TEXTILES.ORG
Testing is a complex and critical part of the manufacturing process for protective and occupational gear.
It may be impossible to guarantee personal protective equipment (PPE) in extreme circumstances, but today’s testing standards can offer proven performance for PPE, occupational gear and equipment, and the fabrics they incorporate. Following an industry-standard testing process is critical in mitigating safety and well-being concerns for this market segment.
The fabric provider
Prestige Impex Inc., Cumming, Ga., supplies woven industrial textiles (primarily from cotton fibers) to manufacturers in the safety products, promotional, home furnishing, camping and hunting, filtration and other industries. Prestige also does textile conversions and supplies dyed and finished fabrics, says Steve Qmar, director of sales.
The company specializes in supplying sturdy, heavyweight cotton canvas fabrics, much of which goes into making safety products. Included among these are canvas tool buckets, designed to be extremely abrasion- and cut-resistant; and safety harness bags, multipurpose bags worn like a belt and used to carry tools and items like goggles, vests and flashlights.
“Our customers have to ensure their gear is top-notch,” says Qmar. “For example, the worker may be carrying heavy tools in these canvas bags. If our fabric isn’t up to the mark, chances are high that the bag will rupture and bust open—both unsafe and unproductive.”
Depending on end-user requirements, Prestige’s woven fabrics are tested for weight, thread count, thickness, tensile and tear strengths, air permeability and more. Only fabrics passing ASTM (American Society for Testing and Materials) and AATCC (American Association of Textile Chemists and Colorists) standards are sent to manufacturers.
Textile testing provides the foundation for product performance, Qmar says. “By laying out the basic guidelines and setting up the tolerance limits, it’s fairly easy to predict how a product will perform under certain conditions. This enables manufacturers to write product safety sheets and to know what they should, or shouldn’t do, with the supplied products.”
The fabric finisher
Located in Hickory, N.C., TSG Finishing adds a variety of performance characteristics to different textiles products, says Bud Styles, director of operations/sales. The finishes are applied using mechanical or chemical treatments.
“Our two primary areas are the Military (uniforms) and medical (drapes and gowns),” Styles says. “We do treatments for other specialty applications such as sportswear, workwear, evaporative management, odor control and water repellency. The finishes are primarily applied to synthetic blends but also to a good bit of wool and cotton.”
The company’s top performance categories are water and stain repellency with breathability, “a requirement of most industries and crosses over many markets,” Styles says. But TSG also applies finishes and tests for seam slip/tear resistance, shrink resistance, flame retardancy, abrasion and pilling resistance, antimicrobial and odor control, barrier properties and static dissipation. The company does internal testing focusing on quality control, forwarding the material to an outside lab if needed for certification purposes or market requirements.
Product innovation and manufacturers’ desire to meet consumer needs (and besting their competitors) is fueling the demand for performance testing, says Styles.
“Our customers are focused on their markets and are listening to market demands for new products,” he says. “If you can differentiate yourself from the rest of the market by meeting one more customer need, then success is in front of you.”
The instrument provider
Thermetrics LLC designs and manufactures a broad spectrum of advanced test instruments used for measuring and evaluating the thermal characteristics of textiles, garments and protective clothing, says Dave Heiss, sales and marketing director for the Seattle, Wash.-based company. The company also measures and evaluates the “dynamic environments” of vehicles, aircraft, and home and office interiors.
Thermetrics’ line of thermal manikins, guarded hotplates and flame test systems can be found in certified testing agencies, textile research universities and government labs worldwide. Its equipment is designed to support an extensive range of test methods, including multiple ASTM, National Fire Protection Association (NFPA) and International Organization for Standardization (ISO) standards.
“One driver of test selection is often the amount of historical test data a company may have,” says Heiss, explaining what leads a company to select certain tests over others. “For existing products, it’s important to periodically correlate present performance with past to make sure there has been no decline in the level of protection a garment provides. If garment materials or construction has changed, it’s even more important to assess the new test data with historical benchmarks.”
Heiss believes manufacturers have “three areas of focus” when it comes to their protective gear and garments: comfort, protection and meeting the required government standards.
“Each leads to a series of tests that help define the performance of a given piece of protective gear,” he says. “A minimalist approach is simply meeting the standards, but today’s customer is looking for more than that. They want to know on a more personal level how a garment is going to perform for them.”
Comfort has become a particular concern. For example, over the past several years, moisture management is playing an increasingly important role in the development of new textiles as well as in garment design and construction methods. As textiles become more “complex and multifunctional,” moisture management will continue to be an important test criterion. But there are many testing options, he adds.
