Electrical Hazard Assessment: First Step in Meeting OSHA Standards
A hazard assessment engineering firm can help meet OSHA standards and improve safety.
OSHA has long required employers to
evaluate the workplace for electrical
hazards. Most employers are familiar
with possible shock hazards, but in recent
years, and with the publication of the 2004
edition of NFPA 70E, electrical arc flash
hazards are now being assessed and quantified.
Arc flash is accompanied by intense
heat and arc blast pressures that can cause
severe burns, concussions, falls, and associated
injuries. Moreover, these events are a
leading cause of death for qualified electrical
workers. Assessing the workplace to
identify these hazards is required by OSHA.
The U.S. Department of Labor estimates
that there are, on average, 9,600
serious electrical shock and burn injuries
each year. About 80 percent of these are the
result of arc flash events. According to the
National Safety Council, more than 1,000
deaths occur annually that are related to
electrical shock and arc flash. Fatalities
aside, about 2,000 electrical workers
require treatment in burn centers each
year, and burns result in more days of lost
work than most other injuries.
In 2005, OSHA assessed employers
more than $34 million in fines, 44 percent
of which were due to electrical hazards.
Several OSHA standards spell out
employer responsibilities in assessing the
workplace to identify potential electrical
hazards and protecting workers from them
with appropriate work practices and personal
protective equipment. However,
many company managers still don’t realize
that this assessment now must include arc
flash hazards. Failure to comply with
OSHA requirements puts workers at risk
and can result in fines and exposure to multimillion-
dollar lawsuits.
With the stakes so high, it is imperative
that companies assess their electrical infrastructure
and configuration, including the
equipment and work practices for all actual
and potential electrical hazards—especially
arc flash hazards. These assessments are
complex; unless you understand the special
expertise required, you risk falling short of
OSHA requirements. For example, the
sections of 29 CFR 1910 relating to PPE
selection are based on industry standards
such as NFPA 70E and IEEE 1584. These
standards are used to calculate heat energy
associated with an arc flash event based on
fault current, fault clearing time, and other
factors. Furthermore, the National Electrical
Code (NEC) mandates equipment to
have warning labels that clearly identify
electrical shock and arc flash hazards. Misconceptions
abound in the application of
all of these standards.
Because of such complexities, most companies
seek an engineering services firm to
perform a comprehensive electrical hazard
assessment of their facilities. Of course, this
entails the responsibility to make sure the
selected firm is qualified to perform the
work. The following sections outline important
tips on what to look for in selecting an
electrical hazard assessment firm.
Technical Qualifications
1. Select an engineering services firm
that is familiar with your type of facility,
processes, safety requirements, and
industry-specific requirements. What is
appropriate in one facility or industry may
not be appropriate in yours.
2. The firm must understand the intricacies
of all electrical safety standards and
their requirements—OSHA’s and others.
The firm must be able to articulate the pros and cons of the different methods required to do the assessment.
These standards would include 29 CFR Part 1910 Electrical Subpart
S, NFPA 70, NFPA 70E, IEEE 1584, ANSI, ASTM, and various
state and local standards (e.g., Cal/OSHA).
3. Ask prospective firms to tell you the common pitfalls of
doing an electrical hazard assessment and how to avoid them. If
they can’t articulate the common pitfalls, then they probably don’t
have the depth of experience you need.
4. Make sure the firm fully understands OSHA requirements
for documentation and recordkeeping. As far as OSHA is concerned,
if it wasn’t documented, then it didn’t happen. Failure to
keep proper records can lead to violations and fines.
5. The firm must have the expertise to provide an assessment
that meets the full requirements of OSHA and NFPA 70E. This
includes an analysis of all electrical equipment down to 50 V. The
firm must know the differences between IEEE 1584 and NFPA
70E calculations for short circuit currents and why it is often wise
to calculate using both methods to account for worst-case possibilities
and avoid having to redo a study in the future. Many firms
do only 240 V and above analysis or an “open book” analysis
using NFPA 70E tables only, disregarding the table usage
requirements and qualifications. Furthermore, the firm should
know the limitations of each standard; for example, IEEE 1584
cannot be used when available fault current exceeds 106 kA or
when voltages exceed 15 kV.
This article originally appeared in the July 2007 issue of Occupational Health & Safety.