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Understanding Arc Flash PPE Categories

3 min read

An arc flash is one of the most dangerous events that can occur in the workplace. It occurs when electricity has a path of reduced resistance outside of the cables or systems where it is intended to be to another location. The electricity ‘jumps’ from the wiring to another object through the air. This generates a massive amount of heat and can also cause serious damage or injury to anything in its path. Arc flashes are often accompanied by explosions due to the high amount of energy that is being released.

In most situations it is not possible to predict when an arc flash is going to occur since it is not an intended result of a normally operating system. For this reason, anywhere that has high voltage systems in operation should be considered high risk for an arc flash. While these areas should generally be avoided by workers, sometimes it is necessary that they enter them. When this is the case, those entering the area need to be using the proper personal protection equipment (PPE).

Types of PPE for Arc Flash Protection

There are many different types of personal protection equipment that can be used in the workplace. Choosing the right types of PPE to provide protection against an arc flash is very important. The specific things that are necessary will depend on a number of factors including how high the voltage in the area is, the risk of an arc flash, and more. The following are some of the types of PPE to consider:

  • Face Protection – A face shield that is rated for arc flash protection will help to avoid burns as well as injury from flying debris.
  • Head Protection – A safety helmet or other type of head protection is critical for avoiding injury from the flying debris. This piece should also help ensure the electricity is not able to travel through the helmet into the person wearing it.
  • Hearing Protection – Arc flashes can be extremely loud. The fact that they occur suddenly makes the risk to hearing even more pronounced. Wearing strong hearing protection is essential in any area where an arc flash could occur.
  • PPE Clothing – The pants, shirt, and other clothing being worn should be rated for arc flash protection. If it not, the person entering the area should put on protective clothing over their other clothes or change into something that will keep them safe.
  • Eye Protection – If a situation does not need full face protection, wearing eye protection is still a good idea. Eyes can be especially vulnerable to electricity and flying debris can cause serious damage.

In high risk areas it is recommended to wear a fully body protection suit. This will provide as much protection as possible to anyone who is entering an area where an arc flash can occur.

Arc Flash PPE Categories

It is not enough to just look at the types of personal protection equipment and choose the items that are needed in a given situation. Each piece of PPE also must meet the needed protection levels based on the risks associated with an area. PPE that is used for arc flash hazards are broken down into four categories based on the level of protection that it provides. The four PPE categories are:

  • Category 1 – Equipment that has a minimum arc-rating of 4 cal/cm2
  • Category 2 – Equipment that has a minimum arc-rating of 8 cal/cm2
  • Category 3 – Equipment that has a minimum arc-rating of 25 cal/cm2
  • Category 4 – Equipment that has a minimum arc-rating of 40 cal/cm2

The higher the category, the greater the protection that it is able to provide. In most cases, this means that the material used in the PPE will be thicker so that it provides additional levels of protection. Along with the higher category level, additional types of protection are needed as the hazard level increases. For example, when using category 1 PPE there is generally no need to wear a protective hood that covers the neck and back of the head. When moving into category 3 and above, it is typically necessary to have the whole body covered because of the higher level of danger.

Personal Protection Equipment is a Last Line of Defense

Whenever discussing workplace safety, and especially safety with regards to arc flashes, it is important to remember that PPE is a last line of defense. In an ideal world, the PPE would never actually need to be used because the other steps used for workplace safety would be effective. For example, if someone needs to enter an area where there is high voltage equipment, the first option should always be to turn off the electricity at the source and use a lockout tag-out procedure to ensure there is no risk of electrocution.

In many situations, however, the other steps associated with increasing the safety of an area are either not possible, or not entirely effective. Having the right personal protection equipment will help to minimize the danger should all else fail.

What is Arc Flash PPE?

2 min read

arc flash PPEArc flashes are one of the most dangerous electrical hazards in the workplace. The damage to human health can be severe and permanent, from hearing loss to skin burns, and the sudden occurrence of an arc flash may even result in death. Employers will need to assess their facility for arc flash hazards and implement safety measures accordingly.

In addition to engineering and administrative controls, it is important to keep workers safe with personal protective equipment (PPE). Although PPE is considered the last line of defense, arc flashes occur unexpectedly and the consequences of a worker lacking PPE can be serious. When it comes to stocking your workplace with arc flash PPE, you will want to conduct an arc flash hazard analysis to get the right information (such as arc rating) for choosing garments and personal equipment. It should be noted that OSHA requires employers to provide PPE at no charge to employees.

When it comes to arc flash, the PPE used is based on the arc flash rating. Arc flash ratings constitute PPE categories, with Category 1 being the least harmful and Category 4 posing the highest risk and requires the most protective gear. Whatever the PPE category is, arc flash PPE will always include the following:

  • Eye Protection: Arc flashes produce extremely bright flashes that can cause permanent damage to a worker’s sight or eyes. Therefore, eye protection is essential. Safety goggles are used for the first and second category, while safety goggles are required for Category 3 and 4.
  • Hearing Protection: The sound of an arc flash explosion can be deafening with the potential to exceed 160 dB (for reference, a jet plane take off registers at 120 dB). Ear plugs are required by NFPA to be worn in all arc flash zones.
  • Shirts/Pants: Any exposed skin must be covered. The heat and light emitted by an arc flash can destroy and skin and tissue. It can be extremely painful and may cause long-term chronic pain and scarring. No matter the category of PPE, all garments must be arc-rated, and arc-rated shirts and pants are required for all four categories. However, Category 2 calls for an arc-rated jacket, and both Category 3 and 4 include arc-rated suit jackets and pants.
  • Foot/Hand Protection: Leather footwear (typically boots) is the standard for arc flash protection because of their nonconductive properties. The same goes for safety gloves, as leather gloves are used. When reaching the more dangerous levels however, arc-rated gloves are required.
  • Head Protection: Head protection is used in addition to hearing and eye protection. Depending on the category, approved and required protection includes hard hats and arc-rated flash suit hoods.
  • Face Protection: Included in exposed skin that must be covered is the face. If an arc-rated flash hood or other protection does not already include face protection, workers are required to wear an arc-rated face shield or an arc-rated balaclava.