It's been nearly 12 years since industry standards for personal protective equipment (PPE) outer apparel were published, and significant and continuous progress has been made ever since. Flame-resistant or flame-retardant (FR) rainwear is now available in dozens of sizes and a variety of colors and designs, but one challenge remains: comfort. Along with protective requirements, most linemen would like rainwear that is lightweight, nonrestricting and comfortable to work in; most importantly, linemen say they want rainwear that breathes.
Rainwear of the Past
A decade ago, contractors and utility linemen converging on a site for storm restoration could have been wearing any one of 12 different interpretations of rain gear, anything from a lightweight polyurethane, like a windbreaker, to a more durable PVC-coated/nylon-fabric-blend jacket or an industrial-grade polyester coat, or other pure-nylon outerwear with water-repellent qualities.
All of these fabric designs had a dangerous commonality: They melted when exposed to an arc flash. Needless to say, when safety-apparel standards (ASTM 1506-2000) were written and rainwear-specific requirements (ASTM F1891-01) were spelled out, all of these industrial-grade garments went away.
Manufacturers responded and several blends of new fabrics began to emerge. Kansas City Power & Light Co. (KCP&L; Kansas City, Missouri), as part of its protective-apparel program, began prohibiting clothing made from acetate, nylon, polyester or rayon, either alone or in blends. Storeroom-issued shirts, coveralls, coats, hoods and face shields made of 100% aramid fiber became standard. Each lineman was furnished with a quota of shirts and coats, which the utility replaced as needed.
Some utilities determined that the use of 100% natural (cotton)-fiber clothing was acceptable. Other utilities accepted the use of FR-treated natural-fiber clothing, while still others stipulated only the use of FR synthetic-fiber clothing. Depending on the fabric rating, FR rainwear does not provide a protective shield against arc flash. Simply stated, like all safety-coded shirts and pants, it is classified to be flame resistant if it does not melt and drip when exposed to an arc flash.
Survey results on rainwear among Kansas City linemen have been consistent with those in other parts of the country. Linemen just want to stay dry while wearing gear that does not restrict them from getting their work done. KCP&L linemen want outerwear that is cool to wear, lightweight, nonrestricting, durable and fitted, in that order of priority.
Manufacturers today offer a variety of colors, sizes and styles, but it has been more difficult to design garments that are lighter weight and cool to wear. Blending new fibers such as Nomex and Kevlar, and incorporating arc-FR buttons and zippers into a waterproof garment has been a daunting task, not to mention incorporating easily accessible pockets for radios and flashlights. Some linemen also prefer a stowaway hood or a storm-flap front. These are reasonable requests, but difficult to engineer into a garment.
Durability is a hassle for linemen and a cost issue for the utility company or contractor. When a garment is punctured or torn, it does not meet FR standards and needs to be repaired or replaced.
KCP&L linemen report that their rain gear is most commonly damaged by truck storage doors, briar patches or tree limbs during storm restoration. The corner of a steel cabinet door can destroy a brand-new coat. Working in rural areas where access to poles and line requires tracking through a patch of thorns and thistles can shred a garment. And during storm work, linemen are exposed to tree limbs and splintered wood poles and crossarms that can puncture a raincoat, violating the FR integrity of the garment.
Linemen are aware of these hazards and try to be careful, but they don't want to be restricted from doing their job just to avoid tearing their rainwear.
By far the biggest hassle for linemen working in the rain is the heat and humidity that often comes with it. Summer heat in Kansas is notoriously humid with temperatures exceeding 90°F. A lineman will tell you, “When I'm working in the rain all day and it's over 90°F, the coat is coming off.” The problem with traditional rainwear is that it does not breathe. Linemen become soaked from head to foot, not because of the rain, but because of the perspiration.
All-Weather Outerwear Field Trail
For linemen in Georgia, heat and humidity can be a factor for up to six months out of the year. Georgia Power Co. (Atlanta, Georgia) conducted a one-year trial of new garments that NASCO (Washington, Indiana) was developing.
The NASCO Super Suit, as it was nicknamed, is made of an all-weather/all-season breathable fabric that is flame and arc resistant. The ultimate goal was to replace currently used FR rainwear and FR winter outerwear with a breathable, flame- and arc-resistant all-weather/all-season system. The company also incorporated removable liners and a hood that would easily fit over a hard hat, and bib coveralls or pants into the design of the Super Suits.
