Arc Protection!? A Joke?

[Philadelphia Frank]

I started working at a factory a few weeks ago. My new boss warned me
that they had a strict "Arc Protection" procedure in place and it
would I soon be enforced. Apparently the existing electricians laughed
it off. Being the new guy, I suspect I'm about to be the "example",
the guy punished for failing to comply.

The rule is that whenever an electrician opens a cabinet that has the
potential of having a voltage greater than 50 volts present (that's
right 50 - fifty) he must where a hard hat with a flash guard, rubber
gloves, a cotton shirt (as well as cotton undergarments - so much for
my sexy Speedo's) and erect a barrier around the panel to protect
onlookers. The onlookers would no doubt be curious to see what was
going on with the guy dressed up like a freak.

Has anyone had to deal with this situation before? They can't be
serious!. I told the boss it would take 15 minutes to do that for
every job I went on, and I probably open a cabinet 20 times a day. He
said it didn't matter. Fifteen minutes times 20 events certainly ought
to matter! Is anybody anywhere doing this?

Somebody help me.

Frank the frazzled (but not fried) electrician.

 

[daestrom]

I started working at a factory a few weeks ago. My new boss warned me
that they had a strict "Arc Protection" procedure in place and it
would I soon be enforced. Apparently the existing electricians laughed
it off. Being the new guy, I suspect I'm about to be the "example",
the guy punished for failing to comply.

The rule is that whenever an electrician opens a cabinet that has the
potential of having a voltage greater than 50 volts present (that's
right 50 - fifty) he must where a hard hat with a flash guard, rubber
gloves, a cotton shirt (as well as cotton undergarments - so much for
my sexy Speedo's) and erect a barrier around the panel to protect
onlookers. The onlookers would no doubt be curious to see what was
going on with the guy dressed up like a freak.

Has anyone had to deal with this situation before? They can't be
serious!. I told the boss it would take 15 minutes to do that for
every job I went on, and I probably open a cabinet 20 times a day. He
said it didn't matter. Fifteen minutes times 20 events certainly ought
to matter! Is anybody anywhere doing this?

Somebody help me.

Well, there is some new rules about arc-flash protection. But it sounds
like whoever wrote your procedures has gotten it fouled up.

Yes, the number is 50 volts. But if you open a cabinet with something like
120VAC, you don't necessarily need faceshield. There are two distances you
have to be aware of. One for a certain level of barrier and training,
another for a certain level of protective equipment. For example, in our
procedures 120VAC panel you have to rope-off the area at least three feet
from any exposed conductors. This can be as little as a temporary stantion
with caution tape right around the cabinet. The 'distance' for 120VAC for
protective equipment is 'in contact' (means you can't touch live 120VAC
without protective equipment).

For 600VAC MCC and such, the distances are higher. But there are some
exceptions for some activities such as just taking voltage measurements
(perhaps to troubleshoot a problem).

Another part of the requirements is the current capacity. The magnitude of
the 'arc' that may be drawn if a fault should occur. In a switchgear or
MCC, the arc can be large and the PPE requirements are higher than for
1000VDC but tiny fault current (such as in a radiation detector circuit
where the current is in nanoamps).

We've got some 'pretty' pictures of a couple of guys that were burned by the
fire-ball coming from a 600VAC MCC. The flash burns on the guy's face are
enough to make you think twice. Yeah, it was *only* 600VAC.

Lineman working with 'high voltage' have been careful about this stuff for
years, and knew the hazards of arc-flashes. But the 'low voltage' (600V and
below) folks have been hurt often enough that the new rules came out.

BTW, it isn't just any old 'faceshield' either. It must be one with a
specific 'energy absorption' rating listed right on the 'plastic' (usually
something in cal/cm^2). About the only thing worse than a bad arc-flash
burn is one that is compounded by melted plastic from a cheap 'wally world
special' faceshield that melts to your face.

But these requirements apply to *energized* work only. Once the
cabinet/switchgear is *tested* dead, you can take off the PPE.

daestrom

 

[daestrom]

While I was working as an electrician foreman at the Valdez Terminal
for a contractor doing work for the Alyeska Pipeline Service Company in
2001 we had to remove and replace a 100 ampere bolt in breaker in a hot
800 ampere 480 volt panelboard on one of the loading berths. I
attempted to enforce safe work practices by requiring that the
electricians doing the work use proper protective gear including rubber
gloves, face shield, rubber sleeves, fire proof clothing, etc. You
would think I was the first person to ever do this. It required
meetings with the Alyeska safety officer, the contractor safety officer
and superintendent. There were no certified rubber gloves on the site.
Also Alyeska's safety officer told me they had not performed fault
calculations and did not know the available fault current in the panel.
In the end I think a couple of brave Alyeska's direct hire
electricians slipped in and did the work without letting anyone know
who did the work. They made me look like a jerk for trying. So much
for safe work practices at Alyeska without employer support.

