Residential electrical procedures and PPE

[hillbilly1]

Don’t forget, if you ever use your gloves without the leathers, you cannot use them again until they are tested.

 

[SSDriver]

I put split bolts on the phase wires with my bare hands or with regular work gloves for the last 25 years for overhead stuff. This is while on a fiberglass ladder or composite roof. I know this is not good, old habits die hard. How I was taught.

I know a lot of electricians who do this. I'm sure a few here still do but won't admit it here.

 

[scottwnuwer]

Incident energy would be determined by one of two methods:
130.5(F) Arc Flash PPE.
One of the following methods shall be used for the selection of arc flash PPE:
(1) The incident energy analysis method in accordance with 130.5(G)
(2) The arc flash PPE category method in accordance with 130.7(C)(15)
Whether or not PPE is required for a specific task is guided by Table 130.5(C) Estimate of the Likelihood of Occurrence of an Arc Flash Incident for ac and dc Systems. From this table you can determine that when removing covers on an energized system in any condition there is a likelihood of occurrence of an arc flash incident, so PPE must be worn.

Understood, but in order to even use the arc flash PPE category method of Table 130.7(C)(15)(a), the qualified person must already know several key pieces of information:

The voltage of the equipment being worked on while energized (obvious)
The maximum available fault current at the equipment being worked on (I have the utility provided chart for specific transformer sizes and their respective secondary fault currents @ 240V)
The maximum fault clearing time of the overcurrent device protecting the equipment being worked on (I will need to contact the utilities to confirm, but I do not believe that any of their secondary protection is going to clear a fault in 2 cycles or less - 0.03seconds)
The needed working distance in order to perform the task

If any one of the above are not known, or the information known does not allow you to fall into a specific parameter, then Table 130.7(C)(15)(a) cannot be used and an incident energy analysis must be performed instead of using the Table. Am I wrong?

I must apologize for my ignorance in safety. As an electrical contractor, I should know about the requirements of OSHA and NFPA70E. Prior to a year ago, arc flash was not a concern of mine, and even now it seems as though it's slightly hyped up more than it needs to be for residential single phase 120/240V (You can tell that I have never had first-hand experience in this area) However, upon possibly hiring employees (other than myself), it's very important to make certain that I have a standard protocol for safety that meets or exceeds OSHA regulations and NFPA70E. If for nobody else right now, than for me. I understand how most people probably feel regarding residential electrical single phase 120/240V. It's not a big deal, wear your gloves at a minimum. If you feel safer to suit up, then do it. I guess I am trying to fully understand what OSHA and NFPA70E expect from a typical residential electrical service call.

 

[mayanees]

Understood, but in order to even use the arc flash PPE category method of Table 130.7(C)(15)(a), the qualified person must already know several key pieces of information:

The voltage of the equipment being worked on while energized (obvious)
The maximum available fault current at the equipment being worked on (I have the utility provided chart for specific transformer sizes and their respective secondary fault currents @ 240V)
The maximum fault clearing time of the overcurrent device protecting the equipment being worked on (I will need to contact the utilities to confirm, but I do not believe that any of their secondary protection is going to clear a fault in 2 cycles or less - 0.03seconds)
The needed working distance in order to perform the task

If any one of the above are not known, or the information known does not allow you to fall into a specific parameter, then Table 130.7(C)(15)(a) cannot be used and an incident energy analysis must be performed instead of using the Table. Am I wrong?

I must apologize for my ignorance in safety. As an electrical contractor, I should know about the requirements of OSHA and NFPA70E. Prior to a year ago, arc flash was not a concern of mine, and even now it seems as though it's slightly hyped up more than it needs to be for residential single phase 120/240V (You can tell that I have never had first-hand experience in this area) However, upon possibly hiring employees (other than myself), it's very important to make certain that I have a standard protocol for safety that meets or exceeds OSHA regulations and NFPA70E. If for nobody else right now, than for me. I understand how most people probably feel regarding residential electrical single phase 120/240V. It's not a big deal, wear your gloves at a minimum. If you feel safer to suit up, then do it. I guess I am trying to fully understand what OSHA and NFPA70E expect from a typical residential electrical service call.

