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In Part 1 we discussed hard hats.

Part 2 we discussed "Daily Wear"

Part 3 will discuss Arc Flash Suits

As noted in Part 2, we typically recommend a two-category arc-rated clothing system such as that described below, daily wear on the left, additional arc flash protection on the right, i.e. an arc flash suit.

Technically NFPA 70E 130.5(G) Selection of Arc-Rated Clothing and Other PPE When the Incident Energy Method is Used allows you to stay out of an arc flash suit all the way up to a 12 cal/cm^2 arc flash hazard. However, if your facility practices the two-category arc-rated clothing system then that means your daily wear might only go up to 8 cal/cm^2. At this point, anything beyond your daily wear ATPV (arc thermal protective value) will require something of greater arc flash protection.

What is your facility's greatest arc flash hazard that might require electrical interaction? Some facilities only allow their workers to interact with electrical hazards up to 8 cal/cm^2. If this is your policy, then no suit is needed, you aren't allowed to work on this equipment... For everyone else, the question becomes, how much ATPV do you need in a suit? The answer should be based on what is the highest value of incident energy on your equipment's arc flash stickers and if working on such equipment is allowed.

Some of your equipment will be extremely dangerous, an example could be the main breaker fed directly from the secondary side of a main 2500kVA transformer. It is not uncommon to see arc flash values greater than 100 cal/cm^2 on this type of equipment. What type of work should ever be performed on this equipment? Arc flash suits are available higher than 100 cal/cm^2 but that does not mean work should be performed. It should be noted that arc flash suits will still protect an individual at this hazard, blast does not have a correlation to arc flash value, see this post for more information. Equipment subjected to this amount of arc flash will undoubtedly be destroyed, unplanned downtime and days, weeks or months of lost production will follow. Always consider the result of performing work at high arc flash values, this can help you determine your level of suit.

After determining the ATPV of your desired suit, you should also consider the environment the suit will be worn. If you are in a warm weather environment you may want a thin suit. EnesPro (now a part of National Safety Apparel) makes an incredibly thin feeling arc flash suit that offers high levels of arc flash protection. They also offer fans that connect to the hood to offer better air flow. If you are in a cold weather environment you may want to consider a thicker garment, Oberon and CPA are a couple of options. Many manufacturers make different "weights" of garments, they offer similar arc flash protection but some feel heavier than others, this is due to the material that is utilized. You may also want to consider the type of work, if you are always using the suit then ask the manufacturer about durability over time. The key is to shop around and purchase from a trusted supplier. National Safety Apparel, Oberon, Legion Safety, Salisbury, Grainger are all great options.

Hoods/Visors - Visor technology has also come a long ways in recent years. Be sure to consider the clearness and visibility of the visor in your arc flash hood when shopping. Some hoods have the ability to mount lights on the sides so you can see better. As mentioned above, hoods also have the ability for air flow fans mounting.

Maintaining your suit - Visors break easy, store your arc flash suit away from other items, i.e. hang on a wall or place in a locker to protect the suit. Keep storage away from harmful chemicals. Inspect for wear and tear and stains. Your suit should be clean and without holes, once you start to notice physical damage it is time to consider replacement, remember this is the last line of defense in an arc flash. Washing a suit can be performed just like many other arc flash garment, follow the manufacturers recommendation for laundering.