↑ RETURN TO TOP ↑   The True Cost of a $40 Flame Resistant Shirt

 

↑ RETURN TO TOP ↑   Flame-Resistant Clothing Why you may need it, and how to be in compliance

 

You may be taking a first look or a closer look at flame-resistant (FR) clothing for a simple reason: Legal regulations and voluntary industry safety standards encompassing personal protective equipment (PPE) are becoming more exact and pervasive. NFPA 70E, a national consensus standard that establishes safety guidelines for workers exposed to electrical hazards, is a prime example. 70E is driving changes across numerous businesses and facilities where employees access electrical systems and energized components. Many sites contain a variety of electrical work hazards, illustrating the increasing call for FR clothing. When it comes to FR protection, you have to ask two questions: 1. Does my company have employees that need to be in FR clothing? And, if so: 2. How do we comply with industry regulation or standards? Two primary hazards FR clothing is designed to protect workers from two specific types of hazards: flash fire and electric arc flash. A flash fire is a rapidly spreading fire caused by igniting an atmosphere derived from hydrocarbon vapors of an ignitable liquid or finely divided combustible particles (e.g., coal dust or grain) in a concentration exceeding the chemical’s lower explosive limit. Temperatures can reach 1,000°F to 1,900°F. Flash fire is a primary hazard in industries that create a combustible material as a product or byproduct, such as petrochemical or metallurgy. An electric arc flash is the passage of substantial electrical current through ionized air, created by an electric fault. Typically lasting less than one second, an arc flash explosion generates extremely high radiant heat and releases acoustical energy, a pressure wave and molten debris. Temperatures can reach 35,000°F. Arc flash is an obvious concern at electrical utilities; however, exposed electrical equipment at 50 volts and above is the threshold that requires the use of NFPA 70E’s electrical safety practices. Most manufacturers have employees whose work falls under this description. Standards help Consensus standards play an important role in helping safety pros meet safety standards. While OSHA regulations focus on the “what” that needs to be done, industry best practices can provide companies the methodology for the “how” to address safety issues. For example, with electric arc flash type hazards you must perform a Flash Hazard Analysis of your facility. This is a difficult and often time-consuming job. It can be accomplished in several ways including the following:    • Have an inside electrical resource perform the analysis using NFPA 70E formulas. This includes a comprehensive evaluation of each electrical task likely to be performed. There is software available to assist, but you must have the data for each task to input.    • A second method is to match each of the electrical tasks to one of the task tables in NFPA 70E. Again, you must be knowledgeable enough to determine where your tasks match the tables    • A third alternative is to hire an outside expert to perform the analysis for you. This is the easiest and likely the most comprehensive action, but probably the most expensive.   Match hazard with clothing The process of correlating hazards to appropriate FR clothing often goes as follows: 1. Identify hazard type – either flash fire or electric arc flash. This review will not only determine the presence of potential hazards, but will guide your ultimate choice in FR clothing regarding materials, hazard ratings and product types. 2. Review the applicable standard for your hazard. There may be new standards applicable to your industry or the hazard present. Double-check. 3. Determine the level of protection needed. FR garments are rated based on the protection they provide, typically measured in calories (heat energy) applied per square centimeter of surface area. Using garments of insufficient ratings has understandably negative consequences. Conversely, using garments rated higher than your hazards dictate can subject workers to unnecessary discomfort and impose added costs on your company. 4. Research the various PPE offerings available to meet your needs. There are many different types of FR fabrics providing the foundation for finished garments. Garments themselves come in a multitude of cuts, colors and configurations. Comfort, durability, price and service support should be considered. 5. Evaluate the various garments through wear trials, peer references, safety committees, etc. Fabric manufacturers, garment manufacturers, uniform supply companies and others in the FR sales chain have plenty of data to help you decide. Safety organizations are also excellent sources of information. 6. Install an FR garment program in which the required PPE is made available for each affected employee. This can be either directly purchased by the employer and provided to the employees or rented from an industrial laundering company and coordinated by them. 7. Train employees on safe work practices and proper use of PPE. Applicable regulations & standards OSHA mandates that govern the use of FR clothing: General Duty Clause – Section 5(a)(1) of the Occupation Safety and Health Act of 1970 OSHA 1910.132 “Personal Protective Equipment” OSHA 1910.269 “Electric Power Generation, Transmission, and Distribution” OSHA 1910.335 “Electrical Safety Related Work Practices” National consensus standards that apply: NFPA 2112 “Standard on Flame-Resistant Garments for Protection of Industrial Personnel Against Flash Fire” NFPA 70E “Standard for Electrical Safety in the Workplace” NESC “National Electric Safety Code” ISHN Article May 24, 2007 by: Mark Saner © Workrite Uniform Company, Inc.