During the research and development stage, several fabrics were identified and several material design combinations were prototyped. Most of them were too expensive and too stiff and inflexible to wear. For the field trials, manufacturers also developed a program to inform and educate each work group about the garments and progress during the wear trial. This included field-evaluation forms developed by Georgia Power and the vendors that measured the value of each suit to the linemen. Participants were issued 12 garments and asked to wear them in each and every possible work situation.
Georgia Power's testing revealed positive results.
The comfort goal was not only met but exceeded. Test results revealed that moisture vapor transmission rate (MVTR) values were above 10,000 g/m2/24 hours. In fact, after the garment was laundered five times, the MVTR values exceeded 15,000 g/m2/24 hours.
The protection goal was also exceeded. The arc rating was 7.7 cal/cm2. The material also passed all of the physical requirements of ASTM F1891. Additionally, further testing confirmed that it offered protection against flash fires (ASTM F1930) for gas utility workers who may be exposed.
The versatility goal was realized. Workers in the trial group wore the garments in storms, cool and cold weather, and summer heat. The garments proved effective in all of these conditions. In fact, other products currently being issued, such as military and recreational rainwear, were set aside in favor of wearing the one garment.
The Cost Issue
Utilities have watched these trials closely, but have been reluctant to purchase the more comfortable rainwear because of the cost. The price tag for a more breathable, lightweight all-weather/all-season system ranges from $500 to $600, depending on pockets, options and other preferences. But when rainwear is managed as more than a storeroom-issued garment, the higher price tag can be justified. In fact when managed like rubber gloves or other safety-issued garment programs (inventoried and issued with care), the more expensive all-weather/all-season garments actually can save the utility money compared to programs that provide both “on-demand” rainwear and winter outerwear FR clothing.
Georgia Power had to face this cost issue during its FR rainwear trial. The initial 12 suits for the wear trial were jointly provided with funds obtained from the company's FR clothing program. After the successful results of the wear trial, the company had to evaluate how the new Super Suit would be incorporated into its current FR clothing program.
First, the actual costs of the on-demand issuance of rainwear over a three-year period were estimated based on the number of rain suits used per year, the cost of the rain suits and the number of employees using rain suits. The cost of supplying winter outerwear was also calculated over the same three-year period. Since the Super Suit was to function as an all-weather/all-season system, both costs were combined to estimate the then-current three-year costs for the rainwear and winter outerwear programs.
The three-year increment used for these estimates was based on a projected three-year life for the Super Suit. The projected cost of the Super Suit was compared with the cost of supplying the currently used rainwear and winter outerwear. Over a three-year period, the results of the cost estimates indicated that Georgia Power would be saving money by switching to the more comfortable FR Super Suit. Most of the Super Suits from the original trial are still in service. This additional longevity of the Super Suit also contributed to the argument for the all-weather/all-season system.
KCP&L has approached the more-breathable FR rain gear in a similar manner. When the utility conducted its most recent FR rain-gear review, it evaluated products from NASCO and other vendors. KCP&L specified best pricing, a pocket on the pant leg and KCP&L's logo on the back of the coats. Only OSHA “electrically qualified” employees are issued the more-expensive FR rain gear, and the number of units issued is controlled because of the high cost. KCP&L has kept these sets of rain gear separated from the routine rain gear and under the management of the safety department.
Since the end of the Georgia Power wear trial, the Super Suit has been branded MP3, which is an acronym for multiprotection trilaminate, made from Southern Mills' Nimbus material. The favorable feedback has resulted in Georgia Power specifying the MP3 FR all-weather/all-season system for purchase for troublemen, field-service representatives and cable locators.
The next frontier for breathable, lightweight rain gear is making them traffic-safety compliant. For many, this is not a problem. Workers are used to putting on an FR traffic vest over their work clothes. Across the country, a handful of utilities, including Southern California Edison and Pacific Gas & Electric, have purchased the more expensive but comfortable FR rain gear for the same reasons and with the same controls mentioned previously.
If it's raining and work has to be done, most linemen, troublmen and meter readers will pull out their FR rainwear, issued from the storeroom to stay dry — inside and out.
Steven Gilkey is the director of field operations at Kansas City Power & Light. Gilkey has more than 23 years experience in utility operations, and holds a BSEE degree from Syracuse University and an MBA degree from Rensselaer Polytechnic Institute. Steven.Gilkey@KCPL.com
Jim Lancour is a safety and health consultant in the Southeast. He was a safety and health consultant with Georgia Power Co. prior to retiring after more than 25 years of service. firstname.lastname@example.org