Arc Flash PPE clothing requirements

[mull982]

I am reviewing an Arc Flash study and looking at NFPA70E trying to determine exactly what clothing is required for each PPE level. Here at our facility we have a 100Cal Arc Flash suit but I am trying to determine what is needed for lower IE levels such as category 2&3

Category 2 and 3 in 70E both require Arc-rated pants long sleve shirts, or coveralls rated for the required Arc levels. If I understand correctly in lieu of these items you can wear a properly rated Arc Flash suit rated for the IE levels of each category.

My question is if there is not an Arc Flash suit avalabile on site for category 2's adn 3's what type of normal cloting is acceptable? For example are jeans which is what most employees wear considered an acceptable Arc-rated long pants for either category? Is long sleve FR shirt that most employees issue to mechanics consided an Arc-Rated shirt for either category? If neither the pants or shirt I described is acceptable then must a suit or coveralls rated for the appropriate level be worn?

What about as far as headgear. It appears that all categorys except cat 0 require an Arc rated face shield. It looks like a face shield is acceptable for categorys 1 and 2 but a hood is required for category's 3&4. Is this correct? With a face shield must you have something else covering your ears and the back of your head?

One other thing I am noticing in the study results is that for some pieces of equipment the Arc Flash boundery is extremely large. In some cases the boundary is larger than the room itself and would put people outside the room who need to stay outside the Arc Flash boundary. I was curious to see how others treated these cases.

 

[billsnuff]

I work in a 100,00 sq ft manuf facility as maint mgr. Had AF Study done.
No live work except volt measurements. All my mechanics and Elecs. wear
cotton under uniforms that I supply. HRC 2 jean and long sleeve shirt. (8 Cal)

Also provide hard hat with face shield 16 cal, 1000volt gloves and covers. New gloves every 6 mo. (new color also)

If higher you would need a balaclava (head sock)

Anything higher that 2, I call outside help. I have the same PPE also.

Our working limit (in house) is HRC 2

 

[skeshesh]

Bill covered the idea rather nicely. I'll just add that if the arc flash study indicates a hazard level above a PPE category then shut-down is required to do the work.

 

[zog]

I am reviewing an Arc Flash study and looking at NFPA70E trying to determine exactly what clothing is required for each PPE level. Here at our facility we have a 100Cal Arc Flash suit but I am trying to determine what is needed for lower IE levels such as category 2&3

Category 2 and 3 in 70E both require Arc-rated pants long sleve shirts, or coveralls rated for the required Arc levels. If I understand correctly in lieu of these items you can wear a properly rated Arc Flash suit rated for the IE levels of each category.

Yes, note 8 in table 130.7(C)(10)

My question is if there is not an Arc Flash suit avalabile on site for category 2's adn 3's what type of normal cloting is acceptable? For example are jeans which is what most employees wear considered an acceptable Arc-rated long pants for either category? Is long sleve FR shirt that most employees issue to mechanics consided an Arc-Rated shirt for either category? If neither the pants or shirt I described is acceptable then must a suit or coveralls rated for the appropriate level be worn? [non melting, FR, and arc rated are all different things. Your clothing needs to be arc rated with an ATPV that is > the Ei.

What about as far as headgear. It appears that all categorys except cat 0 require an Arc rated face shield. It looks like a face shield is acceptable for categorys 1 and 2 but a hood is required for category's 3&4. Is this correct? With a face shield must you have something else covering your ears and the back of your head?

Yes, but you need the hood, or a shield with head sock for 2*

One other thing I am noticing in the study results is that for some pieces of equipment the Arc Flash boundery is extremely large. In some cases the boundary is larger than the room itself and would put people outside the room who need to stay outside the Arc Flash boundary. I was curious to see how others treated these cases.

There are many mitigation options for different senarios (I do seminars on this at conferences), part of your arc flash study should have included mitigation recommendations for anything >HRC 3 from the EE that performed the study.

No one should have to deal with an arc flash boundry like that, mitigation is usually simple to accomplish. The best way to protect your people from a hazard is to remove or at least minimize the hazard.

