Resistance static puncture

The static puncture test is described in EN ISO 12236 Geotextiles and Geotextiles-Related Products - Static Puncture Test. A cylindrical stamp (50 mm in diameter) is pressed through a clamped geomembraue disk of 150 mm fiee diameter at a speed of 50 mm/min. Thereby the resistauce to quasi-static puncture by a small, sharp edged object is determined. The maximum force required (puncture resistance) is the test parameter. The 2.5 mm thick HDPE geomembianes typically reach values > 6000 N. 

Sturdy safety shoes should have impact-resistant toes and heat-resistant soles to protect against hot work surfaces common in roofing, paving, and hot metal industries. The metal insoles of some safety shoes protect against puncture wounds. Safety shoes may also be designed to be electrically conductive to prevent the buildup of static electricity in areas with the potential for explosive atmospheres, or noncon-ductive to protect workers from workplace electrical hazards. All safety shoes must comply with the ANSI standard(s) mentioned above. In addition, depending on the types of worker exposures, there may be a need to provide specially designed safety shoes such as conductive or electrical-hazard safety shoes. 

The above figures record the relative penetration of a sharp needle under static load into a variety of plastics. The lowest number indicates maximum puncture resistance. 

Copolymers of butadiene, acrylonitrile and a third monomer that contains a carboxylic acid group (usually methacrylic acid). Gloves made from this copolymer are often termed nitrile . The particular advantages of this polymer are resistance to many solvents and excellent mechanical protection (abrasion and puncture resistance). Nitrile also has a significantly lower surface electrical resistivity than natural rubber, and therefore finds use in gloves for use in areas where static electricity might be a problem. 

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