“[These] range from tests of a fabric’s physical properties (tear strength, colorfastness, shrinkage) to inherent performance properties such as moisture and heat resistance,” he says. “Test standards exist for all these characteristics, and while many tests are required due to government safety regulations, others can be highly informative and useful for marketing purposes.
“Therefore, textile testing becomes not just a data point that checkmarks a box; it becomes the supporting framework for a story of interaction between the user and the garment,” Heiss continues. “Companies prepared to tell that story will win in today’s marketplace.”
The testing facilities
Intertek provides Total Quality Assurance (TQA) to industries via a network of more than 1,000 laboratories and offices worldwide, says Jason Allen, technical advisor. Headquartered in London, Intertek’s PPE lab is located in Cortland, N.Y. The lab tests PPE worn by people working in numerous occupations and industries such as medical and construction workers, firefighters and EMS workers, hazmat teams, law enforcement, athletes, bomb technicians and more. Among the items tested are helmets, gowns, fall-protection products, footwear, boots, gloves, hazmat suits, eyewear and protective garments.
“We test 1,000-plus methods ranging from thread tests to full ensemble evaluations,” says Allen. “Some of the tests include cut resistance, abrasion resistance, chemical permeation/penetration, viral resistance, tensile properties and breathability.”
A variety of materials undergo testing and evaluation. These include, for example, nonwovens and thin-film-based and semipermeable laminates, evaluated for chemical and viral resistance; and coated and/or aramid-based materials, for cut and abrasion resistance. “We also see plastics, wovens and all other types of materials used within PPE,” he says.
Certain tests become more in demand than others. For example, says Allen, the aftermath of 9/11 saw an increase in requests for tests primarily focused on cut- and abrasion-resistance used on materials and items destined for rescue and recovery.
“And, as the anti-terrorism efforts increased post-9/11, there were also significant requests for the evaluation of a material’s permeation resistance against chemicals such as warfare agents and toxic industrial chemicals like ammonia, chlorine, dimethyl sulfate, acrolein and acrylonitrile,” he says. “Due to the length of time garments made from these materials are often worn, this testing was also coupled with an evaluation of user comfort using tests such as Total Heat Loss (THL).”
Also, thanks to the Ebola outbreak, the lab conducted viral penetration evaluations on a “significant number of materials and products,” says Allen. OSHA’s changes in focus—for example, the agency has recently placed greater emphasis on fall protection—also accelerate the demand for specific types of tests.
CTT Group is a technology transfer center specializing in the research, development and testing of technical textiles, advanced textile-based materials and geosynthetics. Located in Saint-Hyacinthe, Quebec, Canada, the company offers a range of services, from performance and characterization analysis for testing and certification purposes, through research and development to advanced prototyping for new applications, says Valerio Izquierdo, vice president, Textile Laboratories and Expertise. Like Intertek, CTT conducts performance testing on a myriad of products in the PPE category, with the kinds of evaluations performed dependent on the occupational activity.
“[For example], workers potentially exposed to hydrocarbon flash fire—for instance oil and gas extraction—usually have coveralls or protective gear that are compliant to specifications covering various risks,” says Izquierdo. “An exposure to dry heat is performed on the fabrics to limit the risk of intense shrinkage [and materials melting]. The flame resistance is also required. Materials resistance to a flash fire is [also] measured.”
In addition to the normal evaluations for flammability and shrinkage/melting with exposure to heat, the parameters evaluated for firefighter PPE include resistance to penetration by certain chemicals, such as battery acid, gasoline, aqueous film-forming foam (among others); thermal protection; water penetration; THL; and resistance to penetration from microparticulates.
In addition to ballistic vest requirements, protective apparel for law enforcement may require evaluation to prevent penetration of liquids like gas or battery acid, breathability/moisture management (for comfort), resistance to water penetration or water repellency, says Izquierdo. Items directed to the medical arena, such as surgical drapes and gowns, are evaluated for water penetration, penetration to synthetic blood and viral penetration resistance.
“Even professional hockey players or other athletes such as speed skaters, have specific needs; for example, cut resistance,” he says.
Textile testing allows for the objective performance evaluation of a given material, since the tests are based on standard test methods available through widely recognized and accepted entities, says Izquierdo.
Testing can also save manufacturers money, says Allen. “It can help sort out an end product’s likelihood of success prior to the creation of expensive prototypes.”
Pamela Mills-Senn is a free-lance writer based in Long Beach, Calif.