 

↑ RETURN TO TOP ↑   The Burning Question

Is 100 percent cotton protective in an electric arc flash? While lab tests say so, real life experiences say no! It is widely understood that clothing made from non-flame resistant synthetic fabrics, such as polyester, nylon and polyester/cotton blends, are not appropriate when working on or near electrically energized parts and equipment. If these garments are exposed to an electric arc flash, they can ignite, melt and drip, which can lead to severe contact burns to the skin. In fact, the OSHA 1910.269 and NFPA 70E standards prohibit this type of clothing. Many people, however, still consider 100 percent non-flame resistant cotton fabrics to be safe in an electric arc flash. The only thing safer about 100 percent cotton is that it does not contain a meltable component; it will ignite just as readily in an arc flash. In fact, cotton fabrics present major hazards in arcs; they burn hotter than poly-cotton, and are generally worn in slightly heavier weights. This means more fuel for the fire. Once ignition occurs, more fuel and a hotter fire combine to cause severe burn injury. Heavier fabrics generally require higher incident energies to ignite, and published ignition thresholds are often quite close to the oz/yd2 weight of the test fabric. This has led to policies that allow the use of 100 percent non-FR cotton (of >11 oz/yd2—typically denim jeans), where hazard analysis has determined arc energies are well below eight calories. While at first glance this may seem reasonable, the logic is predicated on two conditions that rarely, if ever, exist outside the lab. One involves the fabric, and the second involves molten metal created by the arc. PROBLEM #1 — NEW VERSUS USED GARMENTS The lab test that generates ignition thresholds uses new fabric (the ASTM 1958 ignition standard), not used garments. In the real world, garments age in use and three things typically happen, each of which reduce the energy necessary to ignite: • 100 percent cotton garments lose mass through abrasion (and remember, weight is closely related to ignition threshold). • Cotton garments typically develop thin spots, often at the knees, elbows, collar and above pockets. These areas can ignite at much lower energies than the same fabric when new and support flame-spread to the rest of the garment. • Flammable contaminants whether they be hydrocarbons from work or fabric softener, bug spray, etc. from home, will all reduce the amount of energy necessary to ignite the fabric. It is strongly recommended to thoroughly clean an FR garment that becomes soiled with a flammable contaminant and retire garments that are worn out. The primary difference between non-FR 100 percent cotton clothing versus FR clothing is that if ignition occurs, FR garments will self-extinguish after the source of ignition is removed, while non-FR 100 percent cotton will continue to burn long after the fuel that initially helped cause ignition has been consumed. This continued burning can be the difference between life and death. PROBLEM #2 — LABORATORY VERSUS REAL WORLD The lab arc uses a thin wire to initiate the arc and electrodes with a 12-inch gap—this creates a very "clean" arc with much less molten metal than most utility or industrial equipment. Actual equipment arcs usually involve a large volume of molten metal and the arc can "wander." Molten copper spraying out at 1900 degrees Fahrenheit can easily cause ignition of non-FR cotton regardless of weight. Many mannequins exposed to arc flash using actual equipment at the KEMA lab in Chalfont, Pa. (while dressed in FRC) were covered with molten copper to well below the knees, even though the faulted disconnect or splice was at chest level. Another rationalization used to support the wearing of non-FR cotton pants is that arcs are expected to occur at torso height. The lab uses a Faraday cage to contain the arc, but of course there's no such restrictor in real gear. While the equipment that create arcs, may be at chest level, the arc can travel out in any direction, including down. There's plenty of high-speed video analysis of arcs in both low- and high-voltage equipment that shows this phenomenon. Some hot stick video even shows that several cycles "stay home," while the last cycle rockets out eight to 10 feet, directly at the mannequin. Another rationalization is that working in a bucket obviates the need for FR pants because, the theory goes, the bucket will protect the legs. Again, video analysis of arcs and lab tests paint a very different picture. Most people would agree that when an electrical worker is in a bucket, the work is almost always above the top lip, usually by several feet. We've just discussed how arcs in real life wander (KEMA has frightening video of an arc shooting directly into a bucket). The bucket then becomes a confined space, and in effect intensifies the arc. The non-FR pants instantly ignite and burn so fiercely that the instrumented mannequin required extensive repairs. Test witness Ed Smith, shop steward for the UWUA 1-2, says, "There's a dangerous but common misperception that heavy cotton won't burn. In fact, it ignited easily, burned vigorously, and consumed the clothing quickly. If you work around electricity, you need to be in FR clothing." With all of the potential problems associated with non-FR 100 percent cotton, you're probably asking, "Why are electrical workers allowed to wear non-FR cotton?" In the past, utility companies had valid concerns about the options available in FR clothing. The fabrics were stiff and very uncomfortable, and the garment styles were nowhere near the styles linemen were used to wearing. In addition, the requirements of the primary standard for the electric utility industry, OSHA 1910.269, were unclear when it came to clothing. Today, you can find market-proven, engineered FR fabrics made from blends of natural and synthetic fibers, such as INDURA(r) Ultra Soft(r), that offer the soft, breathable comfort of cotton with enhanced durability, as well as many styles including denim, high ATPVs and flame resistance that is guaranteed for the life of the garment. The impending revision to the 1910.269 standard will clarify the clothing issue and close the loophole that led some utility companies to justify policies that allow the use of non-FR 100 percent cotton. Incident Prevention Magazine Article July/August 2005 by: Scott M. Margolin, field technical manager for Westex Inc. He can be contacted at westexinc.com

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Key factors in Selecting FR Clothing

 

Question - When in the initial phases of coming into compliance with NFPA 70E and starting to evaluate different FR garments, why wouldn’t you just go with the least expensive garment that meets the standard?

 

Answer – While garments can look very similar on the surface, they often contain different characteristics.  This is especially true in flame-resistant garments, where key elements like fabric brand used and construction techniques can make a real impact on both performance and wear life over time.   Additionally, your company may have specific “business-to-business” needs in order to service your program, from credit, to specific alterations required, to the need for non-stock sizes or ordering online.

 

When evaluating flame-resistant clothing, it is about finding products that offer the best balance of protection, comfort and value.

 

Protection Considerations: The safety of your employees is the most important factor, so the number one consideration is protection.

 

1. Flame resistant durability. You need to make sure the fabric provides the protection level you require, and also have confidence that the FR protection will last over the wear life of the garment.  Many garments today last years, which can mean 75 launderings or more.

