:37 am 
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Small error on my part. IEEE 516 calculates the distance at which a shock is possible and then adds an inadvertent movement adder to that number to arrive at the minimum approach distance (MAD). They used to overcomplicate it with a variation for tools, working from a bucket truck, from a helicopter, etc. NFPA 70E renamed MAD to restricted approach boundary and the base (no movement) distance as the prohibited approach boundary. All of these boundaries by the way come from a standard for overhead lines. The third boundary (limited) exists for overhead lines and is 10 feet plus some additional distance when the voltage reaches a point that it has to be moved out. The 3'6" boundary has existed for a long time and is also somewhat vague in origin. Both exist for distribution equipment under OSHA regulations but are never named. Sometimes only the 10 foot boundary appears without a distance adder for high voltage. So for instance NESC has an unnamed boundary for elevating exposed bushings that is the MAD plus 6 feet without the movement adder and is the standard for clearance for distribution equipment such as overhead bus work. Where equipment is isolated, insulated, or guarded, see the definitions in 70E where the shock hazard boundaries do NOT exist. Otherwise for instance there would be a 3'6" boundary around extension cords and someone would need to wear rubber voltage rated gloves to push the power button on a desktop PC. Just because energized metal is or is not visible does not make it exposed. For the reverse case consider a meter mounted on a sheet metal panel that is open on the back side, something common on older pneumatic and hydraulic equipment. This is guarded. It is not exposed normally since it is protected against accidental contact but if someone reaches behind the sheet metal panel, it becomes exposed. Similarly most breakers, relays, etc., have recessed lugs that are guarded but become exposed when an employee inserts a screwdriver or meter probes. But it is not exposed if the meter probes or screwdriver are insulated since once again it is protected from accidental contact. And no, 5 layers of vinyl electrical tape around the screwdriver as makeshift insulation does not count.


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 Post subject: Re: Clarification on 110.2(C)(1) and 110.3(C)
PostPosted: Sun May 29, 2016 5:41 pm 
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Thank you for this information


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 Post subject: Re: Clarification on 110.2(C)(1) and 110.3(C)
PostPosted: Wed Jun 22, 2016 10:54 am 
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Paul, I was the one that forwarded these questions to Laura, if I may I'd like to ask a little more on these topics. When it comes to Contact Release I understand what your are saying (and if I'm not please correct me) that only those who will be crossing into the restricted approach need to worry about training, but to be more specific what exactly does the annual training need to cover as pertaining to this section?

The second question was to see if there is a minimum amount of recording required for a meeting between a contractor and a host employer as to what is covered in a meeting about known hazards and which entity would be responsible for that paperwork.


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 Post subject: Re: Clarification on 110.2(C)(1) and 110.3(C)
PostPosted: Thu Jun 23, 2016 6:50 am 
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MFelts477 wrote:
Paul, I was the one that forwarded these questions to Laura, if I may I'd like to ask a little more on these topics. When it comes to Contact Release I understand what your are saying (and if I'm not please correct me) that only those who will be crossing into the restricted approach need to worry about training, but to be more specific what exactly does the annual training need to cover as pertaining to this section?


There is one and only one method documented in 70E as a correct method for contact release and that would obviously be shutting off power (LOTO) since at that point, the victim is energized and shock protection boundaries apply. If all the procedures in 70E are followed then we should never be in that situation anyways but in the real world obviously things can happen. 70E itself is silent in any other way on exactly what "emergency release" or "contact release" training should entail and it's not mentioned in OSHA regulations either so you are on your own to define what it means.

The training that I've received (never done it) for contact release (used to be called "emergency release") starts with shutting off power and then divulges into a discussion about not becoming a victim. After this point the instructor made it clear that everything else is unofficial and merely a discussion because we're no longer within the realm of rules, policies, and regulations and instead we're into the realm of choosing the best of a list of bad choices. It followed by suggestions about what you can do in terms of make shift tools and equipment. Rescue hooks which are available on the market are discussed but also it is pointed out that again...it's an emergency situation and why would you expect to have one around for these situations. Some discussion about escaping from an energized vehicle (hopping/shuffling technique to avoid GPR) and similar emergency procedures typically discussed for linemen were also covered.

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The second question was to see if there is a minimum amount of recording required for a meeting between a contractor and a host employer as to what is covered in a meeting about known hazards and which entity would be responsible for that paperwork.


There is no specific form. The issue is the due diligence standard, not a compliance standard.

