ArcWear™ MP3 3000 Series Protective Outerwear Technical
Extensive field testing has led to this breakthrough technology. MP3 (Multi-Performance Trilaminate) is a protective all-weather system that is lightweight, waterproof, breathable and windproof. For the first time, you now have a choice to match comfort and safety.
MP3 is ASTM, NFPA 70E and NFPA 2112 certified: Electric Arc (ASTM F1891, NFPA 70E PPE CAT 2), Flash Fire (ASTM F2733, NFPA 2112), Breathability/Comfort (ASTM E96, ASTM F1868), Waterproof (ASTM D3393), Chemical Penetration (ASTM F903) and Cold Weather (ASTM F2732).
The complete MP3 system comprises:
An outer shell of DuPont™ Nomex® IIIA (refer Innovation below).
A moisture barrier of breathable DuPont™ ePTFE composite film on Nomex® E89™. The moisture barrier provides a strong flame resistant substrate for liquid-impermeable films. The moisture barrier helps protect against intrusion of water, chemicals and viral agents. These barriers are lightweight and breathable to help reduce overall heat loss during strenuous activities.
A thermal layer of Nomex® Jersey Knit. The thermal layer provides the majority of the system's thermal protection. Nomex® nonwovens combined with Nomex® fibre and filament face cloths provide durable, flexible and breathable heat-insulating components. Nomex® based thermal layers are among the thinnest, most flexible and breathable available.
The MP3 system is designed to minimise heat stress and maximise thermal protection and comfort.
MP3 means Multi-Performance Trilaminate. It is a breathable Nomex® IIIA outerwear system designed to excel in all weather conditions. DuPont™ created Nomex® IIIA to provide protection against hazards such as flash fires and pool fire. Nomex® IIIA is a blend of 93% Nomex® with 5% Kevlar® and 2% P-140, a proprietary static-dissipative fibre that reduces static generated when fabric-to-fabric and fabric-to-surface rubbing occur. The P-140 fibre works to reduce static, making garments more comfortable to wear. It also reduces the contribution of clothing to the static charge build-up on the body.
The presence of 5% Kevlar reinforces the Nomex® component and inhibits thermal shrinkage, thus reducing the probability of break-open and the subsequent loss of the protective barrier. This innovative fabric helps minimise break-open and expands to form a stable and inert barrier between the thermal hazard and human skin. This gives PPC wearers valuable seconds to escape the potential effects of a thermal hazard.
Durability and Cost Effectiveness
Woven fabrics of Nomex® IIIA consistently exhibit superior abrasion and tear resistance to comparable, or in some cases, even heavier weight constructions of 100 percent Cotton and polyester/Cotton blends - an advantage that translates into longer wear life.
In addition, garments of Nomex® IIIA exhibit good resistance to a broad range of chemicals and are highly resistant to most hydrocarbons and many other organic solvents¹. Resistance to chemicals existing in industrial work areas enhances the durability of the garment, while also enabling the use of organic solvents to clean the garment and remove flammable contaminants without affecting garment wear life.
On average, garments of Nomex® IIIA last three to five times longer than most other standard and protective fabrics, including 100 percent Cotton, polyester/Cotton and FRT Cotton. In fact, industrial launderers estimate that the average life of garments of Nomex® IIIA is five years and that they can be washed and worn at least 125 times, depending on the end-use environment. In contrast, garments of FRT Cotton can be washed and worn on average of only 25 to 40 times.
MP3’s versatility makes it perfect for many applications. With an available Nomex® IIIA fleece lining, extended life cycle and retail appearance, MP3 is more than just raingear. MP3 has been proven successful in replacing other items provided to workers, such as windbreakers, FR hooded zipper sweatshirts, corporate image apparel, FR winter wear, FR fleece and traditional rainwear. MP3 offers a value proposition not available with traditional rainwear products. Its versatility and extended life cycle combined with a 3 year warranty create a value savings of 15% to 35% compared to common rainwear products used today.
Of all the factors that determine physical comfort, the most basic is thermal comfort, or the body's ability to manage heat. The balance between creating and losing body heat helps determine how cool an individual feels. Evaporation and convection are the body's two most important cooling methods and major contributors to comfort. For cooling to occur, heat generated by activity must be lost or dissipated through the skin and clothing.
Convection transfers heat away from the body into the cooler atmosphere when air moves across our skin or through our garment. Air movement, ventilation and wind all increase the amount of heat loss through convection. Evaporation is the body's most efficient method of heat loss. When the air is hotter than we are, it cannot take heat from us through convection, so we perspire. When our perspiration evaporates, heat is taken from our skin and our body temperature is lowered.