2. FR manufacturer experience. You want to have the confidence that the next garment you buy will possess the same quality and FR performance as the last one you bought. The manufacturer should have ongoing quality control processes to ensure the integrity of the garment, and be able to track every garment back to the original fabric roll.

3. Withstanding real world conditions. The fabric and garments should meet the minimum standard requirements as well as be constructed for durability and designed to withstand real world conditions.   “Real world” conditions takes into consideration performance after many wash & wear cycles as well as differing wash formulas. For example, industrial laundry wash formulas that may be harsher than those cited in standards.

 

Comfort Considerations: After protection, comfort is probably the second most important variable. If your employees dislike their FR uniform, they may not wear it consistently, or properly. 

 

1. Wear tests.  In recent years, there have been many new flame resistant fabrics entering the market, so you will have a choice.  On the subject of comfort, one way to really know what works best in your work environment is to have your employees conduct a wear test among various garments. Working with a garment manufacturer that supports wear tests can be important.

2. Sizing & cut. Another key factor in comfort is how the garments are sized and how they’re cut. Having a more generous fit and having features like pleats and gussets help with ease of movement and can feel better on the job.   Also, does that manufacturer offer a “short” or “long” that has been proportionally cut to fit that stature?

3. Non-stock sizes.  You’ll also likely need garments to fit every employee at your location regardless of size.  Be sure the manufacturer you select provides a broad range of sizes and can provide timely turn around on non-standard sizes.

 

Value Considerations:  Because flame resistant garments are more expensive than regular work wear, value is an important consideration.  For FR, value is more than just the upfront cost of a garment. If you have to replace it early because of excess shrinkage, or the seams fail, your cost per wear on that cheaper garment might really be higher than a higher quality garment.

 

1. Garment shrinkage. Certain types of flame resistant fabrics tend to have lower shrinkage.  In particular, cotton based FR fabrics can vary in terms of shrinkage over time, and with 6% shrinkage you have moved down a complete size and will not fit that employee properly any longer.

2. Durable construction. Garments that are constructed for durability will also last longer. Construction features like reinforced snaps, multiple bar tacks in high stress areas, reinforced pockets, double and triple feld seams, and high stitch counts are a few techniques that can extend the life of a garment.

 

There is a saying that you “get what you pay for” and flame-resistant garments are no exception.   The least expensive garment may not necessarily be the best choice in terms of value or providing protection over time.  It is important to look for experienced suppliers who have the resources to stand behind their product and provide the ongoing consultation and services that are often required to help you manage a corporate flame resistant program over time.

Mark Saner
Mark is technical director for Workrite Uniform Co. With over 30 years experience in the fire and safety industry, he is a member of ASTM serving on committees F18 “Electrical Protective Equipment” and F23 “Protective Clothing” and a member of NFPA committees.  Mark can be reached at msaner@workrite.com or (805) 483-0175 x236.

↑ RETURN TO TOP ↑   High-Visibility Apparel

ISHN Article March, 2010

High-Visibility Apparel – Get the right garment for you.

You may be aware the November 24, 2008 Code of Federal Regulations 23 CFR – Part 634 requires “All workers within the right-of-way of a Federal-aid highway who are exposed to traffic (vehicles using the highway for purposes of travel) or to construction equipment within the work area shall wear high-visibility (Hi-Vis) safety apparel”. This can include many groups of workers for example: construction workers, survey crews, utility workers, EMS responders to accidents and even law enforcement for accidents and directing traffic. So there are many types of workers that need to comply with ANSI/ISEA 107 and wear the proper Hi-Vis apparel. In addition on October 20, 2009 OSHA issued a letter of interpretation stating that all highway and road construction workers must wear high-visibility apparel regardless of whether the Manual on Uniform Traffic Control Devices (MUTCD) requires them to wear it or not. So OSHA’s stance is simple, Hi-Vis apparel is mandatory for workers in these roadway danger zones.

The 2004 edition of ANSI/ISEA 107 specifies all the performance requirements for high-visibility safety apparel. These requirements include the physical properties of the background fabric and reflective bands, as well as various configuration requirements for the garments and reflective tape. It also specifies the minimum amounts, approved colors and placement of these materials. The purpose of this standard is to provide conspicuity to the wearer in hazardous situations under any light condition by day and under illumination by vehicle headlights at night. It’s all about making workers safe in roadway conditions where they may be otherwise hard to see.

Workers near roadways not only need to wear Hi-Vis apparel, but they also need to wear the proper class as laid out in the standard. There are four classes of Hi-Vis apparel. The standard describes the performance requirements for each class and provides some suggested guidelines for when to use the various classes. Ultimately it is the user’s responsibility to determine which class of Hi-Vis apparel is right for their situation.

Class 1: This is the lowest class and requires the least amount of background material and reflective tape. It also does not require a moving body part (i.e. arms or legs) to be part of the garment. The typical application is when the worker is well separated from the traffic and the vehicle or equipment speeds are less than 25 mph. This application could include parking lot and warehouse environments. The Class 1 garment is a typically a vest.

Class 2: This class is a medium level of visibility and requires more material and tape. It still does not require a moving body part to be included. The typical application for Class 2 is for workers on or near a roadway, traffic speeds over 25 mph, and a higher level of traffic and congestion. This application could include construction crews, utility and survey workers and traffic police. The Class 2 garment can be a vest, shirt or jacket.

