After a decade of electric arc testing, incident investigations, and incident replications using electric arcs, a few lessons have emerged as critical in assessing a PPE program. What is the most overlooked part of the clothing mix?

Is the PPE being worn?

 The most protective items do no good if they aren’t being worn. If you aren’t auditing your program, you will never know this information. Audit, audit, audit. Annual audits should be the minimum. Building a strong safety culture which is “self policing” is best, but audits are still critical. Ask the end user why they aren’t wearing the PPE. It may seem too straightforward, but this is the easiest way to discover most real issues. Resolve issues like breathability with cross-vent style hoods, supplied air, PAPR devices or other ways to make the worker comfortable. Some companies don’t realize that HRC 2* work can be performed with an arc flash rated faceshield and a balaclava style hood such as a race car driver’s hood or a firefighter’s hood. Most are now arc rated at >8 cal/cm² meeting the HRC 2* requirement. W.H. Salisbury has an excellent study on this subject available for download www.whsalisbury.com or visit www.ArcWear.com for the study.

 Resolve other issues of overheating with frequent breaks, proper hydration, and consider use of cooling devices like cooling vests (make sure they are arc rated and have been tested in the range your workers are exposed to).

Are you overprotecting to be “safe” while causing issues with heat stress or worker compliance? Save the money and do the arc flash study. We often find a one day “quick study” doing basic hand calculations can give PPE minimums and may help you eliminate “over protecting.” A full study will provide a fault current and coordination study and recommendations to reduce arc energies to the point of saving PPE weight. Full coordination studies can also increase system reliability by providing selective coordination. Balancing selective coordination and arc flash energy is an art; an experienced study engineer with extensive design experience will save the company on many fronts over the long run.

 Are you buying the cheapest suit or the right suit for the job? The least expensive suits are heavier in weight than other suits and are a good value IF workers are wearing them for a short time such as routine switching for a few minutes. If your workers are working in flash suits more than 10-15 minutes per day consider a lightweight, highly protective suit from Steelgrip, NSA, or Workrite. Some of the other manufacturers have VERY lightweight suits which meet 40 to 65 cal/cm² and yet weigh in at less than half the common suits on the market. If you use a suit once a week for a few minutes to rack a breaker it might not make a difference, but if you wear the suits for more than about 10-15 minutes, you will see and feel the difference. Consider the cost AND the comfort to increase compliance. Adding venting technologies may add only $100 to the suit but it can also make a huge difference in worker comfort. Steelgrip, NSA, and Stanco all have well engineered vented suits with fans which provide excellent breathability and less fogging for a reasonable upgrade cost. Other options include PAPR type devices which can also filter air but in many cases are less effective in breathability and fog prevention. Field trial your choices to see how they perform.

Is it protective?

 Does it meet the minimum arc rating of the NFPA 70E tables or does it meet the minimum of your calculations? Again, overprotecting is a dangerous strategy since some safety factor is built into the arc rating initially and other factors such as heat stress and breathability are usually overlooked when choosing PPE. Don’t just look for the lowest price or the highest protection value. Think out all the factors for protection including worker acceptance and buy in. Including the workers in the purchase decision is the best way to get buy in and a team usually makes a better and less biased decision than an individual.

Does it meet the right standard(s)?

 FR is NOT FR all the time. FR Acrylics, FR nylons and FR polyesters are not really FR for most practical purposes. These materials should have another name because flame resistant by definition gives the end-user the wrong impression. They may be fine for a road worker who has little or no flame exposure greater than hot asphalt or a heater in winter but they are worse than useless in electric arc. Companies like NASCO, Neese, Rainfair and others sell truly arc resistant, highly visible rainwear meeting ASTM F1891 and ANSI 107. FR products should be avoided unless they meet these standards. For flash fire the NFPA 2112 and the ASTM F1891 are the only standards I trust for rainwear. In a roadway workzone, high visibility vests use CSA Z94 or ANSI 107, but be certain they meet ASTM F1506 or ASTM F1891. Other “flame resistant” standards are useless in electric arc.

• Clothing
• ASTM F1506
• Rainwear
• ASTM F1891
• Hoods and Faceshields
• ASTM F2178
• Fall Protection Exposed to Electric Arc
• ASTM F887-2004
• Gloves
• ASTM D120
• Flash Fire Clothing
• NFPA 2112, CGSB 155.20
• Insulated Tools
• ASTM F1505
• High Visibility Clothing
• CSA Z94 or ANSI 107

Did I think about everything? What about the pieces of PPE we take for granted?

Hardhats/hardcaps:

Class G vs. Class E hardhat? Class G is tested to 2400V while Class E is tested to 20,000V. Fiberglass can meet Class G but only much more capable materials can meet Class E. The additional issue with fiberglass are moisture and cracking issues compared to Class E. Know the differences and KNOW your applications. Avoid extras which can ignite and continue to burn such as polyester hairnets (melting FR or not) or ignitable hoods or cooling headwear which don’t meet the ASTM F1506 standard. There are items which meet ASTM F1506 for all these categories.

Rainwear

Here “flame resistant” (FR) is meaningless. Use only rainwear which complies with ASTM F1891 or NFPA 2112.