Think about the consequences. If it ever comes into question about why a contractor did not follow a procedure, the host e
employer (and contractor) need the paperwork to show that it was brought to attention. It is something of a legal defense to claim that a contractor did something on their own but especially in states where contributory negligence or partial damages are allowable, it is very important to document that the responsibility was passed off for both sides...the contractor may claim they were not informed of a hazard and the host employer may claim the contractor went off and did something on their own without knowledge/permission. Without documentation, it can be difficult to prove either one. OSHA has also fined host employers for incidents that occurred on their site and "the contractor did it" does not count as a defense. The host employer is responsible for conditions on their site. The contractor is responsible for their equipment and procedures but when the two worlds collide, OSHA can go after either one so it is critical that both sides have documentation to avoid fines and/or losing a court battle especially if an employee is seriously injured and the workman's compensation claims reach into millions of dollars which is typically where they end up at with survivors or serious shock and arc flash injuries.

Getting away from due diligence, the purpose of the meeting is very simple. The contractor has their rules and procedures and the host employer has theirs. Also the host employer probably should have a better grasp on hazards and risks compared with the contractor. However 70E (among other rules) has a lot of area that is subject to interpretation. For instance the contractor may implement the table method in 70E if they don't have access to more refined (IEEE 1584) data if they do anything at all. An agreement must be made as to how to handle this. Especially for site-specific definitions, there is likely to be some differences in PPE. OSHA specifies that lockout locks must be uniquely identifiable from all other types of locks. Some sites use a specific make/model of lock and others identify it by a color or some other kind of marking. The way that the OSHA regulation in 1910.137 is written it is almost impossible for the contractor to not use the same procedure as the site. For portable cords OSHA allows for either use of doubly-insulated tools and equipment, or use of GFCI's, or quarterly inspections of equipment especially cords. MSHA requires annual ground testing on all tools, cords, and equipment. Both require inspections before use and since MSHA will dig through your tool crib and cite on equipment that isn't even in use on the grounds that it was obviously defective during the last use, you have to inspect before putting it away, too. So in most cases most operations adopt some sort of color coded tape marking system to track whether or not extension cords in particular have been inspected quarterly or annually. The contractor's color coding system and the site's color coding system and/or requirements will vary and it is usually best if everyone is using the same policies and procedures (render unto Caesar what is Caesar's).

This is for first time meetings or for large jobs, especially when for instance its a construction site that is separated from the rest of the facility. For routine/regular work where the same contractors are coming on site for repeat visits the extent of the meeting should be the same material that is typically used in a JSA/JHA which is to identify the hazards for a specific site and location since policy and procedure differences have been previously ironed out.

This is where a safety professional can really help. They've been through this with the general content many times. When it comes to 70E you can pretty much tell where the problems will be...anything where there are questions or interpretation decisions that had to be made in terms of implementation are subject to different interpretations and thus different implementations. As an example I'm NOT a proponent of automatically requiring PPE for all electrical tasks regardless of whether there is a risk or not although others are such as operating disconnects and circuit breakers on equipment that is not showing any signs of abnormal operation. I'm also NOT a proponent of the so-called "no energized work" policies that are clearly ridiculous since electrical LOTO requires testing for absence of voltage which is energized work. Based on information that I have I don't believe you can categorically eliminate PPE requirements for all work at 250 V or less but at the same time there is a lot of this work that can be done safely without PPE. I think that gloving up to use a multimeter on 120 VAC control circuits is similarly silly when hazards are minimal, as is using gloves with hot sticks and even to operate disconnect handles. All of these are examples of interpretational differences. However all contractors and all sites have also approached these decisions and come to different conclusions that may be in agreement or disagreement with my opinion and thus they will have different policies and procedures. They may have a procedure where contractors can implement whatever procedures they follow, or they may require contractors to match plant procedures as a minimum standard, exceeding it where contractor policies are more strict. If you have a decent plant policy/procedure for electrical it only requires both of you reading each other's standards to identify the differences and iron them out.

At least that's the approach I've used from both sides of the table for both small (1 or 2 person jobs lasting less than a day) and very large (hundreds of people spanning multiple years) jobs.

If you need specific help and not just general statements, PM me.


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 Post subject: Re: Clarification on 110.2(C)(1) and 110.3(C)
PostPosted: Thu Jun 23, 2016 10:56 am 
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PaulEngr wrote:


Second, the definition of exposed is that it is not insulated, guarded, or isolated. Overhead bus work is isolated at least up until the point that someone gets a ladder out and climbs up.