Class 3: This class is the highest level of visibility and requires the most material and tape. The requirements also include having material and reflective tape on arms and/or legs. A sleeveless garment or vest alone cannot be considered a Class 3. The typical application for this class is for workers in higher traffic speeds (greater than 55 mph) and reduced sight distances (Workers must be visible at a minimum distance of 1280 feet). Class 3 would likely include highway workers, utility and survey crews and emergency response personnel.

Class E: This class is just for trousers and shorts and is not a required Class. However, Class E trousers or shorts can be worn with a Class 2 garment and the ensemble will be considered Class 3. Class E cannot be worn alone and meet any of the required classes.

There are other issues to think about when someone like a utility worker wears a Hi-Vis garment while doing work on power lines near a roadway. In this situation the Hi-Vis garment should also be flame-resistant (FR) because not only are the workers exposed to the hazard of traffic, but they are also exposed to a potential arc flash hazard. And in the case of arc flash protection the outermost garment should always be FR. So, when Hi-Vis and arc flash protection are required the outermost garment would be the Hi-Vis. In the case of FR Hi-Vis for utility workers, the garment should have the proper arc rating (cal/cm²), and meet the requirements the National Electrical Safety Code. You also need to make sure that not only is the garment itself FR but the reflective tape should be FR as well. Because of the large amount of reflective tape required, if the tape is not FR it could ignite and continue to burn when exposed to an arc flash. So for utility workers and others that need arc flash protection as well as Hi-Vis, just meeting ANSI 107 is not enough to provide the needed protection.

There is a lot more to being Hi-Vis than just looking Hi-Vis. Choose the Hi-Vis Class of garment that best fits your situation and check to see if it meets the standard by being labeled as an ANSI 107-2004 garment. And for Hi-Vis FR, look for the ANSI 107-2004 on the label, look for the arc rating and check that the reflective tape is also FR. There are a lot of choices in the market for Hi-Vis work wear that are not flame resistant. However, Hi-Vis FR is increasingly becoming available, including a full line from Workrite. Whomever you purchase from, be sure your needs comply with both OSHA and FHA requirements.
 

Mark Saner
Mark is technical director for Workrite Uniform Co. With over 30 years experience in the fire and safety industry, he is a member of ASTM serving on committees F18 “Electrical Protective Equipment” and F23 “Protective Clothing” and a member of NFPA committees.  Mark can be reached at msaner@workrite.com or (805) 483-0175 x236.

© Workrite Uniform Company, Inc.

 

↑ RETURN TO TOP ↑   FR basics

FR clothing is designed to protect workers from arc flash and flash fire, two hazards that can cause serious injury or death. In an arc flash, the amount of energy released is “quite significant,” with temperatures reaching between 10,000 and 20,000 degrees Fahrenheit, explains Dan Bowen, technical marketing specialist for DuPont Personal Protection.
“Even though the duration of an arc flash is usually fairly short, on the order of less than 1 second, the amount of intense heat will cause anything combustible to burst into flames almost immediately,” Bowen says. “There's been a tremendous amount of people injured and killed by arc flash events that suffer badly because the clothing they were wearing caught on fire.”
Bowen explains that workers' clothing plays a big role in the extent of their injuries in the event of an arc flash, especially if they are wearing a synthetic blend such as polypropylene or nylon blends.
“The challenge with those fabrics is not only will they ignite, but they'll burn vigorously because they're plastic,” Bowen says. “They are highly flammable. They melt, they burn, they drip. They make a bad matter much worse.”

When FR clothing is exposed to a heat source and that heat source is then removed, the garment will not continue to burn, Bowen explains. “That's not to say these things are fire proof. It's not like wearing cement or steel — they will undergo a physical change — but as soon as the heat source is gone, that fabric won't burn. It's designed to provide protection for the worker from that burn injury.”

Scott Margolin, international technical director at Westex Inc. adds that if a worker's street clothes ignite, the fire and subsequent burn injuries will spread to areas of the body where the arc itself never touched.

“As silly as this sounds, you're literally better off naked because the body burn injury you would suffer is going to be limited to the areas of the body where the arc hits. [If] your garments ignite, that fire is going to spread very rapidly,” he says. “As soon as the shirt ignites, you're shifting from survivable or no injury with FR clothing, to potentially or probably fatal injury [without FR clothing] within seconds.”
FR clothing also provides protection through insulation, shielding the body from the heat of the event.
“The analogy that I like to make is you wouldn't wear a windbreaker out into a blizzard, would you?” Margolin says. “If you know it's 55 degrees out, you can put a windbreaker on and you're going to okay. If it's -55 degrees out, you're not going to wear that same lightweight jacket — you're dressing appropriately to that hazard, in this case cold.”

MISCONCEPTIONS

As with any PPE, workers and safety professionals must have a full understanding of the equipment to properly and safely use it. Misconceptions about FR clothing can be dangerous. For example, Margolin cites the erroneous belief that cotton is an upgrade from synthetic blend materials. While cotton doesn't melt, wearing cotton garments in the event of arc flash or a flash fire could be deadly.

“Cotton ignites just as readily as poly cotton, and it burns hotter, meaning it will do more damage to your skin more quickly,” Margolin says. “It's harder to extinguish and it's typically heavier, which means more fuel for a longer fire. Cotton is not an upgrade. It does ignite, and it's equally hazardous.”

Another troubling misconception is that workers need an FR shirt or jacket but not FR pants. Not wearing full protection, Margolin warns, is a dangerous move.

“You wouldn't do that any more than you would wear half a hard hat or one lens of a safety glass, or just the right glove for shock protection but not the left one,” he says. “A shirt-only program is not a program at all. You're not compliant, [and] you're not going to save yourself the fatalities or medical costs.

