17.11.11 by ellie
It is important to ensure that the right hand protection is of primary concern in every workplace. Lacerations are the #1 safety issue in most plants with common causes ranging from hand protection not being worn, poor compliance to PPE (personal protection equipment) programs and PPE simply misapplied. The COSTS of not doing so could be extremely heavy and are often not fully realized until after the fact. The Iceberg Principle for costs of injuries includes direct costs such as medical costs, workmen’s compensation and worker’s loss time. Indirect costs include hours lost to first aid, hours lost to assisting and transporting victims, hours lost to handling inquiries, cost of damaged equipment, administrative costs and lost hours used for investigation. These costs far outweigh the price of proper hand protection on all hands.
On numerous occasions safety professionals in the supply chain walk into work situations where cost and safety are primary concerns. While most if not all companies put safety first, there is definitely a cost sensitivity that is hard to ignore. Advanced textile materials have come a long way in providing solutions that offer optimum protection at continuously more affordable prices. It therefore helps to have an understanding of these materials, the way they are tested and what those tests mean.
Two methods are used in Europe to measure cut resistance on gloves.
The EN 388 blade cut resistance or ‘Coup test’ has been in regular use for more than ten years. It involves a circular blade moving back and forth over the sample, rotating in the opposite way to the direction of travel, under a fairly light (5N) cutting force. A blade cut index is calculated depending on the number of 50mm cutting strokes needed to penetrate the samples taken from the palm of a glove. To calibrate the circular blade and account for the loss in sharpness over several cutting strokes, a standard canvas is cut before and after the test sample. The average number of these calibration cuts is used as a divider to calculate the performance index. The index is then given as a level from one to five, with five being the best performer. These performance levels are recognised by safety professionals and considered a valuable tool in choosing the correct glove, following a risk assessment of the relevant activity.
EN ISO 13997
Although the EN 388 method is satisfactory for gloves with lower levels of cut resistance, improvements in glove technology have highlighted its deficiency at higher cut levels, due to the rapid blunting of the test blade. For this reason the alternative test, EN ISO 13997:1999, has proved to be more representative of the comparative cut resistance of newer materials.
The EN ISO test uses the principle of a straight blade drawn across the sample material at a constant speed and weight. The distance travelled to cause cut through is then recorded and the results are calculated to give the force required to cut through at 20mm of blade travel. A force of >13 N denotes a Level 4 cut performance, with Level 5 achieved only by registering a force of >22 N.
Due to recent harmonisation of test standards, IS0 13997 should provide similar results to those obtained in North America using the ASTM F1790 standard.
Technical Director, Tilsatec