ARC Flash Analysis

What is an ARC Flash?

An arc flash is a current flowing through air that flashes from one exposed live conductor to another conductor or to ground. When an arc flash happens, the temperatures can reach up to 35,000 degrees Fahrenheit. This is four times the temperature on the surface of the sun. The result can be destruction of equipment, fire, and injury.

What causes an ARC Flash?

An arc flash occurs when electrical clearances are reduced or compromised by deteriorating insulation or human error. The arc flash follows a conductive path between two hot (energized) wires or between a hot wire and ground.

Why is an ARC Flash Analysis important?

Without an arc flash study you will not know the actual level of danger or the appropriate personal protective equipment (PPE) required for employees. Electrical systems are dynamic and change over time. Internal changes, such as adding new equipment can affect the level of arc flash energy. A study must be updated every time the system changes. External changes, such as a utility changing transformers or changes at your utilityʼs closest sub-station can severely impact your level of arc flash energy.

Here are the facts…

The Federal Government (OSHA requires that all “Non-Dwelling” facilities have an ARC Flash Hazard Analysis done to determine:

  • The Arc Flash Boundary
  • The Level of PPE Required
  • The Presence of a Flash Hazard
NFPA 130.7 (E) says this:

“Safety signs, safety symbols, or accident prevention tags shall be used where necessary to warn employees about electrical hazards that might endanger them. Such signs and tags shall meet the requirements of ANSI Z535…”

NFPA 70E 130.3 says this:

“An arc flash hazard analysis shall determine the Arc Flash Protection Boundary and the personal protective equipment that people within the Arc Flash Protection Boundary shall use…”

NFPA 70E 400.11 says this:

“Electrical equipment, such as switchboards, panelboards, industrial control panels, meter socket enclosures, and motor control centers, that are in other than dwelling occupancies, and are likely to require examination, adjustment, servicing, or maintenance while energized shall be field marked to warn qualified persons of potential electric arc flash hazards. The marking shall be located so as to be clearly visible to qualified persons before examination, adjustment, servicing, or maintenance of the equipment…”

Refer to:

OSHA 29 CFR Part 1910.302-308 & 1910.331-335
US Department of Labor, occupational Safety & Health Admin
National Fire Protection Association, NFPA 70E


These are the types of violations that may be cited and the penalties that may be proposed:


A violation that has a direct relationship to job safety and health, but probably would not cause death or serious physical harm. A proposed penalty of up to $7,000 for each violation is discretionary. A penalty for an other-than-serious violation may be adjusted downward by as much as 95 percent, depending on the employer’s good faith (demonstrated efforts to comply with the Act), history of previous violations, and size of business. When the adjusted penalty amounts to less than $100, no penalty is proposed.


A violation where there is substantial probability that death or serious physical harm could result and that the employer knew, or should have known, of the hazard. A mandatory penalty of up to $7,000 for each violation is proposed. A penalty for a serious violation may be adjusted downward, based on the employer’s good faith, history of previous violations, the gravity of the alleged violation, and size of business.


A violation that the employer knowingly commits or commits with plain indifference to the law. The employer either knows that what he or she is doing constitutes a violation, or is aware that a hazardous condition existed and made no reason-able effort to eliminate it.

Penalties of up to $70,000 may be proposed for each willful violation, with a minimum penalty of $5,000 for each violation. A proposed penalty for a willful violation may be adjusted downward, depending on the size of the business and its history of previous violations. Usually, no credit is given for good faith.

If an employer is convicted of a willful violation of a standard that has resulted in the death of an employee, the offense is punishable by a court-imposed fine or by imprisonment for up to six months, or both. A fine of up to $250,000 for an individual, or $500,000 for a corporation, may be imposed for a criminal conviction.


A violation of any standard, regulation, rule, or order where, upon re-inspection, a substantially similar violation can bring a fine of up to $70,000 for each such violation. To be the basis of a repeated citation, the original citation must be final; a citation under contest may not serve as the basis for a subsequent repeated citation.


Failure to abate a prior violation may bring a civil penalty of up to $7,000 for each day the violation continues beyond the prescribed abatement date.


De minimis violations are violations of standards which have no direct or immediate relationship to safety or health. Whenever de minimis conditions are found during an inspection, they are documented in the same way as any other violation, but are not included on the citation.