Cut protection for gloves — standard update

A revision to the EN388 standard for gloves giving protection from mechanical risks such as cuts is expected to increase the accuracy and reliability of cutting tests on higher resistance materials. The revision, which should be published around mid-2016, has been welcomed by DSM Dyneema, a member of the Technical Committee charged with revising the standard.

The science-based company active in health, nutrition and materials, and also known as the producer of Dyneema, a lightweight polyethylene fibre used in many of the most cut-resistant protective gloves, believes EN388 2016 will help glove specifiers and users choose the products best suited to their needs.

“We believe that EN388 2016 will help protective glove users make better and more informed choices about the products they purchase and put so much faith in,” said Olivier Boubeaud, global segment director, high protective textiles for DSM Dyneema.

“But we also appreciate that quite a number of things are changing, and that the timetable is still not clear, so we strongly advise glove users to ask their suppliers for the relevant documentation so that they can better understand the situation.”

EN388 details test procedures that enable laboratories to classify protective gloves according to their resistance to cutting, abrasion, tearing and puncturing. It is the de facto standard used in most parts of the world but has not been revised since 2003. Advances in materials used to make high-quality, cut-resistant gloves since the last revision have created the need for modifications to the cut test, in order to accurately measure the increased safety that they provide.

According to DSM Dyneema, in its present form EN388 describes the Coup Test method for assessing protective gloves with a wide range of cut resistance. In this test, cut resistance of a sample taken from the glove is measured by a rotating circular blade, similar to a pizza cutter, moving back and forth over it with a constant force, until the blade cuts all the way through. The result is expressed on a scale from 0 to 5, with 5 indicating the highest resistance. This number is known as a ‘Cut level’.

Figure 1: A schematic of the test and a table showing the relationship between average cut index and cut level.

This test runs into problems when testing high-performance materials, as well as glass and stainless steel fibres, all of which have a dulling effect on the blade. In some cases, the blade may not even be able to cut through the material.

EN388 has therefore been revised to include modifications to the Coup Test — with specifications, for example, on when the blade needs to be changed — as well as the inclusion of a second test. It also includes modifications to the ISO Cut Test, specified in EN ISO 13997 (also known as the TDM test). This second test is already included in the current version of EN388, but only as a voluntary complement to the Coup Test. However, in the 2016 version of EN388, it will have to be used on materials with high cut resistance. The Coup Test will continue to be mandatory for less resistant gloves, for which the ISO Cut Test will remain voluntary.

“The Coup Test is a good test for gloves with lower levels of cut resistance, but it is not adequate for higher performance gloves such as those made from Dyneema Diamond Technology,” said Boubeaud.

“Making the ISO Cut Test compulsory for higher performance materials rectifies this anomaly. Furthermore, the inclusion of rules about how often cutting blades need to be changed will improve the consistency of results.”

Instead of using a blade under a fixed force travelling a variable distance, the ISO Cut Test uses a (flat) blade travelling a fixed distance under a variable force. It is designed to better simulate an accidental cut or slash with a sharp object. The company said scores that gloves achieve under the ISO Cut Test should be more indicative of performance in real-life situations than those achieved with the Coup Test, while results obtained are more consistent and therefore less dependent on the testing laboratory.

Figure 2: Schematic of the cutting mechanism — applying a certain load onto a sharp blade that travels over a test sample.

Cut resistance levels measured according to the ISO Cut Test will be indicated by a series of letters from A to F, with F indicating the highest level of cut resistance. This is intended to avoid any confusion with numeric ratings given with the Coup test.

Figure 3: A table showing the classification of cut resistance according to the ISO Cut Test, indicating the cutting force associated with each letter.

DSM Dyneema said it expects that gloves in future will fall into one of four categories according to cut performance:

• A: Multipurpose gloves with limited cut resistance.
• B/C: Most common applications in industries requiring medium cut resistance (eg, metal and glass processing).
• D: Gloves suitable for applications where high cut resistance is required.
• E/F: Very specific, very high risk and high exposure applications (eg, meat processing industry) that demand ultrahigh cut resistance.

The company believes most of today’s cut-resistant gloves will perform at the B or C level and advises glove users to consult with their suppliers to ensure that they obtain the right gloves for their purposes.

Gloves tested according to EN388 2016 will also be labelled with a pictogram, as shown in the below illustration, clearly indicating which cut resistance test has been used to classify the glove. Next to the number from 0 to 5 obtained from the Coup Test, there will be a letter from A to F showing the value obtained from the TDM Test.

Boubeaud, however, recommends the use of an X rather than a digit with reference to the Coup Test for gloves made with dulling materials.

“Continued publication of the numeric scores may confuse end users and possibly provide them with inaccurate information regarding the performance of the glove,” he said.

Dr Jean-Claude Cannot, who chaired the Working Group 8 of the CEN TC 162 Technical Committee charged with revising EN388, commented: “As soon as the newly revised standard is published, test houses will only be able to continue using the old standard for a further six months. We are informing all interested parties of the changes, so that glove makers can begin using the ISO Cut Test where appropriate as soon as possible.”

Image credit: ©iStockphoto.com/Robyn Mackenzie