Heads Up and Hats Off With Foam Inserts
Dave Smith has been an Industrial Maintenance Electrician since 1975. He has taught maintenance, troubleshooting and safety courses to thousands of electricians in mines, mills, refineries, factories, plants, power stations and offshore platforms throughout North America and the Middle East. Dave is a hands-on guy and teache...
Hard hat manufacturers have developed Type II hard hats that provide both vertical and lateral (side impact) protection. Many of these hats use expanded polystyrene foam to provide the lateral protection, and a number of industrial companies and their safety departments are unilaterally mandating the use of Type II hard hats in all situations.
This has to be stopped when work is being done either within the Flash Protection Boundary or Limited Approach Boundary (FPB or LAB, whichever is furthest out) from exposed, energized electrical equipment.
I often hear people say either: “The hard hat will block the flash” or “The balaclava will protect my head from melting foam”. I find this amazing, as these claims invariably come from people with no scientific background or FR testing experience. Their statements are just opinions masquerading as fact.
The polystyrene in these hard hats can have a melting temperature as low as 240°C, and it doesn’t take much of an arc flash to generate a temperature like this. (The temperature of an arc fault can easily reach 5000ºC.) When this hard hat foam melts, it can drip through a balaclava and into your scalp. Only a team of professionals at the burn unit has a chance of being able to surgically remove it.
The reason that absolutely no one can make statements about the safety of foam inserts in hard hats is that no formal standard exists for testing them. This issue has been on the radar of the ANSI Z89.1 “Industrial Head Protection” committee for quite some time and, in mid-November, the ASTM F18.65 Technical Committee created a subcommittee “Taskforce for Di-electric Hard Hat Arc Flash Testing”. The committee comprises includes members from Hydro Quebec, Exelon Energy, First Energy, DuPont, Oberon, ArcWear.com and e-Hazard.com, and is chaired by Hugh Hoagland.
Hoagland is an original member of the IEEE 1584 committee (“Guide for Performing Arc Flash Hazard Calculations”), and has been involved with arc flash testing and standards creation for several decades. In short, his credentials are impeccable. One of Canada’s larger utilities hired Hoagland to conduct arc flash tests on a Type II foam insert hard hat from a major manufacturer (see sidebar, “Test Video”).
In lieu of an firm hard hat standard, Hoagland used ASTM F 2178 “Standard Test Method for Determining the Arc Rating and Standard Specification for Eye or Face Protective Products” to conduct the testing. When the hard hat failed, the utility informed the safety AHJ (authority having jurisdiction) that it would not conform to a Type II hard hat requirement within the FPB or LAB and, further, banned Type II hard hats for its electrical workers within these areas.
You must do this as well.
CSA Z462 “Workplace Electrical Safety” and NFPA 70E “Standard for Electrical Safety in the Workplace” are both very clear; all clothing and PPE (personal protective equipment) must not melt, so you must ban Type II hard hats within the FPB or LAB. As a worker, you are allowed to refuse dangerous work, and wearing Type II foam insert hard hats that have not been arc flash tested and certified while you work on exposed, energized electrical equipment is dangerous. Refuse.
If you have not had an arc flash study done (after testing to make sure your protective devices operate within specs), then you have no idea what, in fact, may happen during an arc flash. Make no mistake: when you pass the calorie rating of an FR material, it will ignite and burn. The result is one more electrical worker in the burn unit—or a body bag.
Until next time, be ready, be careful and be safe.
