1. Thinking that it's "only 120 volts" or 208 volts or 480 volts or...
"It's only low voltage." Okay, I'll admit that you can have an open
casket with a low-voltage hit, but you'll still be dead. The only
difference between low and high voltage is how fast it can kill you.
High voltage kills instantly; low voltage may take a little longer.
Dr. A.G. Soto, consulting physician to Ontario Power Generation
presented a paper at the 2007 IEEE Electrical Safety Workshop discussing
low-voltage shock exposures. In that paper, he stated that a 120-volt
shock can kill up to 48 hours later. He also stated that many emergency
room physicians are unfamiliar with electric shock and that an EKG may
not show a problem. The injury to the heart muscle tends to spread over
time and cannot always be identified using EKGs.
2. Working on energized systems or equipment when it can be de-energized.
This is a "man-thing". When I was working in a power plant (back in the
70s), we never de-energized anything, whether it could be or not. My
boss had a great contempt for anyone sissy enough to actually ask to
de-energize before working. He would tell anyone foolish enough to
suggest turning it off, "You're an electrician, work it hot! That's what
you're trained to do!" His other favorite saying was, "If you want to
be here tomorrow, you'll get this done today". Can you feel the love?
De-energizing is the only way to eliminate hazards. Arc flash personal
protective equipment (PPE) just increases your chances of survival; it
doesn't guarantee it. Just be aware that until equipment and systems are
placed in an electrically-safe work condition, proper PPE and
procedures must be used to protect the worker. See Article 120 in NFPA
70E 2009.
3. Not wearing PPE.
This could go into
number 2 above, but people really don't like wearing rubber insulating
gloves or arc flash PPE and equipment. It's hot, uncomfortable,
restricts movement, and slows the entire work process down -- not only
by wearing it, but by selecting the correct PPE and putting it on and
taking it off. It will also save your life. One of the most likely times
people neglect to wear their PPE is during troubleshooting. The
rationale seems to be, "I'm not really working on it; I'm just testing
it." Yet, CDC/NIOSH studies have found that 24% of electrical accidents
are caused by troubleshooting, voltage testing and like activities. We
have a tendency to ignore hazards associated with tasks we consider
"safe".
Back at my old job, when I was surveying a 480-volt 250
amp molded-case circuit breaker, the worker I was with put his bifocals
up on his forehead so he could read the label on the breaker. He
dropped his glasses back to his nose and immediately the breaker blew
up! Luckily, he only had some red dots on his face and some singed hair,
as he was backing his head out when it let go. Metal droplets were
imbedded into the lenses of his glasses, but because of them, he wasn't
seriously injured. We investigated why that breaker might have failed
and never found a good reason; it was just time for it to fail. Carbon
buildup from earlier fault interruption, eroded contact materail that
gets sprayed up into the arc chutes, weakened dialectric due to the
extreme heating of arc interruption; all of these weaken circuit
breakers and could have caused what seemed like a perfectly good breaker
to fail suddenly. You never know.
4. Going to sleep during safety training
Nothing like a good nap to get you ready for a hard day's work! Every
Monday morning Shermco does a one-hour safety meeting for all
technicians. We call it the "Monday Moaner", because the technicians
really want to be at their job sites, not getting "preached to". We like
to do what we are comfortable with, even it there's a better way to do
things. Add that to the fact that wearing PPE and filling out forms are
port of the required steps, and fugettaboutit!
The other side
of the coin is that a lot of safety training is sooooooooooooooooo
boring! I've been to some sessions that, by the end, you're praying for a
mercy killing - either me or the instructor, I don't care which! Safety
training has to be focused, concise and interesting, otherwise everyone
tunes it out.
5. Using outdated or defective test equipment to troubleshoot.
When the leads are frayed or the meter's doggy, it's time to replace
it. I worked with a technician who used the same Wiggy (solenoid tester)
for seven years. You couldn't read the faceplate, the coil was so weak
that it didn't even vibrate and the leads had been pulled loose from the
bottom. Almost every time he used it he got nailed! One day, right
after he was shocked (for the kazillionth time) I said, "Hey, let me see
your Wiggy". He handed it down and I twirled it around my head and
smacked a concrete column with it. The coil came springing out and he
charged down the ladder like an enraged bull! I handed him my new Wiggy
and said, "Take this new one - that one's going to get you killed", to
which he said, "I've had that since I was an apprentice!" Don't get
emotionally attached to inanimate objects. If you really love your old
voltage tester, take it home and make a little shrine to it - just don't
bring it to work.
