Learn About Glove Puncture Resistance
What is it?
To put it simply, puncture resistance is a measure of the tensile strength of a glove’s materials and how resistant the fibers are to breaking or being forced apart in order for a foreign object to penetrate through the material. It is not a rating of how puncture proof a glove or material is. Just as with cut and abrasion resistances, if something is sharp enough, moving fast enough, or persistent enough, it will get through even the best gloves – it just might take more or less force or time to get through different materials.
How is it tested?
The current method
Both ANSI and EN 388 currently use a similar test to determine overall puncture resistance. This test primarily targets puncture threats from larger sources such as nails, staples, barbed wire and similar threats. It uses a standardized 4.5mm diameter steel probe with a rounded point –roughly equivalent to a #2 pencil or ballpoint pen – moving at a set speed of 100mm/min to penetrate a sample of material at a 90 degree angle.
The testing machine records the maximum force exerted on the probe and measured in newtons that was needed to fully penetrate the material. This test is usually performed a total of 12 times on the material to get an average measurement which is then compared to a scale to determine the level of penetration resistance.
Are they equal?
The scale is the only area where the standard ANSI and EN 388 methods vary, with the ANSI scale having a 0-5 scale and EN 388 being 1-4. The ANSI system assigns a level of 0 to anything that did not withstand a minimum of 10 newtons of penetrating force, level 1 if it withstood 10-19 newtons, level 2 for 20-59 newtons, level 3 for 60-99 newtons, level 4 for 100-149 newtons, and level 5 for any material that withstood more than 150 newtons of force. The EN 388 scale assigns level 1 to any material that endured up to 20 newtons, level 2 for 20-59, level 3 for 60-99 newtons, and level 4 for anything above 100 newtons of force.
The current biggest problem with puncture resistance testing is that puncture threats don’t always come in nice, pencil sized, packages that move nice and slow which is what the currently established method is testing against. Sometimes they come thin, sharp, and in the shape of hypodermic needles expressly designed to penetrate skin. The current testing method does not address these kinds of piercing dangers which are just as dangerous as other puncture threats. Yet a glove that would better protect against them could be rated as less puncture resistant than another glove that would allow such a needle through with little force required.
In February 2016 the ANSI/ISEA 105 testing standard was updated to include a standardized test for hypodermic needle puncture resistance. Working very similarly to the existing method with the only differences being a change in probe design and the speed at which the probe travels. The new puncture probe is a 25 gauge steel needle and during testing it is moved at a velocity of 500mm/min, five times faster than the previous testing method. Using a 0-5 scale once again assigned based on newtons of force required to fully pierce the material, gloves can now be rated as to how well they protect from this increasingly common threat. The resistance levels are in increments of 2 newtons, so a level 0 is any material that resisted less than 2 newtons, 2-4 newtons is level 1, and so on up to level 5 which includes any material that resisted 10 or more newtons of force.
Is higher always better?
Just like with other types of resistance, higher is not necessarily better, as in order to get higher levels of protection, sacrifices have to be made –particularly in the area of manual dexterity or grip capability. Some of these tradeoffs are due to thicker or stiffer materials needed to provide the required level of protection. Also, some coatings used, like nitrile foam, silicone, and polyurethane have different resistances to needle puncture threats than they do nails, wood splinters, or barbed wire.
Protecting your hands while on the job, whether that’s your 9-5 or the one you do for the sheer adrenaline of the experience, is what we focus on. Puncture resistance is a critical factor in preventing hand injuries in a wide range of jobs whether that is construction, recycling, or sanitation.