 

[billsnuff]

In order to determine LOTO, Me and my crew did risk assessments and filled out a LOTO Matrix for each task as to what to lock out and where.

we also identified routine tasks, with appropriate steps to cut down on the number of ESWP we have to fill out.

training was carried out on all routine tasks.

it covered: Equip ID - Task - Boundary - who can LOTO - will boundary be crossed - Safeguard(s) PPE - Verification / Notification

 

[MIEngineer]

When you say you call for outside help if >HRC 2. Does that include voltage testing in a panel that has been determined, through AF study, to be >HRC 2? I am specifically referring to equipment such as MCCs and larger distribution panels. The task is the same as in a 480V panelboard but the hazard category is larger.

We are looking at it as the cost of the PPE and training for our people is cheaper than a service call, when our in-house people are trained for voltage testing.

Thanks,

 

[zog]

We are looking at it as the cost of the PPE and training for our people is cheaper than a service call, when our in-house people are trained for voltage testing.

Thanks,

You planning on calling someone out every time you operate a breaker or switch?

 

[mull982]

non melting, FR, and arc rated are all different things. Your clothing needs to be arc rated with an ATPV that is > the Ei.

So do a typical pair of jeans have an arc rating with an ATPV that is greater than 4 or 8 cal/cm^2?

What about a typical cotton shirt?

Yes, but you need the hood, or a shield with head sock for 2*

So are you saying that for Categories 1 and 2 an appropriately rated faceshield is o.k. with or without the sock, however for category 2* you definitely need to the head sock with the faceshield. And for categories 3&4 you need to have the Arc Flash hood?

There are many mitigation options for different senarios (I do seminars on this at conferences), part of your arc flash study should have included mitigation recommendations for anything >HRC 3 from the EE that performed the study.

No one should have to deal with an arc flash boundry like that, mitigation is usually simple to accomplish. The best way to protect your people from a hazard is to remove or at least minimize the hazard.

Yes there were mitigation recommendations given in the report. Most of the mitigation techniques are in the form of revised breaker setttings (instantaneous settings etc...) The Arc Flash boundary that I listed is after the mitigation recommendations have been implemented.

Are you saying that most Arc Flash reports should strive to get all PPE levels down to Category 3 or less? It looks like in some cases this is just not possible such as the secondary of a transformer with no main secondary breaker?

 

[billsnuff]

When you say you call for outside help if >HRC 2. Does that include voltage testing in a panel that has been determined, through AF study, to be >HRC 2? I am specifically referring to equipment such as MCCs and larger distribution panels. The task is the same as in a 480V panelboard but the hazard category is larger.

Yes, we decided not to work above HRC 2*.

Besides the main switch, I only have one or two LPs and we are working on mitigation for them. We can work in the buckets, but we can't rack them.

 

[zog]

We can work in the buckets, but we can't rack them.

You could use a remote bucket extractor

 

[billsnuff]

Sq D circa '65, no dividers/barriers between sections, > 40 cal.

have to have POCO shut down building......I'll just call for backup......

 

[zog]

So do a typical pair of jeans have an arc rating with an ATPV that is greater than 4 or 8 cal/cm^2?

What about a typical cotton shirt?

Neither are arc rated.

So are you saying that for Categories 1 and 2 an appropriately rated faceshield is o.k. with or without the sock, however for category 2* you definitely need to the head sock with the faceshield. And for categories 3&4 you need to have the Arc Flash hood?

Yes but the shield needs to have the correct arc rating and be a wrap around design (Note 7)

Yes there were mitigation recommendations given in the report. Most of the mitigation techniques are in the form of revised breaker setttings (instantaneous settings etc...) The Arc Flash boundary that I listed is after the mitigation recommendations have been implemented.

You can do better, we can discuss specifics if you like.

Are you saying that most Arc Flash reports should strive to get all PPE levels down to Category 3 or less?

Well not the report but the mitigation recommendation should (I assume that is what you mean). Mitigation is constantly evolving, new ideas and products comming out all the time.

Put it this way, if you had a wasp nest in your garage would you put on a bee keepers suit every morning to go get inyour car or would you have the nest removed?

It looks like in some cases this is just not possible such as the secondary of a transformer with no main secondary breaker?

No main huh? (Paper mill by chance?) That complicates things, but still possible (Stupid design build type "cost savings"). I have an IEEE paper on mitigation with no main breaker I can send you if you like. I am also working on a new solution for this.