Only breathable fabrics can take advantage of these types of heat loss. Fabrics that do not breathe adequately cause perspiration to build up inside the garment, while fabrics which absorb moisture, such as Cotton, quickly become saturated. A garment saturated with moisture clings to the skin creating a damp, uncomfortable feeling.
Breathable Nomex® IIIA rainwear is designed to collect and transfer perspiration out of the garment as well as allowing a measured amount of heat loss. This leaves the worker dry from both the transferred perspiration and the rain.
Extensive testing of Nomex® IIIA garments on THERMO-MAN®² has shown that exposures at a heat flux of 2 cal/cm2 over a range of exposure times result in predicted body burn injuries that increase steadily and gradually with increasing exposure. No sudden, unexpected rise in the rate of heat transfer occurs and burn injury results solely from heat transfer through the fabric. In contrast, although FRT Cotton provides some thermal protection at low exposures, predicted body burn injury increases dramatically as exposure time increases.
Laboratory tests using a life-size mannequin were also conducted to evaluate the performance of various fabrics when exposed to high-energy arcs. This test measures the ability of the fabric to resist ignition and to break-open, that is, maintain a physical barrier between the arc blast and the skin.
A shirt constructed from various fabric weights of Cotton, FRT Cotton and Nomex® IIIA were tested using a one foot long, 15kV arc blast, generating 8,000 amps, creating arc exposure energies ranging from 36 cal/cm2 to 150 cal/cm2 (distance of 6 to 15 inches from the arc) with an arc duration of 1/6 of a second. This arc blast approximates the potential exposure that may occur from retail power lines (4 to 12kV), where many arc-related accidents occur.
Everyday Cotton fabrics both ignited and blasted apart following exposures as low as 50 cal/cm2 (fabric 12 inches from the arc). None of the flame resistant fabrics, including Nomex® IIIA, ignited following exposure to the electric arc. And lower energy arc exposures (less than 76 cal/cm2) were not sufficient energy to blast apart any of the protective fabrics tested.
However, higher energy arc exposures indicate that fabrics of Nomex® IIIA have a greater likelihood of staying intact than comparable weight flame retardant treated Cotton fabrics. Repeated tests conducted at exposure energies of 96 cal/cm2 show that none of the 203gsm/6oz fabrics of Nomex® IIIA blasted apart while all of the 203gsm/6oz fabrics of flame retardant Cotton failed.
Finally, at very high arc energy exposures (150 cal/cm2), although none of the lighter weight protective fabrics had sufficient strength to withstand the blast, heavier fabrics of Nomex® IIIA (254gsm/7.5oz) did not blast apart. In contrast, all flame retardant treated Cotton fabrics (weighing up to 373gsm/11oz) failed when exposed to arcs with this much energy.
These tests indicate that fabrics of Nomex® IIIA can provide greater protection from break-open in electric arc exposure than comparable weight fabrics of flame retardant treated Cotton.
Workers working in areas where there are electric hazards should be provided with the right types of electric arc garments meeting the risk protection categories identified in those work areas. Electric arc garments made of Nomex® IIIA fabrics, to the electric arc categories, will be an excellent investment. NFPA 70E standards should be a reference in this instance.
In a flash fire situation, a matter of seconds can mean the difference between minor burns and life-threatening injuries. By far the greatest factor affecting survivability is the percentage of the body that receives second and third-degree burns. The lower the level of total body burn, the greater the chance of survival.
Flame resistant garments of Nomex® IIIA help protect the wearer from the heat and flame of a flash fire, providing valuable seconds of protection for escape and minimising the potential for burn injury. The thermal protective properties of fabrics and fabric systems can be demonstrated through the use the Thermal Protective Performance (TPP) Test, as described in NFPA Standard 1971 and ASTM D4108. The Thermal Protective Performance Test measures how well a fabric or fabric system can protect the wearer against second-degree burns in a flash fire. The higher the TPP value, the more thermal protection the fabric provides relative to other fabrics.
Years of TPP testing have shown that Nomex® IIIA consistently outperforms chemically dependent fabrics, even when a lighter weight fabric of Nomex® IIIA is compared to a heavier weight, chemically dependent fabric.
Thermal Protective Performance Ratings of Single-Layer Fabrics
ASTM D4108 with Combined Convective and Radiant Heat Source
Recommended Configuration for Single-Layer Fabricsª
|65%/35% Polyester/Cotton||N/A - Ignites|
|100% Cotton||N/A - Ignites|
ª 2.0 cal/cm2 heat flux. Fabrics were home laundered once only prior to testing. N/A - Not Applicable.
