Arc Flash Suits for Disconnects?

[cowboyjwc]

1910.332 - In fact for electrical related violations this is the most common article cited and fined
https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=standards&p_id=9909

This is about to be revised to mirror the NFPA 70E training requirements which are much more specific

So as to the original question, should PPE be worn when operating a disconnect switch? And is it possible for a disconnect switch to produce enough energy for a serious arc flash? I say yes.

 

[petersonra]

So as to the original question, should PPE be worn when operating a disconnect switch? And is it possible for a disconnect switch to produce enough energy for a serious arc flash? I say yes.

The requirement to wear a suit is based on the amount of energy that the person might be exposed to if an arc flash incident occurs.

So, the answer to your question is complicated by the fact that many (possibly most) disconnect switches just do not have enough energy available to require the suit.

Assuming that merely operating a disconnect switch exposes one to whatever energy level might be available at the switch seems like a dubious assumption to me. Energized disconnect switches have routinely been operated without incident for many, many years. That does not mean it is impossible for an incident to occur.

I think you can do one of two things. In the first case you can look closer at each individual circumstance and make a determination as to the hazard level for each one and require whatever level of PPE is appropriate.

The other answer is to just make a blanket rule that a suit is required to operate any disconnect switch. However, this is not necessarily safe since it is possible more energy is available than a suit will protect one from in the event of an incident. Which brings you back to having to look at each case on its own merits.

I think a good argument can be made that basic PPE (glasses, boots, etc.) is always required when working on electrical equipment. How far to take it is something that I think has to be determined on a case by case basis.

 

[jim dungar]

...when working on electrical equipment. ...

NFPA70E says Arc Flash PPE is need when 'interacting in a manner that will cause an arc flash'. So it tacitly acknowledges there are interactions that do not cause arc flash incidents.

 

[kwired]

If taken too literally people would need to suit up when operating a wall switch for general lighting. Close that switch into a fault and there is going to be an arc, but how much of one is not necessarily the same for every switch out there. Plus you are usually at a point in the circuit where the incident energy level is usually not going to be seriously high, but still could potentially cause some injury or at very least scare the poop out of the user.

 

[iwire]

If taken too literally people would need to suit up when operating a wall switch for general lighting. Close that switch into a fault and there is going to be an arc, but how much of one is not necessarily the same for every switch out there. Plus you are usually at a point in the circuit where the incident energy level is usually not going to be seriously high, but still could potentially cause some injury or at very least scare the poop out of the user.

You are missing an important factor that makes all the difference. The user.

Disconnect switches and other equipment are used by workers that must follow the directions of the suit and tie folks.

The suit and tie folks are not going to make rules that inconvenience themselves.

 

[just the cowboy]

Where does LOTO fall

Where does LOTO fall

If from what is being said PPE is required for throwing a disconnect, how does this apply for LOTO by operators? LOTO says a blade type disconnect should be used. Coming from a company that installed 100's of disconnects so operators could safely "lock out equipment when clearing a jam" does this mean that ALL OPERATORS have to suit up. We did allot of control work so loads were shut off first, but that don't say you can't have a fault.

Just another monkey wrench to add. :happyyes:

 

[iwire]

If from what is being said PPE is required for throwing a disconnect, how does this apply for LOTO by operators? LOTO says a blade type disconnect should be used. Coming from a company that installed 100's of disconnects so operators could safely "lock out equipment when clearing a jam"

How where the operators checking to see if the equipment was dead after putting the disconnect in the off position?


BTW, I do not think OSHA requires a blade type switch.

 

[mayanees]

70E 2015 changes

70E 2015 changes

An advanced issue of the changes being adopted for 70E 2015 shows an addition to section 130.2(A) Energized work. Currently it's: 130.2(A)1 when greater hazard exists if not addressed, (A)2 Infeasibility (e.g. troubleshooting), (A) 3Less than 50 Volts, and now (A)4 Normal Operation, stating that normal operation of electric equipment shall be permitted where 5 conditions are met: 1-installed properly, 2-maintained, 3-doors closed and secured, 4-covers in place, 5-no evidence of impending failure.
I think this is acknowledgement that the risk is low. What I can't tell from what was published (EC magazine, Change is on the way! 2015 NFPA 70E) is the PPE requirement. I think this means that disconnect switches can be operated without PPE.
This stance is taken by Square D Data Bulletin 0100DB0804R11/09, PPE Recommendations, which lists four types of Square D gear: Power Zone II, 4, QED-6, QED-2, that shows "normal" switching is PPE 0, with similar stipulations, including commissioning and under load for some time.
This would make much more sense for the industry as a whole, to be able to operate a disconnect switch without PPE.
But then what if there are 100 calories available at the switch...??.. Perhaps the facility's Electrical Safety Program excludes those conditions.
Opinions welcomed!

 

[iwire]

I think this is acknowledgement that the risk is low.

The problem I see is if a company allows the task to be done without PPE and something does happen ... as remote as it may be, they will hung for non-compliance.