Interesting definition. I would consider overhead bus work to be very well insulated by the insulators that support it and the air the surrounds it. (I like those self healing insulation mediums) Therefore the overhead bus work is never exposed by that definition, even when someone climbs up. Perhaps we should get that definition changed on the next go around. I agree that if not isolated or guarded, the bus work should be considered to be exposed.


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 Post subject: Re: Clarification on 110.2(C)(1) and 110.3(C)
PostPosted: Thu Jun 23, 2016 11:50 am 
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stevenal wrote:
PaulEngr wrote:


Second, the definition of exposed is that it is not insulated, guarded, or isolated. Overhead bus work is isolated at least up until the point that someone gets a ladder out and climbs up.


Interesting definition. I would consider overhead bus work to be very well insulated by the insulators that support it and the air the surrounds it. (I like those self healing insulation mediums) Therefore the overhead bus work is never exposed by that definition, even when someone climbs up. Perhaps we should get that definition changed on the next go around. I agree that if not isolated or guarded, the bus work should be considered to be exposed.


You're right but I never thought about it that way. Below 2 kV we could probably change the definition to solidly insulated systems without much trouble but once we get above 2 kV, all kinds of mixtures of gas, liquids, and solids apply, some with virtually no surface current and others with current present. And then we get into the fact that system voltage may no longer be the appropriate metric. For instance there is the capacitive tap on an elbow connector on a 35.5 kV medium voltage shielded cable. The voltage at that point is 35.4 kV so does it require class 3 or 4 gloves and hot sticks? No because the current is microamps.


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 Post subject: Re: Clarification on 110.2(C)(1) and 110.3(C)
PostPosted: Fri Jun 24, 2016 6:16 am 
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So from this discussion the way I am interpreting 110.2 (C) (1) is, first off we no longer hand the apprentice a 4x4 for contact release. Second, this should be a topic covered with qualified personnel and should be included in the JHA whenever someone is going to be in Restricted Approach Boundary. That there is no real "approved" method of contact release, but it should be addressed on a case by case basis with the goal of the procedure laid out to ensure, as you said Paul, that no one else becomes a victim. That if the topic of Contact Release is discussed at least once a year during a regular safety meeting that should meet the requirement of 110.2(C)(1) because you have informed all of your qualified people of how to plan accordingly.

Next as far as the meetings go, it is just best for everyone to meet, have notes of all topics covered and both sides be responsible for keeping those notes for further reference.


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 Post subject: Re: Clarification on 110.2(C)(1) and 110.3(C)
PostPosted: Fri Jun 24, 2016 8:42 am 
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MFelts477 wrote:
So from this discussion the way I am interpreting 110.2 (C) (1) is, first off we no longer hand the apprentice a 4x4 for contact release. Second, this should be a topic covered with qualified personnel and should be included in the JHA whenever someone is going to be in Restricted Approach Boundary. That there is no real "approved" method of contact release, but it should be addressed on a case by case basis with the goal of the procedure laid out to ensure, as you said Paul, that no one else becomes a victim. That if the topic of Contact Release is discussed at least once a year during a regular safety meeting that should meet the requirement of 110.2(C)(1) because you have informed all of your qualified people of how to plan accordingly.


Yes, one approach that is in line with the spirit and letter of 70E is to make it clear that doing nothing is acceptable. If you take this approach then if something ever does happen though chances are that this policy will be ignored. So rather than compounding the problem it is probably best to first explain this position and then follow it up with suggestions if someone insists on doing it anyway to give them as much guidance as possible.

There is a little more you can do than that. Let's consider the less difficult one: CPR training which is also required by 70E. CPR training should not theoretically be necessary if everything always goes as planned and everyone follows the rules exactly like they should on every job. But regardless of the reason, things can and do go wrong. In regards to CPR, the best approach from a mental state of mind is to recognize that the victim is in all likelihood already dead. When we do CPR, we are trying to revive them. There is a chance that no matter what we do, they do not revive. So we train for CPR but unless we are trained as full fledged EMT's (not required by 70E) then using CPR to try to revive someone is a voluntary choice.