Limiting Oxygen Index (LOI)
The Limiting Oxygen Index of Nomex® and Kevlar® fibre is approximately 30. The Limiting Oxygen Index is a measurement of the minimum concentration of oxygen, expressed as a percentage, needed in the atmosphere to support combustion of the fibre. These indexes mean that a minimum concentration of 30% oxygen would be required to maintain the combustion of a Nomex® and Kevlar® sample when each are exposed to a flame in a vertical plane. Since atmospheric air contains an oxygen concentration of 20.95%, any textile with a greater value of Limiting Oxygen Index can be considered non-flammable. This property prevents combustion and therefore propagation of fire to a wider environment.
The fact that Nomex® and Kevlar® fibre will not burn in air means they will not burn like Cotton fabric nor melt or drip like a polyester fabric. When exposed to a flame source, Nomex® fibre absorbs the heat energy and the fibre swells up, thickening in the process, which in turn helps to stop heat transfer to the wearer. At temperatures above approximately 427° C (800° F), Nomex® fibre will simply form a very tough carbonaceous char which is the essence of its fire protective mode of action.
Control of Static
Many natural and synthetic fibres rely on moisture absorption for their anti-static properties because water conducts and helps distribute static charge. Unfortunately, garments made from natural fibres, such as Wool or Cotton, or synthetic fibres that rely on water content for their natural anti-static properties are not anti-static at low humidty temperatures.
Even at low humidity levels, Nomex® IIIA maintains its anti-static properties. This is because the P-140 static-dissipative fibre is blended into Nomex® IIIA and is effective at humidity levels as low as 20 percent.
The Anti-Static Charge Decay test conforms to US Federal Test Standard 191A, Method 5931, which involves the test fabric being supported between two parallel electrodes and then exposed to a 5 kV source. Dupont™ requires that Nomex® IIIA must accept a minimum of 3 kV and be able to discharge 10% of this voltage within half a second at the precise time the electrodes are grounded. This test procedure is performed in a controlled environment of 21° C (70° F) and 20% relative humidity.
Anti-Static Charge Decay Test Results for Nomex® IIIA
|Number of||kV||Seconds to 10% of|
|Launderings||Accepted||Initial kV Accepted|
WARNING - it is important to remember that anti-static clothing does not eliminate the charge build-up on the body, nor does it change the stored electrical energy on ungrounded objects that are nearby, such as buckets or lockers. Proper grounding procedures - such as discharging static from the body before entering a potentially explosive atmosphere (by touching a grounded metal object), wearing a wristlet connected to a ground source using conductive footwear and flooring - also are important safety controls needed to reduce spark potential.
How MP3 Protects
DuPont’s Nomex® wants you to feel that your clothing is there for you when you need it, so you can perform to your fullest potential when facing intense heat and flames. Nomex® thermal technology has a 40-year history demonstrating proven protection against electric arc flash and flash fire. Inherently flame resistant Nomex® is valued by military personnel, those employed by the chemical and petrochemical industries, electrical utility workers and firefighters because it protects them from thermal hazards associated with electric arc flash and flash fire. Nomex® is also worn by F1®, NASCAR® and MotoGP™ drivers, riders and pit crew who, for decades, have relied on racing apparel made with DuPont™ Nomex® brand fibre to help keep them safe from harm. Only one brand provides this level of protection and that brand is Nomex®.
3M™ Scotchlite™ reflective material makes people visible – it reflects light back to its source such as vehicle headlights, making the garment wearer visible to the motorist more easily and earlier. As a result, motorists have more time to react.
MP3 Care Instructions
Machine warm wash with like colours (120° F / 49° C).
Non-chlorine bleach only.
Tumble dry on low (140° F / 60° C).
Do not dry in sunlight.
Use a steam iron on medium.
Do not dry clean.
MP3 Extended Care – hang garment after each use and keep clean for optimum performance. For maximum performance it is recommended that MP3 be laundered after exposure to any liquid other than water.
End User Intended Use
¹ The chemical resistance discussed here is the resistance of the fibre to degradation by specific chemicals, not the resistance of fabrics of Nomex® IIIA to penetration by those chemical solutions. Specifically designed, laminated or coated fabrics of Nomex® IIIA are available for use in protective apparel applications where barrier protection against hazardous chemical penetration is required.
² THERMO-MAN® is a life-sized, instrumented mannequin system and one of the most advanced thermal burn injury evaluation devices in the world. Covered with 122 sensors and dressed in test garments, DuPont™ THERMO-MAN® helps ensure optimal product performance.