What are different ratings of arc flash PPE?

When buying arc flash personal protective equipment, you will find that each item is rated differently. The ratings are based on how much protection they are able to provide. Tests are performed on the fabric or other material using a variety of different methods to see whether they can safely protect employees who use the PPE and are exposed to an arc flash.

Arc Flash PPE Categories

Arc flash personal protective equipment is rated in four different categories based on how much protection it provides. The levels are measured based on being able to protect the person wearing the PPE for a set number of calories per square centimeter worth of electricity in the arc flash. The following is the breakdown of the categories:

• CAT 1 – This level provides a minimum of 4 cal/cm² of protection.
• CAT 2 – This level provides a minimum of 8 cal/cm² of protection.
• CAT 3 – This level provides a minimum of 25 cal/cm² of protection.
• CAT 4 – This level provides a minimum of 40 cal/cm² of protection.

You can wear layers of PPE to expand the amount of protection that you will receive. For example, many people will wear an arc flash shirt and pants under an arc flash bib to get extra safety.

Remaining Careful

One risk associated with using any type of arc flash PPE is becoming too confident that the equipment will be able to protect you from harm. Employees wearing high-quality PPE may become careless because they feel that they are safe even if an arc flash does occur. The fact is, however, that no PPE can provide 100% safety from harm. An arc flash may be stronger than the PPE is rated for, or it may cause heavy objects to fly across the room, resulting in an injury to employees. Arc flashes can also start fires, which present additional risks to those in the area.