Chemicals can be extremely harmful to both personal health and the environment. To protect the user from chemicals and micro-organisms, any kind of chemical resistant, chemical protective or chemical handling glove must meet the European glove standard EN374.
Although EN standards are not an Australian standard, it has become the benchmark in performance ratings for gloves in the manufacturing and safety industry. Standard EN374 ensures gloves are tested for their resistance to 18 different chemicals.
In 2016, EN374:2003 received some important updates to become the new chemical protective glove standard, EN374:2016. There are various changes between the 2003 and 2016 ENA374 standards including the addition of mandatory degradation testing for all rubber gloves for chemical handling. Users can notice the application of the changes to EN374 by looking at the markings on the protective gloves.
Chemical Resistance Rating
EN374 testing includes a glove rating, where the gloves are classed as either Type A, Type B or Type C. These ratings depend on the number of chemicals the glove provides protection against.
The majority of chemical-resistant gloves will be classified as Type A as these are gloves that protect the user from the permeation of at least six chemicals for a period of 30 minutes or longer.
EN374 standard safety gloves display the use of a beaker symbol inside a shield. Underneath are the letters of the chemicals it has passed the resistance test for. The Type A, B or C classification can be found above the pictogram.
Three samples from the palm of the glove are taken and tested to see if chemicals have broken through the glove material at a molecular level (this is also known as chemical permeation). Gloves that are 400mm or longer or have a cuff intended to protect the user against chemicals, will require further testing to distinguish the permeation level of the cuff in comparison to the palm of the glove. If the cuff and palm have different results, the lower result will be used to classify the glove.
In order for the glove to pass the permeation test, it must endure a minimum chemical breakthrough time of:
Type A - 30 minutes (level 2) Against a minimum of 6 test chemicals
Type B - 30 minutes (level 2) against a minimum of 3 test chemicals
Type C - 10 minutes (level 1) against a minimum of 1 test chemical
The letters under the beaker pictogram on the glove indicate which chemical the glove provides protection against - this applies only for Type A and B gloves. Type C doesn’t include letters as it only provides protection from one chemical for a short period.
For the glove to be awarded the adjacent letter, the glove must not have a permeation breakthrough of that chemical when immersed for at least 30 minutes. The following list indicates the 18 different chemicals that are tested and the corresponding letter that is used to represent that chemical. For example, gloves that provide acetone protection would be awarded the code letter B.
Chemicals have the potential to penetrate through holes or other defects in the material of the glove at a non-molecular level. For a glove to be approved as a chemical protection glove it shall not leak when tested in accordance with EN374, which includes air and water testing. For the air leak test, the glove is immersed in water whilst the interior of the glove is pressurised. A leak can then be detected by a stream of bubbles appearing from the glove's surface. When applying the water leak test, the glove is filled with water and any leaks will be discovered by droplets of water appearing on the outside of the glove.
Degradation is the process through which a change to one or more properties of the glove material occurs through contact with a chemical. Degradation testing is included in the EN374 standard, which records any changes in the physical properties of a glove after it has been exposed to a particular chemical. The changes that are recorded include flaking, shrinkage, brittleness, colour change or swelling of the glove.
Whilst there are numerous styles and types of gloves that provide protection against chemicals; nitrile chemical resistant gloves, Viton gloves or butyl gloves are among some of the most common. Nitrile rubber chemical resistance gloves however are not recommended for use with ketones, strong oxidising acids or organist chemicals containing nitrogen.
Protection against Micro-Organisms
Penetration testing is required for all gloves that claim micro-organism protection, which includes testing through air and water methods. This test specifically classifies gloves according to whether they provide protection against bacteria, fungi and in some cases viruses. If the glove provides protection against viruses, it will be shown underneath the pictogram.
Other European (EN) Glove Ratings
Additional European glove ratings include EN407 protection against heat, EN420 general requirements for all protective gloves, EN511 protection from cold, EN421 protection against ionising radiation and radioactive contamination and EN388 protection against mechanical risks.
If you’re unsure if the gloves you’re using are correct, contact the ATOM Safety team to make sure your team are equipped with the best fit-for-purpose gloves.