Puncture resistance
Encyclopedia
Puncture resistance denotes the relative ability of a material to inhibit the progression of a tear once it has been pierced by a cut or a nick. Tests devised to measure puncture resistance are generally application-specific, covering items such as roofing and packaging materials, protective gloves, needle disposal facilities
Sharps waste
Sharps waste is a form of medical waste composed of used sharps, which includes any device or object used to puncture or lacerate the skin. Sharps waste is classified as biohazardous waste and must be carefully handled...

, etc. Puncture resistance in fabrics can be obtained through very tight woven fabrics, small ceramic plates in fabric coating or tight woven fabrics with a coating of hard crystals. All described methods significantly reduce the softness and flexibility of the fabric.

The puncture resistance will depend on the nature of puncture attempt, with the two most important features being point sharpness and force. A fine sharp point such as a hypodermic needle
Hypodermic needle
A hypodermic needle is a hollow needle commonly used with a syringe to inject substances into the body or extract fluids from it...

 will require a high ability to absorb and distribute the force to avoid penetration, but the total forces applied are still limited. The EN388 glove standard use a more pencil-like object with a flat tip of 1mm diameter. The EN388 test is highly dependent on the materials ability to withstand high forces through high tenacity and to a lesser extent to avoid cut or separation of the material.

There is no or limited correlation between the protections provided in the low force/needle protection and the high force/pencil like EN388 test.

Needle-resistant materials as described above are generally pierced by a force between 2-10N by a 25 gauge needle perpendicular to the fabric. The forces in the EN 388 test results are rated according to a score from 0-4 (0-<20N, 1-20N, 2-60N 3-100N 4-150N+). Three layers of SuperFabric
SuperFabric
SuperFabric is a cut and abrasion resistant material, and a registered trademark of Higher Dimension Materials, Inc. As a technical fabric, SuperFabric is created with a base fabric such as nylon, polyester, neoprene, crepe, etc. and is overlaid with tiny, hard guard plates in a specific pattern...

 have a higher needle protection than single layers of woven para aramid (Kevlar
Kevlar
Kevlar is the registered trademark for a para-aramid synthetic fiber, related to other aramids such as Nomex and Technora. Developed at DuPont in 1965, this high strength material was first commercially used in the early 1970s as a replacement for steel in racing tires...

) and SuperFabric has a significantly higher level of protection against the pencil-like high force EN388 test compared to the coated woven para aramid.
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