Finally, Margolin stresses that not all FR is the same.

“Just because something has an arc rating doesn't mean it's a long-term, viable product, so we urge people to look for market-proven products,” he says. “There is no excuse in our business today to wear a garment where you have to count the launderings. There are plenty of fabrics out there that are flame resistant for the life of the garment. I would urge people to look for market-proven products.”

Bowen adds that when it comes to FR clothing and protection from flash fire, some safety professionals are content with doing only the bare minimum to remain compliant.

“With flash fire, everyone looks at the lowest possible denominator, but every place else they're willing to step up and look at the hazard,” Bowen says. “Nobody skimps on respirators. Employers will purchase and mandate that their employees use the correct level of respiratory protection, but they don't do the same thing with flash fire.”

COMFORT

Another commonly misunderstand aspect of FR clothing is how comfortable it can be.

“There's a misconception that flame-resistant clothing is heavier, stiffer, scratchier or uglier than street clothing. That's one of the reasons people don't get it,” Margolin says. “We have been engineering for years trying to get lighter and lighter and softer and softer and more and more street looking. And with at least a few brands, we have gotten there.”

Lanny Floyd, principal consultant for electrical safety and technology at DuPont, agrees that FR garments today are being developed for higher performance and lower weight. “Over the last 10 years, there have been significant advances in the comfort and usability” of FR fabrics, he explains. Additionally, the face shields and hoods used in arc flash protection also have been improved.

To find the FR fabric and clothing that will be most comfortable for workers, Bowen suggests that safety professionals conduct a wear trial. Identify several different fabric types and garment manufacturers and obtain sample garments. Let workers wear these garments in real-life work situations so they can determine what feels best. “Look at the job that needs to be performed, look at the features you want on the garment, identify a few options, put it on people and let them wear it for a couple of months,” Bowen says.

LAST LINE OF DEFENSE

Floyd also stresses that workers must know how to properly wear and use FR clothing. That means securing all fasteners, ensuring all body parts are protected, never rolling up sleeves and repairing any damage immediately and with the appropriate materials, such as FR thread.

Users also must follow the garment manufacturer's instruction on care and cleaning. Don't allow contaminated materials, solvent or grease that could ignite and degrade the performance of the protective clothing come into contact with the garments.

Finally, Floyd explains that one of the big areas of opportunities in the FR world is education on when and how to use these garments properly.
“That's one of the big gaps I think we have today,” Floyd considers. “We have great products and great standards to improve safety for workers, but making sure people understand how to use it properly is always a challenge. Ongoing education is very important.”

Knowing the basics can do nothing but help improve the safety of workers. Following a few basic rules, research and try out the garments before you buy, and sticking with proven suppliers can go a long way in making your FR program a good and safe one.

Exerpts from January 2010 EHS Today magazine article by Laura Walter
© Workrite Uniform Company, Inc.
 

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Combustible Dust - A Hot Topic

On Feb. 7, 2008, a combustible dust explosion ripped through the Imperial Sugar Co. refinery in Port Wentworth, Ga., killing 14 employees and injuring dozens. The incident triggered $8 million in proposed OSHA fines, a Senate hearing, a renewed call for an OSHA standard and widespread concerns about combustible dust hazards. It also prompted Imperial Sugar to make some changes in its facilities and procedures — including outfitting all workers in fire-resistant (FR) clothing.

“Post-event, we have required all employees and visitors to the manufacturing areas to wear fire-resistant clothing. It's a blanket requirement and one that is we believe quite conservative,” says Ron Allen, who joined Imperial Sugar as senior director of environmental, health, safety and quality in March 2009. “It's probably unusual for a manufacturer of dry product to require fire-resistant clothing plant-wide for all employees.”

Scott Margolin, international technical director at Westex Inc., acknowledges that in the event of a combustible dust incident, some fatalities may be unavoidable because of explosions, entrapment or sustained fire. But “vastly more people” often are involved in the flash fire portion of the event, he says.

“If it doesn't ignite your clothes, you're probably going to live. And if it does, you're probably not,” Margolin says. “FR clothing can make a huge contribution to worker safety in that area.”


A COMBUSTIBLE DUST STANDARD

On Oct. 21, 2009, OSHA published an Advance Notice of Proposed Rulemaking as an initial step in developing a standard to address the hazards of combustible dust. Ron Allen represented Imperial Sugar at OSHA's Dec. 14, 2009, stakeholder meetings on this issue.

“We are strong advocates for an OSHA standard,” he says. “I came away [from the stakeholder meeting] with an appreciation that there are many different opinions that will influence the final standard.”

According to Allen, OSHA representatives “seemed to sincerely have an open mind and are listening to the various stakeholders as they attempt to put together this new standard.” He adds that he'd like to see a combustible dust standard with specification language as opposed to performance language.

“Performance standards are very attractive on the surface, but could be much more difficult to administer than a specification standard,” he points out. “We think that specification language actually serves as an education. It helps employers, particularly small employers, who may not have a great deal of technical resource to understand what they must do to protect their employees from combustible dust fires and explosions.”

“Combustible dust is a hot-button issue with OSHA and FR,” says Margolin, who also attended the December 2009 OSHA stakeholder meetings on the development of a combustible dust standard. “The first line of defense of any of these things is to engineer the hazard out or down,” he explains.

“Flame-resistant clothing, while it is admittedly the last line of defense after behavioral and engineering safety have been addressed, cannot and must not be overlooked. Just because a car has crumple zones and impact-absorbing bumpers and air bags does not mean you can forget to put on your seat belt,” Margolin says. “Same kind of logic.”