Sad, but certainly not the only case. You might point out to them how much
a wrongful death suit costs, and the extent of OSHA's authority in the
matter. Sometimes a letter from OSHA to the corporate offices get's more
attention than the safety supervisor in the field.

daestrom

 

[Philadelphia Frank]

Thanks for the reply.

Like a lot of electricians, I'll go into an energized cabinet
many,many times a day. Things like resetting an overload, checking
fuses, looking at the I/O indicator LEDs, check voltages at specific
points, mainly things that only take a few seconds to accomplish. It
aggravates me to have to "suit up" for no real practical reason.

I suspect, and this is what really gets me angry, that the new rules
are simply legal maneuvering to limit a company's liability if you do
get hurt. If that's the case let it be out in the open. If you don't
dress up, your widow is going to loose money. I would rather hear that
than pretending that the new rules are going to make me safer.

How about crash helmets for the fork truck drivers? Better yet,
plastic bendable forks. I'm much more at risk of getting forked than I
am at getting fried.

And another thing...I'll bet if we really do follow the rules my
company has laid out, at a cost of 15 minutes extra for every service
call, this whole policy might be rethought.
Now I'm starting to rave. Thank you for your help.

Frank

 

[Bud--]

I started working at a factory a few weeks ago. My new boss warned me
that they had a strict "Arc Protection" procedure in place and it
would I soon be enforced. Apparently the existing electricians laughed
it off. Being the new guy, I suspect I'm about to be the "example",
the guy punished for failing to comply.

The rule is that whenever an electrician opens a cabinet that has the
potential of having a voltage greater than 50 volts present (that's
right 50 - fifty) he must where a hard hat with a flash guard, rubber
gloves, a cotton shirt (as well as cotton undergarments - so much for
my sexy Speedo's) and erect a barrier around the panel to protect
onlookers. The onlookers would no doubt be curious to see what was
going on with the guy dressed up like a freak.

Has anyone had to deal with this situation before? They can't be
serious!. I told the boss it would take 15 minutes to do that for
every job I went on, and I probably open a cabinet 20 times a day. He
said it didn't matter. Fifteen minutes times 20 events certainly ought
to matter! Is anybody anywhere doing this?

Somebody help me.

Frank the frazzled (but not fried) electrician.

A continuing education class said OSHA now requires a plan for worker
protection from electrical hazards, including shock and arc flash. My
understanding is that NFPA 70E, mentioned in other threads, is a defacto
standard. Not having -and- following a plan could incurr the wrath of
OSHA, especially if there are injuries. The wrath can include big time
money. Your rules sound like a one-solution fix which may be an over or
under reaction. As others have said, the protection that is appropriate
depends on what you are working on

The plant (and perhaps you) should have a copy of NFPA 70E and read it.
NFPA 70E guidelines for protection from live equipment go from
"untreated natural fiber" clothes (that don't melt) to an arc flash suit
with hard hat and tinted visor - don't know how anyone can work in one
of those. The hazard from arc flash is not just direct heat radiation.
Other hazards include concussive force from rapidly expanding hot air
that could kill you, condensing copper vapor on your skin, shrapnel,
lung damage from very hot air, eye and ear damage. Watching some arc
flash videos I gained a real appreciation for current limiting fuses.


One of the smartest electricians I knew was seriously injured
(hospitalized and plastic surgery for scarring) from arc flash just
amp-clamping a wire in a 480V motor control center module. (The guess is
that there was a loose screw that caused a fault.)

bud--

 

[Andrew Gabriel]

Thanks for the reply.

Like a lot of electricians, I'll go into an energized cabinet
many,many times a day. Things like resetting an overload, checking
fuses, looking at the I/O indicator LEDs, check voltages at specific
points, mainly things that only take a few seconds to accomplish. It

If these things need doing many times a day, the LEDs and suitable
voltage meters should be fitted remotely from energized cabinets
with exposed live parts, or such that they can be viewed without
opening access to live parts, so they can be checked safely.
Access to live parts should not come as a side effect of performing
some other unrelated task, most particularly a common task.
At least, this is the view which would be taken in the UK.

aggravates me to have to "suit up" for no real practical reason.

