Electrical Hazard Assessment: First Step in Meeting OSHA Standards
A hazard assessment engineering firm can help meet OSHA standards and improve safety.
- By Larry Altmayer
- Jul 06, 2007
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-
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.
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.
6. The firm must be able to create electrical one-line drawings
and then build a computer model using commercial software for
short circuit current flow and coordination. To do so effectively,
the firm must have not only the technical library with which to
model short circuit characteristics of existing equipment, but also
the knowledge and ability to evaluate available short circuit currents
for equipment not included in such a library.
7. The firm should be experienced with widely used electrical
data management and analysis software packages on which your
company may have standardized.
8. The firm should understand the impact of the electric
utility feeding the plant. Arc flash calculations start with available
short circuit current, which can increase or decrease depending
on actions by the utility. Ideally, the firm should do its calculations
with multiple assumed values of available short circuit current
so that future actions by the utility will not be a factor. At
the same time, the firm should be prepared to provide services to
keep the facility in compliance as inevitable changes are made to
the electrical system.
9. The work does not end with the electrical hazard assessment.
The firm must be prepared to create recommendations and concrete
action plans to lower hazards and correct deficiencies. Typically,
these recommendations would include changes to fuse types,
breaker settings, equipment repairs, adjustments to correct
improper interrupting capacity of protective devices, suggestions
to improve overcurrent coordination problems, and any other recommendations
that could reduce or eliminate hazards or the need
for PPE and fire-retardant clothing.
Resources and Expertise
Select an engineering services firm that has adequate personnel
and resources to handle the entire assessment project for the size
of your facility and scope of work needed, including employee
training and implementation of corrections. The firm should have
both electricians and engineers on staff. These resources should be
in close proximity to your facilities to avoid excessive travel costs.
Because your company is liable when anyone works in your
plant, the assessment firm must show that it can gather data safely.
This includes a written protection plan for gathering data while all
systems are energized and documented proof of its own workers’
safety training in equipment and tool usage. These plans and work
practices must adhere to NFPA 70E guidelines and OSHA rules.
It is a good idea to ask the firm to provide copies of typical documents
(customer names removed) associated with recent hazard
assessments as proof of experience. These should include detailed
study results and recommendations.
NEC recognizes arc flash hazards and recently issued
warning label requirements that are supported by OSHA. Your
assessment firm should be capable of producing equipment
hazard labels in house and in volume. To avoid the possibility of
label installation errors and increased liability, the firm should be
willing to install those labels.
Choose an engineering services firm that can follow up an electrical
hazard assessment with employee safety training and continuing
audits, using dedicated, experienced trainers on staff. Topics
covered during training should include:
¦ standards that govern electrical work and their requirements,
including NFPA 70E and others
¦ electrical safety work practices, including lockout/tagout
procedures per 29 CFR 1910.147
¦ applicability of other OSHA rules and penalties for noncompliance
¦ the difference between “qualified” and “unqualified”
workers and work limitations for unqualified workers
¦ comprehensive examples of acceptable and unacceptable work practices, including those in wet or damp locations
¦ use of key interlocking systems
¦ identification of type and level of hazards, including
electrical shock and arc flash
¦ identifying energized components and conductors
¦ determining nominal circuit and equipment voltages
¦ the use of voltage sensors and meters
¦ interpreting hazard warning labels
¦ safe approach distances to exposed electrical conductors
¦ rules for authorized “hot work” and use of Live Work
Permits and Job Briefings
¦ the consequences of poor electrical safety practices to
people and equipment
¦ PPE requirements, including selection, proper use, and
¦ required and recommended maintenance and safety
¦ grounds and grounding.
All of this training should include appropriate job aides. Furthermore,
it should be integrated with the employer’s standard
operating procedures and policies of enforcement.
General Business Considerations
Look to partner with an engineering services firm that has been
in business long enough to have established a good reputation.
The firm you select should be prepared to commit to a fixed cost
proposal and fixed timeline.
Ask the prospective assessment firm to provide customer references
that attest to successful completion of the entire scope of work.
This should include data collection, one-line drawings, detailed
short-circuit current coordination studies, electrical hazard analysis,
and NFPA 70E training. Verify this with calls to those references.
The firm should guarantee that its assessments will be
reviewed and signed by a Professional Engineer and that this P.E.
is licensed in the state where your facility is located. This is
required by law in most states and is a moral imperative because
of the life safety issues involved.
As a minimum, the assessment firm should carry general liability
insurance and professional liability insurance (errors & omissions)
and should be able to provide immediate proof of same. A delay in
providing such proof may well indicate that the firm is obtaining the
insurance just for you and may have been lacking it on previous projects.
It is also a good practice to examine the firm’s track record with
regard to insurance claims during the past five years.
This article originally appeared in the July 2007 issue of Occupational Health & Safety.