A COST-EFFECTIVE SOLUTION

“OSHA has clearly embarked on a path that's going to result in a rule on combustible dust,” says Margolin. The big questions to me seems to be about scope, and what language [of existing NFPA standards], if any, will make it in.”
According to Margolin, the meetings focused on existing NFPA consensus standards, the potential scope of a standard, economic impact and hazard mitigation. FR clothing also entered the discussion, particularly in terms of economic impact. Margolin is quick to point out just how cost-efficient FR clothing can be.

“Body burn is the second most expensive hospitalization in the U.S.,” he says. “Putting everybody who remotely needs FR clothing in it for the rest of their careers costs vastly less than the first year of medical expenses alone for the burn injuries that are already happening, much less the ongoing medical costs, insurance, workers compensation, counseling, fines and lawsuits.”

Overall, Margolin was encouraged by what he calls an obvious intent to develop and implement a standard for combustible dust. “It's not a matter of if but when they will put out a rule on combustible dust,” he says.

The types of dust identified by OSHA as being likely to cause dust deflagrations, other fires, or explosions include but are not limited to:

• Metal dust such as aluminum and magnesium.

• Wood dust

• Coal and other carbon dusts

• Plastic dust and additives

• Biosolids

• Other organic dust such as sugar, flour, paper, soap, and dried blood.

• Certain textile materials.

The industries that handle these combustible dusts include, but are not limited to:

• Agriculture

• Food Products

• Chemicals

• Textiles

• Forest and furniture products

• Metal processing

• Tire and rubber manufacturing plants

• Paper products

• Pharmaceuticals

• Wastewater treatment

• Recycling operations (metal, paper, and plastic.)

• Coal dust in coal handling and processing facilities.

If your industry falls into one of these categories you should probably start a process to determine if you have a potential problem waiting to happen and figure out a course of action. Eventually OSHA will make a rule and being ahead of the curve will put you in a good position.

Excerpts from January 2010 EHS Today magazine article by Laura Walter
© Workrite Uniform Company, Inc.