You are correct.
It doesn't apply to lots of conditions.
70E advises using IEEE 1584 for calculating the incident energy and 1584 states that an arc flash is not likely to occur unless there are 2000 amps of bolted fault current. That implies a cutoff of about a 30 kVA transformer for anything over 1.2 calories of incident energy. This eliminates arc flash from many residential services because they're served by transformers smaller than 30 kVA.
Arc flash occurrences are relatively rare compared to shock incidents. I think there are around 125 electrical deaths per year, of which only 3 are arc flash related.
I think the industry has overreacted to arc flash, because you can't work on a piece of equipment when it's energized unless it's more dangerous to turn it off. There are many cases where the risk is minimal. Take for example a Power Distribution Unit in a Data Center where there are multiple 225-amp, 3-pole breakers for Remote Power Panels. I think cables can be safely terminated on one of the breakers without turning the PDU off; however, that's not allowed. Even the installation of CTs for power monitoring must have an Energized Electrical Work Permit for their temporary installation because the cable is being touched.
There are some things that can be done though on an energized system based on 70E table 130.5(C).
Good luck.

 

[infinity]

Where I work we don't follow 70E and no one cares if you're working on something energized, in fact it's expected of you to do so.

The safety guys only care that you're wearing a hard hat and do not care if you're working in live panels or on energized circuits.

I never really got these restrictions, if someone is properly trained why can't they work on something energized, lineman do this every day. In the past 35 years I've gone through thousands of hours of schooling and hundreds of hours of safety training so in the real world I'm perfectly capable of working on an energized panel.

 

[electrofelon]

Where I work we don't follow 70E and no one cares if you're working on something energized, in fact it's expected of you to do so.

The safety guys only care that you're wearing a hard hat and do not care if you're working in live panels or on energized circuits.

I never really got these restrictions, if someone is properly trained why can't they work on something energized, lineman do this every day. In the past 35 years I've gone through thousands of hours of schooling and hundreds of hours of safety training so in the real world I'm perfectly capable of working on an energized panel.

A-men to that. I know sometimes on this forum people will scold other people for working hot. I'm a big boy and know what I'm doing (and I'm self-employed so OSHA doesn't apply to me). There are a lot of situations in life I must pass through that I feel are a lot more dangerous than working on a hot panel or service drop.

 

[kwired]

And people wonder why there is DIY work since OSHA doesnt apply to DIY. I dont pull the meter to work in my own panel. It is one of the newer ones now where the line lugs are covered with boots so it is safer than in the past.

I did have the meter pulled when I changed the main panel. That process sucked as you have to call and it was a 30 minute wait to talk to someone. You call that same number again and wait when you are ready for reconnect. So it was same day service but an hour wasted on hold. And I think it was about $300 for that. Had to get the inspector there too before reconnect but he was actually prompt and easy. They are tasked online.

The newly mandated fireman disconnect will make those houses easier to work on if it is just a disconnect and not a whole 3R panel placed outside.

The "O" in OSHA stands for occupational. Unless maybe you put yourself on a payroll for the DIY stuff you do, it isn't really an occupational situation is it?

 

[suemarkp]

That was my point. The that occupational regulatory over reach will drive up prices and incur delays, causing people to DIY things.

 

[kwired]

That was my point. The that occupational regulatory over reach will drive up prices and incur delays, causing people to DIY things.

I DIY a lot of things like plumbing, construction, mechanical work on just about any sort of thing, but even though the price is high I still don't do much for medical treatment other than some first aid types of things.

 

[Hv&Lv]

A-men to that. I know sometimes on this forum people will scold other people for working hot. I'm a big boy and know what I'm doing (and I'm self-employed so OSHA doesn't apply to me). There are a lot of situations in life I must pass through that I feel are a lot more dangerous than working on a hot panel or service drop.

A lot of linemen (and some in all occupations)without all their parts they were born with say that…

But, yes. I agree totally there are situations where the process to make something safe is more dangerous than the actual act or task you’re trying to accomplish.

 

[kwired]

A lot of linemen (and some in all occupations)without all their parts they were born with say that…

But, yes. I agree totally there are situations where the process to make something safe is more dangerous than the actual act or task you’re trying to accomplish.