 

[zog]

So as to the original question, should PPE be worn when operating a disconnect switch? And is it possible for a disconnect switch to produce enough energy for a serious arc flash? I say yes.

"Disconnect switch" is pretty vauge and the device itself has little to do with the seriousness of the arc flash, all depends on the fault current at that point and the clearing time of the OCPD upstream of it. When I hear disconnect switch I think of a 15kV switch feeding a transformer, or maybe a 480V switch feeding a machine in an industrial plant.

 

[zog]

An advanced issue of the changes being adopted for 70E 2015 shows an addition to section 130.2(A) Energized work. Currently it's: 130.2(A)1 when greater hazard exists if not addressed, (A)2 Infeasibility (e.g. troubleshooting), (A) 3Less than 50 Volts, and now (A)4 Normal Operation, stating that normal operation of electric equipment shall be permitted where 5 conditions are met: 1-installed properly, 2-maintained, 3-doors closed and secured, 4-covers in place, 5-no evidence of impending failure.

The trick is now going to be who determines those conditions are met? I am in plants all the time where the equipment has never been tested, breakers never refirbished per OEM IB's, not much more than annual cleaning and the EE or Maintenence manager thinks his equipment is "Properly maintained". This equipment condition assesment IMO will be the new frontier in the world of 70E compliance.

What I can't tell from what was published (EC magazine, Change is on the way! 2015 NFPA 70E) is the PPE requirement. I think this means that disconnect switches can be operated without PPE.

There will be a seperate table for PPE requirements for equipment that meets the 5 conditions you stated above. PPE will still be required but mostly HRC 0 or at least reduced levels from "not properly maintained" equipment.

 

[kwired]

"Disconnect switch" is pretty vauge and the device itself has little to do with the seriousness of the arc flash, all depends on the fault current at that point and the clearing time of the OCPD upstream of it. When I hear disconnect switch I think of a 15kV switch feeding a transformer, or maybe a 480V switch feeding a machine in an industrial plant.

Many people may envision a particular type of switch, but in reality a simple AC/DC snap switch can be a "disconnecting means" required by NEC. Not too often are those located at a point in a circuit where the available energy level is high enough to be much problem, which gets us back to the office secretary needing to suit up to turn on the lights in the office if we want to be real strict with the application here. Even possibly more dangerous is plugging any device into a typical 5-15 or 5-20 receptacle. You are more directly exposed to the potential arc in that instance.

 

[zog]

Many people may envision a particular type of switch, but in reality a simple AC/DC snap switch can be a "disconnecting means" required by NEC. Not too often are those located at a point in a circuit where the available energy level is high enough to be much problem, which gets us back to the office secretary needing to suit up to turn on the lights in the office if we want to be real strict with the application here. Even possibly more dangerous is plugging any device into a typical 5-15 or 5-20 receptacle. You are more directly exposed to the potential arc in that instance.

Exactly my point, depends on the system. But once you get to the point when an arc will not be self sustaining there is very little, if any, arc flash hazard, just a shock hazard. It drives me nuts when people say things like "Next thing you know we will need PPE to operate a light switch", they clearly do not understand anything about arc flashes or the intent of the 70E.

 

[iwire]

It drives me nuts when people say things like "Next thing you know we will need PPE to operate a light switch", they clearly do not understand anything about arc flashes or the intent of the 70E.

:lol:

They say that because of being subjected to company policies that disregard calculations and put out blanket requirements that must be met.

 

[zog]

:lol:

They say that because of being subjected to company policies that disregard calculations and put out blanket requirements that must be met.

That's just lazy policy by the safety manager who has no idea what he/she is talking about either.

P.S. My last comment was not meant to imply kwired didn't know what he was talking about, in case it apperaed that way.

 

[kwired]

That's just lazy policy by the safety manager who has no idea what he/she is talking about either.

P.S. My last comment was not meant to imply kwired didn't know what he was talking about, in case it apperaed that way.

No offense taken. I know a lot of things, but also venture into territory I am not all that familiar with. I have not studied 70E to much extent, most of what I do know about it is what I have learned from this site. I know less about OSHA, but mostly understand that you need an electrical safety standard, though OSHA doesn't have much to go on other then you must protect employees from the hazards of electrical energy and that adopting something like 70E is usually going to be better then attempting to make your own standard.

 

[iwire]

That's just lazy policy by the safety manager who has no idea what he/she is talking about either.

Yes, for sure. From my personal experience and reading the forums much more common than not.

P.S. My last comment was not meant to imply kwired didn't know what he was talking about, in case it apperaed that way.

I did not take it that way. (There would be a smile here if I did not know you hate them)

 

[cowboyjwc]

Yes, for sure. From my personal experience and reading the forums much more common than not.







I did not take it that way. (There would be a smile here if I did not know you hate them)

Zog hate smiley's? How come?:? Smiley's are good:happyyes:

 

[zog]

Zog hate smiley's? How come?:? Smiley's are good:happyyes:

I don't hate them, I just hate when a post is nothing but a smiley. Why bother?

 

[ggunn]

View attachment 10572

That's a different kind of flash suit.