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Common Electric Arc Flash - PPE Mistakes   After 15 years of arc flash testing, investigations and replications with electric arcs, a few lessons have emerged as critical in Personal Protection Equipment (PPE) programs: 1. PPE has to be worn? Whether it's because of a lack of training, a policy saying "wear it when it's needed," or if the right garment wasn't picked for the job, PPE is no good if it isn't worn. Most accidents happen when the worker believes they need no protection. If the employer buys the least expensive garments, they will have poor compliance to their policy. Another reason why PPE isn't worn is that the company believes more is better and provides heavy, uncomfortable PPE. If it is worn all the time, less can be best. The greatest difference in clothing for the arc flash is the difference between non-FR and FR. To be concerned about the difference between a 100 cal/cm² suit and a 40 cal/cm² suit is to miss the point. Many companies will provide 100 cal/cm² suits, which are not worn. It is best to have a worker in an 8 cal/cm² shirt and an arc rated jean than in 100% cotton because arc rated clothing will not ignite. If workers are working in arc flash hoods more than 20 minutes per day, consider a lightweight suit, which is at least 40 cal/cm². Some of the 40 cal/cm² suits are one half the weight of others. Adding venting to a hood may add $200 to the cost of the hood but it can make a huge difference in worker comfort. Field trial the options to see real world performance. Considering comfort increases compliance. 2. Flame Resistant in the label doesn't mean anything. FR Acrylic, nylon and polyester are not really flame resistant for practical purposes. These materials should use another name because "flame resistant" by definition gives the user the wrong impression. They may be fine for a worker who has little or no flame exposure but they are dangerous in electric arc and flash fire conditions where these products melt into the skin. Products you choose should meet the right standards. Here are the standards to specify: Clothing -- ASTM F1506 Rainwear -- ASTM F1891 Hoods and Face Shields -- ASTM F2178 Fall Protection Exposed to Electric Arc -- ASTM F887 Gloves -- ASTM D120 Flash Fire Clothing -- NFPA 2112, CGSB 155.20 3. Using FR Rainwear rather than Arc-Rated Rainwear. Make sure you have the right rainwear. Only rainwear that meets ASTM F1891, F2733, or NFPA 2112 will not melt in arc flash or flash fire conditions. Arc-rated rainwear is usually built with inherent or inherent blends. Nylon or polyester, even if labeled "FR" are not acceptable in rainwear exposed to arc flash or flash fire. 4. Using non-FR winter wear over FR and thinking you are protected. An FR shirt under a flammable jacket will not protect. Winter wear that does not meet ASTM F1506 is dangerous in an arc flash. In two accidents I have investigated, a non-FR winter jacket burned workers under FR clothing over 50% of their body. Many winter jackets and liners are now available which keep workers warm and protected. 5. No training on undergarments. In order the meet the NFPA 70E standard, workers are required to wear non-melting natural fiber undergarments or arc rated underwear. Flame resistant bras and other undergarments are available. Avoid any wickable material which can melt. These materials should not be worn as underwear in arc flash or flash fire exposures. Plain cotton, wool and silk are all good options for undergarments or arc rated t-shirts are acceptable. Simplifying an arc flash PPE program by using daily wear with 8 cal/cm² protection and adding an arc flash rain suit, or an additional coverall or a lightweight flash suit with a flash suit hood makes a well rounded program easier to live with and work in. Details on this type of program can be seen in Annex H of NFPA 70E. Article by Hugh Hoagland - About the Author: Hugh Hoagland's companies do arc flash training, arc flash testing and arc flash studies. http://www.e-hazard.com © Workrite Uniform Company, Inc.   ↑ RETURN TO TOP ↑   Beating the Heat   Heat stress is a very dangerous condition that can affect many workers. It is particularly prevalent during physical activity in hot and humid working conditions. And during the summer months this can apply to many workers. It is not only dangerous to the worker’s health but it also decreases worker productivity and the quality of their work. Heat stress can manifest itself in many ways including heat rashes, heat cramps, heat exhaustion and ultimately heat stroke. This illustration shows the temperature and humidity levels where heat stress is possible to occur and where it becomes dangerous. At temperatures between 85°F and 95°F with humidity levels from 30% to 60% heat stress is possible. Above 95°F and humidity above 60% workers are in danger. HOW THE BODYS COOLS ITSELF The body continually generates heat that must be released in order to maintain the proper core temperature of 98.6°F. The body’s response to the increase of heat is to sweat. Moisture from the cells and blood rises to the skin surface through sweat glands when the core temperature rises. As the sweat evaporates, it draws the energy needed to vaporize the moisture from the remaining sweat on the skin. This action leaves cooler moisture on the skin which helps reduce the overall core temperature. This is called evaporative cooling. There are four basic mechanisms to cool the body. Radiation – heat from the skin is absorbed by the surrounding cooler air (normally 64% of the body’s heat release) Conduction – heat pulled away by direct contact with a cooler object like water (normally 2%) Convection – moving air (breeze, fan) can encourage evaporation and heat loss (normally 10%) Evaporation – moisture on the skin’s surface (sweat) evaporates leaving cooler moisture and skin – evaporative cooling (normally 23%) CONTRIBUTING FACTORS There are many factors that affect the level and the speed at which heat stress can occur including: Age – our ability to produce sweat decreases with age Gender – men begin sweating at a lower temperature than woman BMI – more fat insulates the core which increases sweat production Hydration – not consuming enough water causing dehydration Activity level – the more active the more heat generated and increased sweat production TYPICAL WARNING SIGNS There are numerous warning sign that occur as heat stress begins to occur. Knowing the warning signs could allow a worker to take the appropriate steps to get the situation under control. Some of the warning signs are: Headache, lightheadedness, dizziness, unusual fatigue, irritability, confusion, nausea/vomiting, cramping and diarrhea. These signs manifest due to the body redirecting blood from internal organs and muscles to the skin in an attempt to shed the heat. Plus the sweating action means a loss of fluids and possible dehydration. TIPS TO REDUCE EFFECT There are a number of actions that can be taken to help reduce the affect of heat stress including: Rest – take regular rest breaks Hydration – drink lots of water Shade – take advantage of a shady spot when possible Type of garment/fabric – wear light weight and light colored garments/fabrics that don’t trap in the heat and promote evaporative cooling Limit alcohol consumption The two most effective ways of reducing heat stress are taking regular rest breaks and drinking plenty of water, particularly above 95°F and at high humidity levels. When it comes to the type of garment and fabric, their function in minimizing heat stress is one of allowing the heat to radiate off the body by not trapping in the heat (weight & weave) and also by helping move sweat off the skin and onto the surface of the fabric (wicking) where it can evaporate. Although the attire worn can play some role in reducing heat stress, research and information we received from key suppliers (Westex, DuPont) indicate that single layer garments, in general, play a relatively minor or inconsequential role in causing or reducing heat stress; especially as compared to those more important practices of proper hydration and rest breaks. The information shows that commonly used single layer FR fabrics show little difference in their ability to provide the wearer with more or less heat stress relief in severe heat conditions. Weight – the weight of the fabric is a factor in that the sheer mass of the fabric serves as insulation and can restrict heat from releasing away from the body. This is why a heavier fabric typically keeps