Gloves

Shock applications vs. Arc Only applications? Shock applications require voltage rated gloves meeting ASTM D120. These are rubber gloves and are most often from Salisbury, White Rubber or Comasec. If your application is arc flash only, then leather gloves or arc flash rated gloves which are less expensive are adequate. See NFPA 70E for suggested applications.

Ear Plugs vs. Ear Muffs

The ArcPlug from EAR™ minimum reportable threshold of ignition for ASTM F1958/1959 of >10 cal/cm². Igniting a plug in the ear is very improbable especially when wearing a faceshield and basically impossible under a hood, so most ear plugs would be acceptable. Plain EAR Classic™ ear plugs are almost impossible to ignite in electric arc while preformed plugs like Howard Leight are relatively easy to ignite when exposed to arc. Up to HRC 2, when no side of face protection is required, consider the Arc Ear™ Plug from Aearo or the EAR Classic™, both of which are above the minimum reportable threshold of ignition in <8 cal/cm² exposure. Ear muffs are also difficult to ignite but no full study has ever been completed on any of the major brands. NFPA 70E recommends inserts but the continuous hazard should receive preference in most cases.

Respirators

Pure silicone vs. webbed head adjusters. Pure silicone full face respirators, like those from MSA and 3M, have been evaluated in the past for specific users and these perform best. Using the webbed head adjusters available from some companies could be adequate if the webbing is Kevlar®. Have the product evaluated for arc flash or ask the manufacturer for their recommendations.

 Disposable coveralls

Most common disposable coveralls are NOT arc resistant. Softguard DTP®, Limited Use Nomex®, and FR Sontara® are the only three which have been evaluated for electric arc. Some chemical resistant coveralls are also arc rated but they should meet ASTM F1891 or ASTM F1506.

 Winterwear

This is probably the most overlooked issue in the industry. It still amazes me how many people thing an FR shirt UNDER a heavy flammable jacket will provide any protection. This is NOT the case. The fuel from an outer clothing from a spunlaced polyester garment like Tyvek to a winter jacket or rainsuit will cause at the least facial burns in an arc exposure. In many cases and in two accidents I have helped investigate the lightweight “FR” melting rainwear, and a heavy non-FR winter jacket burned the worker under their FR clothing to 60% body burn or greater. This is life threatening in most cases. New 3M FR Thinsulate is just coming on the market in FR winterwear but most name-brand products should be studied thoroughly by the safety department and the electrical safety folks. What seems good might not be. Winterwear which does not meet ASTM F1506 is inadequate for electric arc exposure.

 Shoes/Boots

Avoid ANSI compliant tennis shoes. Good leather shoes or boots or dielectric shoes are usually excellent performers in electric arc.

 Safety eyewear

NFPA 70E and the OSHA interpretation on metal eyeglass frames are different. Many companies forbid them but some allow them when they are prescription eyewear, and worn under a faceshield or a pair of goggles and secured to the face with a non-conductive device. Kevlar Chums are now available and these would not add to the extent of an injury and still hold the eyeglasses in place. NFPA 70E prohibits metal eyeglass frames in the 2004 version.

 Hairnets and Beardnets

EDSA arc flash calculation labeling software used to print out that hairnets and beardnets were not allowed in electric arc applications but this was before the Nomex® hairnets and beardnets became available from ArcStore.com and Salisbury. Now these applications can be FDA complaint AND NFPA 70E arc compliant. Cleanroom complaint hairnets and beardnets are also available from some manufacturers such as White Knight Engineering.

 Undergarments

Avoid the new wickable melting t-shirts and wickable meltable underwear like the bird flu! These materials are great for skiing on the weekend but should not be part of your undergarments in arc or flame situations. Plain old cotton, FR wool and silk are good options for winter undergarments. Silk is commercially available from companies like LL Bean while FR wool is available from Ullfrotte. Flame resistant bras and other undergarments are now fairly commonly available such as the ArcBra™ from ArcStore.com, but in order the meet the NFPA 70E standard workers are required to wear non-melting natural fiber clothing at a minimum. Some companies choose flame resistant bras due to the limited options of 100% cotton bras.

Simplify your NFPA 70E arc flash PPE program. Using daily wear of HRC 2 and adding an additional coverall (such as the Indura UltraSoft® 13 oz Sateen) or lightweight flash suit to take the system to 40 cal/cm² then adding a 40 cal/cm² flash suit hood makes a well rounded program easier to administer and manage. It makes the system lighter, less expensive and easier to work with. Think about how the workers will don the clothing. One lost time injury occurred when a worker fell down steps trying to put on a coverall. Perhaps a coat/chap/legging arrangement or a designated place to sit for donning and doffing would have prevented this accident. Picking a suit with zippers on the legs or with adequate openings will allow workers with larger feet to don the clothing quicker and make compliance easier. Balancing easy donning and adequate protection is an art. Some companies have excellent products which make donning PPE a joy. Others focus on their own liability or cost cutting and ignore the issue of worker compliance. Pick the strategy which works best for you and your workers; with your help the market continues to grow for creative, well engineered safety products.

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Hugh Hoagland with ArcWear.com, e-Hazard.com and ArcStore.com, is an arc flash consultant who performs arc flash hazard assessments and calculations, provides training, accident investigation, testing and other services related to electric arc exposure for companies around the world. Hugh may be reached at 502-314-7158 or e-mail him at hugh@arcwear.com.