Sounds like it's due to bad system design.

 

[[email protected]]

| In article <[email protected]>,
|> Thanks for the reply.
|>
|> Like a lot of electricians, I'll go into an energized cabinet
|> many,many times a day. Things like resetting an overload, checking
|> fuses, looking at the I/O indicator LEDs, check voltages at specific
|> points, mainly things that only take a few seconds to accomplish. It
|
| If these things need doing many times a day, the LEDs and suitable
| voltage meters should be fitted remotely from energized cabinets
| with exposed live parts, or such that they can be viewed without
| opening access to live parts, so they can be checked safely.
| Access to live parts should not come as a side effect of performing
| some other unrelated task, most particularly a common task.
| At least, this is the view which would be taken in the UK.

You think a cheapskate company like the one the OP works for would
shell out for that?

It seems clear to me that they went overboard on this, fully suspecting
that electricians would not actually follow the procedure. This was
done strictly for legal liability issues so they don;t have to pay out.
It might be the sign of having acquired a cheaper insurance policy.
I suspect they will not actually be enforcing this. I would like to
see rules or court decisions that consider lack of enforcement as being
equivalent to lack of policy. In other words, if they do not actively
enforce the procedure they have in place for all people for all work,
then they have to pay out in the case of an accident just as if they
had no policy in place at all.

To the OP: I suggest a small camera with a date recorder. It's not so
much to get others in trouble, but rather, to have on record the way the
procedures actually are followed and enforced. Then it's up to you to
decide whether the evidence warrants being presented before an accident,
or in court after an accident.

 

[[email protected]]

On Wed, 18 Oct 2006 11:44:36 GMT [email protected] wrote:

| Another matter altogether is the flash protection boundary, which has to do
| with the distance away from the energized components that fire-resistant
| PPE is required. Depending on the available arc-flash energy, this can be
| a matter of inches (typical 120V control panel) or may be 10s of feet (480V
| service-entrance equipment). Unqualified personnel are likewise prohibited
| from entering the flash protection boundary.

Available fault current is a big factor here, too. Usually, large
currents are present with large voltages just because when a big
load needs more power, it's generally a combination of more current
and more voltage.


| Exactly. The rules aren't there to make life difficult. They're there to
| try and keep people out of the hospital. 10-15 extra minutes suiting up to
| go into an MCC is a whole lot less time-consuming than three months in a
| burn unit. And yes, lots of people are doing this.

.... the hospital or the morgue.


| I'm not sure what the major issue is. With the possible exception of the
| "flash guard" (whatever that is) the original PPE description sounds about
| right, and is really minimal as far as fire-resistant PPE is concerned. At
| many locations (480V service entrance gear, medium-voltage equipment, MCCs,
| large distribution panels) you really should be wearing more than this.

How much more dangerous is a 480 volt service than a 240 volt service
when both come from the same kVA transformer? Suppose your home is a
significant distance from the roadway and 240 volts would be too much
of a voltage drop, and running MV would be too expensive (or like me,
maybe you just don't want any MV on your land at all). Suppose the
service originates in a 50 kVA pole transformer at the road and you
have a 50 kVA dry transformer to step the 480 down to 120/240. Just
how much more dangerous is that over the service originating at 120/240
in a 50 kVA pole transformer at the road and the drop running only 1/4
the distance to a closer house? Assume the same impedance percentage
for the transformer. Which has the higher fault current?

Certainly 480 volts is not less safe. But there are many factors and
they change with a change in voltage and current.


| Your employer is on the right track, but may need to provide additional
| safety training so that you and your fellow employees truly are aware of
| and appreciate the potential hazards you face.

Some videos and photos of the electricians that "barely made it" might be
of help.

 

[Matthew Beasley]

Some videos and photos of the electricians that "barely made it" might be
of help.

An electrician I know made me a believer. He was the "safety watch" person
when live work was going on. The two guys doing the actual work were
wearing flash protection. They were pulling wires into a MCC pan, and with
"luck" manage to stick a wire through the guarding and short the bus. The
two wearing all the gear and right by the MCC were not hurt. They guy I
know was 10' away and suffered from both radiant burns and injuries from
flying molten metal. Not bad enough to make him stay in the hospital, but
painful.