Not as many one armed farmers around here anymore as there was say 30-40 years ago. Most of them probably lost it in a tractor PTO shaft accident of some sort.

 

[electrofelon]

A lot of linemen (and some in all occupations)without all their parts they were born with say that…

But, yes. I agree totally there are situations where the process to make something safe is more dangerous than the actual act or task you’re trying to accomplish.

And it just seems ridiculous to have a blanket "no hot work" requirement. Why should working on a small resi panel be treated the same as working on a 4000A 480 switchgear? Granted there is stuff in the middle where it isn't that easy or clear to determine the risk.

 

[kwired]

And it just seems ridiculous to have a blanket "no hot work" requirement. Why should working on a small resi panel be treated the same as working on a 4000A 480 switchgear? Granted there is stuff in the middle where it isn't that easy or clear to determine the risk.

Shock hazards don't really change other than in a dwelling you typically not seeing over 120 volts nominal to ground, but risk of touching something live doesn't really change. Incident energy, can be much higher in non dwellings, but at same time can be higher in a dwelling than some specific situations in a non dwelling - too many variables involved and is all over the place in all sorts of situations.

I've seen or known about faults on branch circuits that also tripped a 200 amp main breaker in dwellings. You don't see that very often but if enough current flows it will happen.

 

[infinity]

And it just seems ridiculous to have a blanket "no hot work" requirement. Why should working on a small resi panel be treated the same as working on a 4000A 480 switchgear? Granted there is stuff in the middle where it isn't that easy or clear to determine the risk.

I agree. The thought of pulling a residential meter to work on the panel is as dumb as the person who came up with that drivel.

 

[kwired]

I agree. The thought of pulling a residential meter to work on the panel is as dumb as the person who came up with that drivel.

Pulling the meter is a task that involves "hot work", and quite frankly is more dangerous task than working in a panel that at least has barriers on the main lugs and the main is turned off. You won't know if that meter socket insulator the jaws are mounted on is broken until it is too late and it shorts to the cover or whatever when pulling the meter.

 

[Hv&Lv]

Pulling the meter is a task that involves "hot work", and quite frankly is more dangerous task than working in a panel that at least has barriers on the main lugs and the main is turned off. You won't know if that meter socket insulator the jaws are mounted on is broken until it is too late and it shorts to the cover or whatever when pulling the meter.

Ding! Ding! Ding!

Our guys absolutely hate to pull some meters that are in old bases for this exact reason.
it’s also the reason they like CSP transformers because they have a relatively low amp breaker in them.

 

[kwired]

Ding! Ding! Ding!

Our guys absolutely hate to pull some meters that are in old bases for this exact reason.
it’s also the reason they like CSP transformers because they have a relatively low amp breaker in them.

They should at least stop making ringless meters or other styles that you don't first need to remove a cover before pulling the meter, then at least there isn't something for the jaw assembly to short to if it separates. JMO.

Will add one the rural POCO's here pretty much always pulls fuses on the primary on most typical irrigation and other three phase farm services. They even have in their construction standards that those primary fuse holders be on opposite side of the pole that the meter socket is on. That way if closing into a fault it can't launch that meter or portions of it at the person using extension stick to install the fuses.

 

[mtnelect]

UPS drivers are instructed not to take left turns, only right turns. Maybe the time has come to stop working things live. A better choice would be to make the customer wait.

 

[kwired]

UPS drivers are instructed not to take left turns, only right turns. Maybe the time has come to stop working things live. A better choice would be to make the customer wait.

If true they don't follow that around here. They come to local town from the west and first three or four businesses that they would make fairly regular stops at are all on north side of road. Left turn to get into each one, left turn when leaving each one to go further into town. Even if they were to circle around and catch them later, a left turn would still need to be made at some point in order to be headed west on that same street.

 

[mtnelect]

If true they don't follow that around here. They come to local town from the west and first three or four businesses that they would make fairly regular stops at are all on north side of road. Left turn to get into each one, left turn when leaving each one to go further into town. Even if they were to circle around and catch them later, a left turn would still need to be made at some point in order to be headed west on that same street.

I forgot to say at intersections only without left turn signal control, sorry.