Contact release is no different. Again somehow in spite of all the precautions a victim got into a situation where they are being shocked but it is still ongoing unlike the CPR case. In this situation again 70E does not require technical rescue training so qualified personnel are not qualified to perform technical rescue operations. The victim is energized and thus a rescue using any means other than killing power would be energized work. If everything went according to the standard we would not be in this situation then contact release would not be necessary. As with CPR the safest approach is to do nothing but that's not to say that someone can't volunteer to attempt a rescue. There are rescue hooks but they need to be available and in all likelihood this will not be the case and even if they are, they must be cleaned and tested just as with hot sticks because otherwise the rescue hook is no better than any other tool.

This means that in all likelihood the tools at our disposal are going to be makeshift. The rest of the discussion should center around what would make a good tool and what would make a poor one. Tools that are designed and tested such as hot sticks are the best choices. A pair of rubber gloves might not be a good choice because it places the volunteer so close to the victim but using rubber gloves to manipulate a questionable makeshift tool such as a 4x4 might be a good approach. Similar remarks can be made about common tools such as rope, lengths of metal conduit, and various rubber goods.


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 Post subject: Re: Clarification on 110.2(C)(1) and 110.3(C)
PostPosted: Mon Jun 27, 2016 10:30 am 
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Thanks Paul, you've given me a lot to look at and work with.


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 Post subject: Re: Clarification on 110.2(C)(1) and 110.3(C)
PostPosted: Thu Jul 28, 2016 4:07 pm 
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As always thanks to all of you for your insights, they really help. To play a bit of devils advocate here if releasing a person who is being shocked would be considered energized work, then couldn't it be justified under exception #1 for energized work "a greater hazard to others". My world is 600V or less and that is the context for my question. If my premise is sound that release could be justified energized electrical work then my next dilemma becomes with what PPE or tools. As mentioned previously the insulated hook would be ideal but what are the odds one would be handy. I would guess most qualified electrical workers would have their insulated gloves nearby but it could take 10s of seconds or even minutes to get and don them. My background is that of Journeyman Electrician and I was taught (40 years ago) to push the victim free with a piece of 2x4, much lighter then a 4x4. My hesitance nowadays (from a liability standpoint) is that the 2x4 would not be "tested and approved" for that task. I am glad that this topic has been brought up since I have always wrestled with what to tell young electrical workers to do in a release situation. I see two scenarios, the first planned energized work where another qualified electrical worker is asked to stand watch. The watch person could stand by a disconnecting means in site of the work or if that isn't feasible could have on their insulated gloves and have an insulated rescue hook in hand. This scenario doesn't trouble me, the one that does is where a worker hears the hollering of someone hung up and is faced with the decision of what to do. No insulated hook, no insulated gloves and 600V or less, what to do, the 2X4?
Thanks in advance for any thoughts on what to advise electrical trainees.


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 Post subject: Re: Clarification on 110.2(C)(1) and 110.3(C)
PostPosted: Fri Jul 29, 2016 4:34 am 
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graino wrote:
As always thanks to all of you for your insights, they really help. To play a bit of devils advocate here if releasing a person who is being shocked would be considered energized work, then couldn't it be justified under exception #1 for energized work "a greater hazard to others". My world is 600V or less and that is the context for my question.


Shutting the power off is not energized work as per the definitions in 70E. It's just operating equipment.

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If my premise is sound that release could be justified energized electrical work then my next dilemma becomes with what PPE or tools.


70E also requires an energized work permit with signoffs on the justification, a planning meeting, etc. You're going to do all of that too, right? 70E does not specify when and where you have to do CPR either, only that qualified workers have to be trained. The reason for the training is that if someone is shocked and goes down, they need blood flow within a few minutes. In the 10+ minutes it takes to do everything in Article 130, they're already dead or even more severely injured. Either way, emergency work is outside the scope of 70E.

If we go down this path, this is what can happen. We have two operators, both of whom have a good view of the situation but are not in harm's way themselves as a massive amount of anhydrous ammonia is dumping out. Both are standing right next to a button that does an emergency closure of all the valves and can stop the leak immediately. Both operators ensue into a heated argument over plant radio on who's responsibility it is and whether or not they have permission to hit the button. The cloud of ammonia then passes through the plant and sends about a dozen other workers nearby to the hospital. This exact scenario occurred in a chemical plant in a local incident a few years ago. Needless to say training had to be revised to focus on the fact that when a person could be injured, everyone has permission to stop it from happening even if it means shutting down production or damaging equipment in the process.