you warmer in cold weather and lighter weight is typically cooler in hot weather. Weave – the weave plays a role by allowing air flow (air permeability) to assist in cooling (convection) by picking up heat as well as helping to evaporate moisture (evaporation). It can also work in reverse if the air is hotter than the skin. In this case heat is transferred from the air to the skin. Wickability – the fabric’s ability to absorb moisture from the skin and transfer it to the surface allows for evaporation and for evaporative cooling to take place. HOW DO WICKING FABRICS WORK? Wicking fabrics are typically a blend of hydrophobic and hydrophilic fibers. Hydrophobic fibers absorb very little moisture while hydrophilic fibers readily absorb moisture. Hydrophobic fibers are typically synthetic fibers like polyester, nylon, modacrylic and aramids. Hydrophilic fibers are typically made from natural substances based on cotton, wool, silk, and rayon. When sweat forms on the skin the hydrophilic fibers absorb the moisture from the skin which draws heat away. Through capillary action the moisture is spread across the fabric. The moisture on the surface of the hydrophobic fibers can then evaporate quickly, which keeps the evaporative cooling process going. Fabrics with only hydrophobic fibers can and often do have a wicking finished applied to assist with moving the moisture off the skin. The finish does typically work well when new but may have limitations in the amount of moisture it can move because the fibers themselves do not absorb any moisture. Also, the capability of the finish does diminish over time as the garments are laundered. The number of launderings it will withstand is dependant on the durability of the finish and the type of laundering. For evaporative cooling, a balanced blend of hydrophilic and hydrophobic fibers may be more effective. Too little hydrophilic fiber means the amount and rate of absorption is slower, reducing the amount of evaporation and heat removal. Too much hydrophilic fiber and the fabric may get wetter and tend to stay wet, which can reduce the effects of evaporative cooling. A good balance can help pull the moisture away and distribute it evenly across the surface for cooling. THE BOTTOM LINE To minimize the potential for heat related problems, particularly in hot, humid working conditions – take regular rest breaks, drink plenty of water, wear the right clothes for the situation and know the warning signs so you can take the appropriate actions, before the situation gets dangerous. Mark Saner – Technical Manager Workrite Uniform Company © Workrite Uniform Company, Inc. ↑ RETURN TO TOP ↑   Arc Ratings and Hazard/Risk Categories   The Arc Rating and Hazard/Risk Category (HRC) of an FR garment are two terms that are used a lot and for some they can be misunderstood. Every FR garment being used to protect against an electric arc flash should have an arc rating assigned to it. Both NFPA 70E and the National Electrical Safety Code (NESC) require the use of arc rated materials in the FR clothing used by the workers covered under these safety standards.   What is an Arc Rating? The arc rating of a material is defined by ASTM as the “value attributed to materials that describe their performance to exposure to an electrical arc discharge”. The arc rating is expressed in calories per square centimeter (cal/cm²) and is derived from the determined arc thermal performance value (ATPV) or energy of breakopen threshold (EBT). Both are considered the arc rating for the material. An ATPV is the amount of thermal energy, in cal/cm², applied to a material or layers of materials that result in a 50% probability sufficient heat transfer is predicted to cause the onset of a second-degree skin burn injury based on the Stoll skin burn injury model. An EBT on the other hand is the incident energy on a material or layers of materials that result in a 50% probability the material will break open due to the exposure. Both of these arc ratings are determined by performing the ASTM 1959 test method titled “Standard Test Method for Determining the Arc Rating of Materials for Clothing”. The test exposes flat fabric samples to varying intensities of electric arcs. The samples are placed over heat sensors which measure the heat rise during the arc exposures. The results are recorded and analyzed to determine when there is a 50% probability of a second degree burn which is its ATPV. If the material breaks open before the heat rise gets to the ATPV an EBT is assigned in lieu of an ATPV. Either an ATPV or EBT are acceptable arc rating to meet the standards. Typical arc ratings are numbers like 5.1 cal/cm², 8.7cal/cm², and can be as high as 35.8 cal/cm² or higher. An EBT can be a similar number and is more commonly seen as a rating for knits, fleeces or higher rated insulated materials.   What is a Hazard/Risk Category (HRC) HRC is a term used specifically in the NFPA 70E Standard for Electrical Safety in the Workplace. The NFPA 70E Standard suggests two methods of determining the appropriate protective clothing and other personal protective equipment (PPE) for protection against an arc flash. One is based on performing an actual incident energy (cal/cm²) analysis for each specific task, while the other uses the Hazard/Risk Category table found in the standard. If the incident energy analysis is used, the protective clothing and other PPE must be equal to or greater than the incident energy (cal/cm²) established from the analysis. If the table is used, each specific task listed establishes one of five HRC category requirements for the protective clothing and PPE to be worn while performing that task. Each category outlines the minimum arc rating (cal/cm²) for the FR clothing and other PPE required. Here are the basic requirements for the 5 HRC categories.   HRC 0 – FR clothing is not required but the clothing must be non-melting or untreated natural fibers. PPE includes safety glasses or goggles, hearing protection and leather gloves.   HRC 1 – FR clothing with a minimum arc rating of 4 cal/cm² (long sleeve shirt & pants or coverall, and arc rated face shield or hood). PPE includes hard hat, safety glasses or goggles, hearing protection, leather gloves and leather work shoes optional.   HRC 2 – FR clothing with a minimum arc rating of 8 cal/cm² (long sleeve shirt & pants or coverall, and arc rated face shield or hood). PPE includes hard hat, safety glasses or goggles, hearing protection, leather gloves and leather work shoes optional.   HRC 3 – FR clothing with a minimum arc rating of 25 cal/cm²  (either single layer shirt and pant, coverall or a multilayer flash suit system and arc rated flash suit hood). PPE includes hard hat, FR hard hat liner, safety glasses or goggles, hearing protection, arc rated gloves and leather work shoes.   HRC 4 – FR clothing with a minimum arc rating of 40 cal/cm² (either single layer shirt and pant, coverall or multilayer flash suit system and arc rated flash suit hood). PPE includes hard hat, safety glasses or goggles, hearing protection, leather gloves and leather work shoes.   What is the NESC ARC Rating System The NESC has a slightly different arc rating system. It requires a hazard risk assessment to establish the exposure potential of an arc flash for the various work practices. If the hazard has an exposure potential of 2 cal/cm² or greater then arc rated clothing must be worn. Like NFPA 70E there is an option to wear protective clothing with an arc rating equal to or greater than the exposure potential established, or follow one of the simplified tables. In the NESC tables assign a 4, 8 or 12 cal/cm² clothing system to the various work functions based on voltage, fault current and clearing times. However, it does have a couple of exceptions. The first is to allow for lower rated garments if the exposure is below 1000 volts. In this case you simply wear a 4 cal/cm² clothing system. The second is if the designated clothing system can create a greater risk in which case you can move to the next lower rating.   Summary Whether you look for an arc rating or an HRC the key is to provide protective clothing and other PPE that is rated to protect at or above the potential arc flash exposure of the workers. Performing a proper hazard assessment, researching the standard that applies to your situation, and purchasing the appropriate protective clothing and PPE will help keep workers protected.                  Mark Saner – Technical Manager Workrite Uniform Company © Workrite Uniform Company, Inc. ↑ RETURN TO TOP ↑