Brady Arc Flash Labels Catalog Page

Arc Flash Labels

Arc Flash Safety

What is arc ash and what causes it?

An arc flash is a short circuit through air that flashes from one
exposed live conductor to another conductor or ground. This
electrical fault can create a dangerous release of energy, including
thermal energy, acoustical energy, pressure wave or debris.

There are many ways an arc flash can occur, including:

• Close proximity of a high-amp source to a conductive object

• Dropping a tool or creating a spark

• Breaks or gaps in insulation

• Failing equipment due to use of substandard parts, improper
installation or even normal wear and tear

• Dust, corrosion or other impurities on the surface of the conductor

What impacts the size of an arc ash event?

Common variables that impact the size and energy
of an arc flash include:

• Amperage

• Voltage

• Arc gap

• Closure time

Arc Flash Labels

• Distance from arc

• Three phase vs. single phase

• Confined space

Did You Know?

Anything above 50V that could be worked
on while energized ,resulting in exposure to
electrical hazards, requires an arc flash label.

Examples include, but are not limited to:

• Switchboards

• Panel boards

• Motor control
centers

• Industrial control
panels

• Meter socket
enclosures

380

NFPA 70E Standard for Electrical Safety in the Workplace

OSHA cites and fines employers for failure to protect employees
from the dangers of arc flash under regulation 29 CFR 1910.333(a).
The National Fire Protection Association (NFPA) details how to
comply with this regulation through the NFPA 70E standard.

According to the NFPA 70E standard, there are six primary
responsibilities that facilities must meet, including:

1. Training for employees

2. Written safety program in place that is actionable

3. Personal protective equipment (PPE) available for employees

4. Insulated tools

5. Arc flash hazard degree calculations

6. Properly labeled equipment

Most recent updates (2018)

The NFPA 70E gets updated every three years.
Some of the most recent updates include:

• Updated training and retraining requirements

• Revision to arc flash warning label content

• Elimination of the PPE hazard category 0

• Elimination of prohibited approach boundary

• Additional boundary requirements

• Revisions to selecting appropriate PPE

• Minor terminology changes
(such as work shoes now referred to as footwear)

What is an arc ash boundary?

An arc flash boundary is the distance at which an electrical
arc can flash outward and endanger employees working on
electrical equipment.

Additional boundary requirements include:

• Conductive articles of jewelry and clothing: Watchbands,
bracelets, rings, key chains, necklaces, metal frame
glasses, etc. shall not be worn within the restricted
approach boundary

• Working space: Space shall be kept clear and not used
for storage to permit safe operation and maintenance

• Barricades: When the arc flash boundary is greater than
the limited approach boundary, barricades shall not be
placed closer than the arc flash boundary

• Insulated tools: Employees shall use insulated tools
when working inside the restricted approach boundary of
exposed energized electrical conductors.

Arc Flash Labels

1. Exposed / energized conductor or circuit part

2. Restricted approach boundary

Distance where there is an increased
likelihood of electric shock

3. Limited approach boundary

Distance where a shock hazard exists

4. Arc ash boundary

Distance from an arc source where the
thermal energy exposure could cause
2nd degree burns on unprotected skin

Arc Flash Risk Assessment

The NFPA 70E 2015 edition requires employers to conduct an arc flash risk assessment to determine the amount
of thermal energy that could be generated from an arc flash incident. The information is then used to define a
flash protection boundary around the potential source, and to determine the level of arc-rated apparel and other
personal protection equipment required when employees cross the boundary while they work on or near explosive
live parts.

At minimum, the safety program needs to be audited at intervals not to exceed three years
and arc ash risk assessments shall be periodically reviewed at intervals not to exceed ve years.

Arc Flash Labels

Who should perform arc ash risk assessments?

Completing a best-in-class arc flash risk assessment in-house requires time, resources and analysis software to
accurately calculate arc flash risk. In addition, simple miscalculations can lead to incorrect incident energy levels
resulting in the improper use of PPE.

Brady’s Arc Flash Risk Assessment Service, performed by a licensed electrical engineer using power system
analysis software, enables you to not only reach compliance, but maintain compliance. Additional services also
include Arc Flash Audits and Arc Flash Safety Training.

381

381