Arc Flash: Know the Risks, Regulatory Requirements and Preventative Techniques

The definition of an Arc Flash according to the National Fire Protection Association (NFPA) is an electrical current that passes through air when insulation or isolation between electrified conductors is no longer sufficient to withstand the applied voltage.

Arc Flash incidences are such a health and safety hazard that there are multiple legal requirements associated with Arc Flash safety including work place owners responsibility to provide a safe working environment it is a legal requirement “Management must take the responsibility to provide a safe place of work and apply this philosophy / level of standard to the unique hazards of an Arc Flash” OSHA.

Arc faults are generally limited to systems where the bus voltage is in excess of just 120 volts, and with 5 to 10 arc flash incidences occurring every day in the US alone, makes Arc Flash an extremely relevant, important and in most instances a regulatory required issue that must be controlled.  An arc flash hazard exists if a person is or might be exposed to a significant thermal hazard. A significant thermal hazard is one with an incident (thermal) energy of 1.2 calories per square centimeter (cal/cm2) or more. Note that 1.2 cal/cm2 is considered to be the energy level necessary for onset of a second-degree burn.

OCS Group works closely with other industry experts, UL and the NFPA, to ensure the industry provides the best training ensuring safety amongst the workforce. OCS Group has developed an industry first competency based 8, 16 and 24 hour Arc Flash course to suit any level of knowledge and skills your company requires training for. This training is independent of your industry (Industrial, Energy, Utility, Renewable, Oil and Gas, or Equipment Design).

In this blog I have included a few facts as an introduction to the Causes, Dangers, Prevention and associated Standards relating to Arc Flash.

Image 1: Arc Flash Illustration (Courtesy of Westex and NFPA)

Arc Flash Lunch and Learn 14th February 2018 11am – 2pm (Houston)

Recently OCS Group provided our first Arc Flash course for 2018 and due to industry demand we will be providing a Lunch and Learn on this very topic at the OCS Group facility in conjunction with leading energy experts. The lunch and learn will include approximately 1 hour of presentations from multiple groups providing differing viewpoints of Arc Flash, and will be attended by BSEE, OSHA and the USCG. If you would like to attend

Please Call: +1 281 393 4704

Please Email:

Download Lunch & Learn Flyer


  • Industry Experts and Regulators
    • OCS Group
    • Aim Electrical
    • OSHA
  • Operators (Multiple)
  • Manufacturers

Dangers of Arc Flashes

  • Arc Flash can cause anything from minor injuries to third degree burns and death
  • The temperature of an arc flash can melt steel and exceed 20,000 DegC / 36,000 DegF
  • The sound is incredibly loud and deafening reaching levels of greater than 160DB
  • Arc Flash can cause hot, toxic vapors from vaporized metal
  • Arc Flash can spew molten metal and shrapnel large distances and can penetrate the body
  • The Blast pressure caused by an arc flash can be equivalent of a stick of dynamite launching victims tens of feet.
  • The Arc Flash is instantaneous giving no time for victims to get out the way
  • When materials vaporize they expand in volume (I.e. Copper will expand 67,000 times)
  • Arc Flash incidences can result in legal ramification, litigation fees, increase in insurance costs, fines, accident investigations etc…
  • Arc Flash can cause expensive and costly incidences destroying equipment, causing extensive downtime and resulting in costly replacement or repair of the equipment.


Image 2: Arc Flash Victim (Steve: The day of the Incident)

(Courtesy of Westex and NFPA

Image 3: Arc Flash Victim (Steve: 5 Days after the Incident)

(Courtesy of Westex and NFPA)

Causes of Arc Flash

  • Cause by anything that compromises the distance between energized components. For Example this could be;
    • A tool
    • Water bottle
    • Dust
    • Equipment Failure
    • Falling Tools
    • Accidental Contact
    • Using wrong test equipment
  • Failure to de-energize the equipment properly prior to working on the equipment in question.

Arc Flash Prevention and Safety

It is essential and important to note that personnel injuries resulting from Arc Flash incidents can be 100% eliminated by doing the following things;

  • Implementing appropriate safety precautions
  • Knowing and Utilizing industry knowledge and safe work practices
  • Wearing the appropriate and correct PPE for the situation

Tools, methods and safety to prevent arc flash injuries and fatal incidences are listed below;

  • Conducting an Arc Flash Analysis (On Land) is a legal requirement and must be performed prior to work being completed on energized equipment. This analysis determines the boundaries associated with the arc flash and the appropriate type and category of the PPE required when entering the differing defined zones.
  • Arc Flash resistant equipment is available, however this can be expensive.

Associated Arc Flash Standards and Responsibilities

  • “Management must take the responsibility to provide a safe place of work and apply this philosophy / level of standard to the unique hazards of an Arc Flash”
  • OSHA states that “The employer is responsible to assess the hazards in the workplace, and to select, have and use correct PPE”
    • 312(d) and 1926.28(a)
  • It is a legal requirement to document the risk assessment associated with Arc Flash.
    • 29 CFR 1910.132(d)(1)
  • Label Requirements as per ANSI Z535.4
  • Arc Flash Engineering Analysis needs to be re-conducted every 5 years OR when there has been any alterations to the equipment.

IF the legal requirements are not associated to your area of work, however an Arc Flash risk exists it is good practice to ensure that an Arc Flash Analysis is completed on all associated equipment and that employee’s service live, and it is imperative that the correct category of PPE is available for use when operating on such equipment.


Example of OCS Group Arc Flash Labels

Further Study and Information

OCS Group can conduct all of the following services to ensure you are compliant with your work place safety requirements, ensure it is a safe place of work and ensure your workforce is competently trained to be aware of Arc Flash safety and ensure correct precautions are utilized.

NOTE: Please check your local regional, state and federal Arc Flash legal requirements. OCS Group can provide this service for your local region.