This December, the Occupational Safety and Health Administration (OSHA) renewed its ongoing partnership with Independent Electrical Contractors Inc. (IEC), an alliance that will see the two groups work together to provide agency staff with 70E and arc-flash training, as well as prevent worker exposures to electric shock and arc-flash hazards.

In this post, we'll take a closer look at some of these hazards, stressing not only how to identify high-risk conditions but also ways contractors can protect themselves from dangerous arc flashes.

OSHA defines an arc flash as occurring when "a flashover of electric current leaves its intended path and travels through the air from one conductor to another, or to ground." In the resulting phenomenon, temperatures can spike to more than 35,000 degrees with a fatal burn radius of greater than 10 feet. Every year, 30,000 of these arcs are reported, resulting in 7,000 burn injuries. 

According to OSHA, several of the most common causes of arc flashes include:

• Dust,
• Dropping tools,
• Accidental contact between electrical components,
• Condensation,
• Material failure,
• Corrosion,
• and faulty installation.

Because some of these hazards can be difficult to prevent, it is crucial to educate employees on methods they can use to protect themselves in the event of a flash.

Typically, the severity of the injuries levied on workers caught in an arc flash depends on their proximity to the event. In an effort to limit injuries, the National Fire Protection Association (NFPA) has developed specific approach boundaries designed to protect employees while working on or near energized equipment. While the sizes of these boundaries vary depending on the type of equipment being used, familiarizing themselves with the concepts can help workers better understand the hazards. These zones include the:

• Flash Protection Boundary: The furthest established area from the energized equipment is known as the flash protection boundary. If an arc flash were to occur, employees could still be exposed to a second degree burn due to the heat of the flash, but the effects would be curable.
• Limited Approach: Shock hazards exist within the Limited Approach area, meaning that contractors must take extra precaution when working at this distance from an exposed live part.
• Restricted Approach: The Restricted Approach zone exists inside the Limited Approach area, where the risk of shock is elevated such that workers should very rarely find themselves in such close proximity to the energized equipment.
• Prohibited Approach: Finally, the Prohibited Approach boundary exists around the equipment at a distance where an employee presence would be considered the same as making direct contact with the live port.

In addition to educating contractors on the risks of working inside these boundaries, construction site safety managers should also take strides to protect workers with a site-specific safety plan designed electrical safety in mind. These should include recommending best practices, such as de-energizing circuits, as well as using insulation, guarding, barricades and ground fault circuit interrupters to prevent exposure.

For more tips on how to mitigate the risk of electrical hazard at your workplace, contact Safety Advantage today.