The NFPA committee was concerned enough to
put two different requirements for using only portable electric tools
and test equipment that were properly rated.
110.9(A)(1) Use of
Equipment, Rating states, "Test instruments, equipment and their
accessories shall be rated for the circuits to which they will be
connected".
Each of these statements are followed by a
reference to ANSI/ISA 61010-1, Safety Requirements for Measurement,
Control and Laboratory Use - Part 1: General Requirements for rating and
design requirements for voltage measurement and test instruments
intended for use on electrical systems 1000V and below."
6. Not wearing the right PPE.
No, I'm not repeating myself. Some people think that if they wear
anything by way of PPE, that should be enough. While it is true that the
injuries that you sustain probably won't be quite as severe as if you
didn't wear any PPE, there's a high probability that if the right PPE
was worn, you'd have no injury. This could also probably go under number
4, because if you aren't paying attention during safety training, you
probably can't choose the right PPE, either. Do you know how to
interpret arc flash labels? What do you do if there's no arc flash label
on electrical power equipment? Do you know how to use the tables in the
NFPA 70E? Do you refer to the notes when you use the tables? If you
answer "no" to any of these questions, you aren't choosing the right
PPE. As a matter of fact, you probably would not be considered qualified
by OSHA. Your company has the responsibility to provide training so you
meet OSHS's definition of a qualified electrical worker, but you have
the exposure to the hazard. It's your biscuits that'll get burned; you
need to do the homework to protect yourself!
7. Trusting someone else for your safety.
An OSHA compliance officer I know investigated an arc flash incident
where two electricians had been working together for years. The one who
was injured asked his buddy if the circuit had been checked and was
dead, to which his buddy replied, "Yeah". He really didn't think that it
had been done, but he didn't want to offend his partner, so he didn't
pursue the question. When he started working on it the circuit blew up,
causing severe arc flash burns. He stated, "If I had to do it over again
I would have checked it myself and not worried about so-and-so's
feelings". Actually, those weren't his words, but they won't allow me to
print what he really did say. You get the idea, though.
Sometimes relationships cause us to not follow through when we should.
Either we don't want to offend someone, like the above example, or we
don't want to look less than manly to our coworkers. "Nothing personal,
I'd just like to make sure I don't get my face blown off." However you
want to put it, don't neglect to prove systems dead personally.
8. Not performing required maintenance of power system equipment.
Too often companies look at maintenance costs as an overhead expense.
Nothing could be further from the truth. The problem is, it's difficult
to put a savings on things that don't happen. unscheduled outages, loss
of production, buying equipment at premium pricing, overtime, disposing
of the cratered equipment, etc. Those of us who've been through the
maintenence wars have seen the costs associated with neglect, but for
newer managers and accounting types, it's really difficule to
appreciate. Liken it to automobile maintenance. You go out and buy that
new ZR1 and then do no maintenance for 100,000 miles. What condition do
you think it will be in?
9. Not carrying your gloves with you.
During my safety training classes I like to ask how many people
actually carry their rubber insulating gloves with them? Maybe one or
two will raise their hands. Well, guess what, if you don't carry them,
you aren't using them. This might go along with thinking low voltage
won't hurt you. We get buzzed and it's no big deal. At the beginning of
2008 in Athens, Texas three TXU workers were working on a 120/208 volt
transformer. One of the workers stood and said, "Well, boys. Looks like I
got bit again", took three steps and was dead. Carry your gloves and
use your gloves, always.
10. Not using an Energized Electrical Work Permit system.
People tend to hate paperwork, including myself. This is one great
exception. OSHA wants us to plan each job, have the right tools and
equipment to do the job safely and follow our work plan. How do we
document the Hazard/Risk Analysis or our PPE Assessment? The OSHA Field
Safety Compliance Officers I know all tell me the same thing; if it's
not documented, you can't prove that you did it. The Energized
Electrical Work Permit provides the means to plan the work, assess the
hazard and the risk, choose the proper PPE for the job and document it.
The side bar shows an example of Energized Electrical Work Permit and
has a brief description of each section and its purpose.
Summary
There's always something else that could be included in this list, but
10 gets you thinking. We go through life making small mistake after
small mistake and nothing happens, until we happen to get the wrong
alignment of small mistakes and we now have an accident. Once the
accident starts, we have no control over it, so the best thing to do is
to avoid the small mistakes and tighten up the way we work.