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As mentioned previously the insulated hook would be ideal but what are the odds one would be handy. I would guess most qualified electrical workers would have their insulated gloves nearby but it could take 10s of seconds or even minutes to get and don them. My background is that of Journeyman Electrician and I was taught (40 years ago) to push the victim free with a piece of 2x4, much lighter then a 4x4. My hesitance nowadays (from a liability standpoint) is that the 2x4 would not be "tested and approved" for that task. I am glad that this topic has been brought up since I have always wrestled with what to tell young electrical workers to do in a release situation. I see two scenarios, the first planned energized work where another qualified electrical worker is asked to stand watch. The watch person could stand by a disconnecting means in site of the work or if that isn't feasible could have on their insulated gloves and have an insulated rescue hook in hand. This scenario doesn't trouble me, the one that does is where a worker hears the hollering of someone hung up and is faced with the decision of what to do. No insulated hook, no insulated gloves and 600V or less, what to do, the 2X4?
Thanks in advance for any thoughts on what to advise electrical trainees.


Let's break this down and make it a little more clear. First off recognize that if nobody does anything, the victim is most certainly dead. Second recognize that there cannot be and should not be a requirement to rescue them unless your personnel are EMT's or firefighters trained in technical rescue where as professionals they are responsible for doing a rescue. Keep in mind also that this throws you into a totally different category, well beyond 70E. Otherwise they fall under the good samaritan category and are going to do it on a voluntary basis. This is no different than doing CPR. If you do nothing, you are well within your training and rights to do so. If you voluntarily help out a fellow human being you might be able to revive them from certain death but in many cases no matter how hard you try, they will die anyways.

Second, even if you have a rescue hook, are you going to send it out periodically to get it cleaned and tested? Are you going to keep a second one on hand so that you can rotate it out while the other one is off site? Just saying....

Again, you can't stress enough the value of just shutting off power.

The idea here is not to give out an exact list because again...it's all voluntary and it's all make shift. The goal would be to have a good discussion about choosing appropriate make shift tools. For a lot of very good reasons it is probably best not to even have powerpoint slides or any other kind of documentation beyond spelling out exactly what is in 70E in that the only official method of release is to remove power.

Part of the issue is that if you state to use the rescue hooks, or use 4x4's, or any other specific item, then imagine what happens next. The worker assesses the situation, jumps in a vehicle to drive back to the shop to get a tool, then drives back to the scene, hollering on the plant radio the whole way. That is probably not what needs to happen, if anything. Any tools are going to be what is on hand, so training should focus around selection based on what is around them, not specific items.

When something or someone is removed from an energized circuit, they don't just fall off limply either. There is a magnetic force that propels objects apart with AC and with DC muscles tend to violently retract when they are released from voltage. It's not just a matter of the 12 inches of separation recommended by the shock tables...you've got to think about how much flopping around is going to go on. That should give you some idea of how long something needs to be and why gloves might not be a good idea. Look up the testing videos from Chance on different ground cluster tests to get some idea of how much cables whip around.

Second, consider the insulative value of whatever object you choose to use. There are some that are obviously terrible candidates like a stick of steel conduit. Then there are some that are obvious good candidates like a hot stick or a rescue hook. Then there are a whole host of questionable materials. Rope and wood are common examples. A piece of kiln dried lumber might be a good option for instance but not the cribbing laying in the shop that has been soaked in oil and water for most of it's life. Rubber gloves by themselves might not be a good choice (the length issue) but in combination with something else might be a good option. Similarly some rope is a good insulator and some isn't. When I did a lot of testing on a moisture sensor (basically a continuous duty "megger") I was quite surprised by how many plastics and adhesives were actually not as insulative as I would have thought they were.

If I am ever in this situation I'm going to go into a 3 second analysis. I'm going to assess the situation...first looking around the victim and determining what areas are safe and what are unsafe for ME. Second is thinking about where the disconnect is because that's my best bet even if it takes a 60 second sprint to get to it. Third I'm going to scan the area looking for possible makeshift materials. Calling them tools is a bit of a stretch. After that, I'm going to take immediate action and I don't really care about any energized work rules or what the proper chain of command is.

Remember also according to the CCPS (Center for Chemical Processing Safety) handbooks, during normal every day activities depending on what the task is, people make a mistake about 10% of the time on average. During emergency situations when they feel that they are under pressure and don't have adequate time to think the issue through clearly, the error rate jumps to about 40%. And that's on top of the fact that the situation would not exist if 70E was followed in the first place.


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