EN 374:2016 Explained

Thursday, 8 March 2018

The standard to which protective gloves are tested to determine and rate their resistance to chemicals and micro-organisms has changed. While gloves previously classified according to the old standard of EN 374:2003 can be sold until the effects of the new PPE regulation make reclassification mandatory, gloves tested after February 2016 are classified according to the more comprehensive EN ISO 374:2016.

What is EN 374?

EN 374 is a standard used to classify gloves according to the protection that they provide against chemicals and micro-organisms. In order for gloves to be classified under EN 374, they have to undergo various permeation tests. Once tested, gloves are provided with a rating for their resistance to permeation by specific chemicals and micro-organisms to promote consumer safety. Gloves that have undergone this testing will be marked with the beaker symbol below:

EN 374 Beaker Symbol for Chemical Resistance

What's Changed?

So, EN 374:2003 is on its way out and EN 374:2016 is appearing on more and more conformity statements, but what's actually changed? Basically, EN ISO 374:2016 requires permeation tests to be carried out for more chemicals than EN 374:2003; the new standard adds an extra classification level according to the class of chemicals that the gloves protect against; and protection against permeation by micro-organisms is specified as protection against virus, bacteria and/or fungi. Here are the specifics:

Chemical Resistance Rating

Under EN ISO 374:2016, gloves are tested for their resistance to 18 different chemicals, as opposed to the 12 chemicals tested under EN 374:2003. As a result, the new permeation table includes six new categories. Below is the complete list of chemicals against which gloves are now tested:

Code letter Chemical CAS Number Class
A Methanol 67-56-1 Primary alcohol
B Acetone 67-64-1 Ketone
C Acetonitrile 75-05-8 Nitrile compound
D Dichloromethane 75-09-2 Chlorinated hydrocarbon
E Carbon disulphide 75-15-0 Sulphur containing organic compound
F Toluene 108-88-3 Aromatic hydrocarbon
G Diethylamine 109-89-7 Amine
H Tetrahydrofuran 109-99-9 Heterocyclic and ether compound
I Ethyl acetate 141-78-6 Ester
J n-Heptane 142-82-5 Saturated hydrocarbon
K Sodium hydroxide 40% 1310-73-2 Inorganic base
L Sulphuric acid 96% 7664-93-9 Inorganic mineral acid, oxidising
M Nitric acid 65% 7697-37-2 Inorganic mineral acid, oxidising
N Acetic acid 99% 64-19-7 Organic acid
O Ammonium hydroxide 25% 1336-21-6 Organic base
P Hydrogen peroxide 30% 7722-84-1 Peroxide
S Hydrofluoric acid 40% 7664-39-3 Inorganic mineral acid
T Formaldehyde 37% 50-00-0 Aldehyde

As well as adding more comprehensive chemical testing, EN 374:2016 also includes a new category, where gloves are rated either Type A, Type B, or Type C – depending on the number of chemicals that they provide protection against. Most chemical-resistant gloves will be classified as Type A – gloves that protect against permeation by at least six of the above chemicals for a period of 30 minutes or more.

EN ISO 374:2016 makes use of the same beaker symbol as EN 374:2003, with the letters of the chemicals it has passed resistance tests for denoted underneath. However, the classification of Type A, Type B or Type C is added to the top of the symbol for gloves that have been tested to EN 374:2016. Here is what the new symbol looks like:

EN 374 2016 Beaker Symbol Type A

Degradation Testing

A new degradation test has been introduced under EN 374:2016, where any changes in the physical properties of a glove after exposure to a particular chemical are recorded. Changes noted include swelling, cracking, brittleness or shrinkage.

Permeation Testing Method

Under EN 374:2003, three samples from the palm or weakest area of the glove were used to test the resistance of a glove to chemical permeation. Under EN ISO 374:2016, three specimens from the palm are tested for chemical permeation and gloves that are 400mm or longer, or have a cuff intended to protect the wearer against chemical risks, will require additional testing to determine the permeation level of the cuff in comparison to the palm. If the palm and cuff achieve different results, then the lower result will be used to classify the glove.

Protection Against Micro-Organisms

While EN 374-1:2003 tested gloves for their resistance to micro-organisms, EN ISO 374-5:2016 specifically classifies gloves according to whether they provide protection against bacteria, fungi and/or viruses for greater safety. The specific micro-organism that the glove provides protection against (if any) will be listed below the biohazard symbol shown below.

EN 374 Biohazard Virus, Fungus and Bacteria Symbol

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