Is Asking for '8 Cal' FR Clothing Enough?
Before you consider comfort or cost, fully understand the quality, consistency, durability, and level of thermal protective performance engineered into the flame-resistant fabric for the clothing you select.
- By Rich Godjics
- Dec 01, 2008
Understanding and protecting against arc flash and other electrical hazards and meeting the requirements of NFPA 70E has become more widely practiced in the past several years, and “8 cal” has become the industry standard for daily-wear FR clothing. This refers to the amount of protection from incident energy, expressed in calories per centimeter squared, that a fabric will provide in an arc flash exposure. It’s also expressed as an “ATPV” (Arc Thermal Performance Value) or arc rating.
The decision to select protective apparel with this arc rating makes sense. Since 2000, the large majority of companies already using protective clothing for potential arc flash exposures have set minimum arc rating requirements of 8 cal/cm2 for their daily wear, which then is typically supplemented with arc flash suits with higher arc ratings to cover the occasional higher energy exposures.How various companies arrive at this common solution is wide-ranging. Some companies take very elaborate steps to complete detailed fault current studies; others simply use, or initially use, the methods available in NFPA 70E to determine the level of hazard or risk and associated required levels of protection in PPE needed for various tasks to be performed on or near energized electrical equipment.
In either circumstance, by far the most common decision is to establish a companywide protective clothing policy around a minimum arc rating of 8 cal/cm2. The question then becomes, what more do you need to know about the 8 calories of protection you select? What else could contribute to or compromise a successful protective clothing program? The durability of the flame resistance after extended launderings, quality of the material, shrinkage control, and day-to-day comfort should be given serious consideration, as well as the cost per employee of the solution you ultimately bring into your company. Unfortunately, these considerations are often incorrectly treated as secondary in importance to the “8 cal” number that most safety professionals are chasing after.
What About the Fabric?
What is meant by this? Let me walk you through an observation. Every year, I participate as an exhibitor at the National Safety Congress’ safety show, which year to year is arguably the largest and most attended safety conference and exposition in the United States. Exhibitors look forward to this annual event with high expectations of significant foot traffic in their booths and the prospect of networking with various manufacturers and registrants.
At the 2008 show, thousands of registrants had the opportunity to visit with exhibitors from around the United States—and now, the world—who return to this venue every year with the expectation of generating new business opportunities. So exhibitors set up eye-catching displays sufficient to draw safety professionals into their booths or exhibits and then make their pitch or demonstration more directly, discussing the benefits of their product or service. These elaborate displays—possibly wrapped in high-end woods and constructed of sleek metals draped with catchy slogans— are abundant, created with the assistance of marketing agencies experienced in building a desired impression or image. Because the tag lines and slogans all look relatively the same, how does the attendee sort out the market-leading products or services from the followers?
Where the exhibitors have experience in creating a particular or appealing image, such as market leadership or as the market innovator, how does the attendee find and engage the true authority he intended to find to better understand a new OSHA regulation or imperative consensus standard requirement, such as NFPA 70E? At this show alone, hundreds and hundreds of individuals entered show displays during several days, looking for an “8 cal” solution. Once understanding the need or reason for the booth visit, most sales representative reasonably and routinely showed the portions of their various lines that meet this arc rating requirement and quickly discussed color options, cut of garments, stock and availability, delivery timelines, and estimated costs. Before returning to the show aisles, the attendee was handed product literature or gave the exhibitor mailing information so its literature could be received and reviewed at a later time. Is this an accurate and reasonable illustration of trade show booth interaction?
It is essential to recognize there is one critical factor commonly overlooked, as I’ve highlighted in this illustration.When you consider the existing arc flash standards and test methods are fabric based and that the most critical aspect of how protective the garment is also is fabric based, it is easy to realize the fabric should be the first “brand”decision the safety professional should make.However, this illustration does not contain an exchange about the critical information related to the engineering steps or technologies used to manufacture a consistent, durable, protective flame-resistant property into the fabric(s) used in garment construction needed to make an educated selection of protective apparel, before the other factors of color, availability, and costs are investigated.
Away from the trade show aisles, at work where manufacturers’ representatives make sales calls, through Internet surfing, or during garment catalog review, safety professionals can inadvertently skip this key assessment. All of us can understand when a safety professional makes the assumption that all new 8 cal/cm2 garments are relatively alike in their protective performance to arc flash because various garments with an 8 cal. arc rating have very similar insulative performance to the energy of an arc flash.However, the arc rating is not the complete account of the protective capabilities of comparative garments because fabric finishing consistency and proven performance of the engineering steps of each flame-resistant fabric being considered can be critical to the safety and wellbeing of the wearer. So the arc rating is not by itself a fair indicator of the success or failure of an arc flash clothing program.
Specifying a Fabric Brand
Several exhibitors at these large trade shows and distributors via the Internet and other marketing measures are showcasing not what I would characterize as competitive products, but flawed products and/or unproven products. Using the large marketing budgets described earlier, they are producing sophisticated and appealing messages with graphics and creative literature that has been cultivated to mimic the platforms and offerings of the market leaders. But their offerings do include options with arc ratings of 8 cal/cm2, and therefore they are making sales.
If you take a few moments to investigate the publicized story of Ergon Energy via the Internet, you will see this company’s firsthand experience where factors other than the garment arc rating contributed directly and detrimentally to its FR program. I therefore strongly encourage the consumer, or the health and safety representative investigating his company’s PPE options, to adopt the practices of those that have already implemented companywide, long-term successful protective clothing programs.
Here are some proven steps to this level of success: Further your due diligence and do not stop the FR fabric investigation once an option is said to meet minimum industry standards or the product has the 8 cal/cm2 arc rating determined to meet your needs. Separate the proven fabric performance and FR technology evaluation from the product’s associated marketing campaign.
Before you get to the steps of considering whether a product is comfortable enough or cost effective enough for your program, fully understand the quality, consistency, durability, and level of thermal protective performance engineered into the flame-resistant fabric for the clothing you select for the safety of your employees. It is wise for companies to create a detailed specification for the level of protection required and the fabric brand they have selected. Because the engineering technology for FR fabrics is so complex—especially that of FR cotton and cotton blend fabrics— there are many unseen variables that, if not properly handled, can cause serious problems and lead to significant additional costs downstream. Investigating and specifying a specific brand of fabric can help to ensure quality and consistency throughout all of your company locations.
Beyond the important 8 cal/cm2 arc rating, a safety professional who understands and specifies proven flame-resistant fabric manufacturers that can meet these additional performance requirements takes substantial steps toward building a world-class protective clothing program. Only then should begin the important but secondary steps to identify the more comfortable options in garment design and color options of which their employees will approve.
This article originally appeared in the December 2008 issue of Occupational Health & Safety.