Chemical or micro-organism exposure can be harmful and, in some cases, may even be fatal. Gloves that claim to offer protection against chemical and/or micro-organisms should, therefore, be tested according to the EN 374 standard. This European standard determines the types of chemicals and micro-organisms the gloves are protective against, along with their permeation, penetration, and penetration resistance.
The EN 374 standard
EN 374 is the European standard that specifies the capability of gloves to protect the wearer against micro-organisms and/or chemicals.
Before protective gloves can be classified under EN 374, they must undergo various tests. These tests are used to determine the gloves’ resistance to permeation, penetration, and degradation.
EN 374:2016
EN 374 was updated in 2016 to The EN 374:2016, bringing in several amendments to the previous standard.
Under EN 374:2016, amendments included a modification to the name of the standard from “protective gloves against dangerous chemicals and micro-organisms” to “protective gloves against chemicals and micro-organisms”. Other amendments include introducing a classification type for the gloves and increasing the number of test chemicals from 12 to 18.
The EN 374 sections explained
The EN 374 standard consists of five sections which are used to determine the suitability of the gloves to protect the wearer against specific chemicals and micro-organisms.
EN 374-1: Protective gloves against chemicals and micro-organisms
EN 374-1 specifies the requirements for protective gloves that are intended to protect the wearer against chemicals and micro-organisms.
Under this section of EN 374, protective gloves are tested against 18 different chemicals before being certified with a rating of A, B, or C depending on how resistant they are to chemicals.
Most chemical-resistant gloves will be classified as Type A, meaning they have a permeation resistance of at least 30 minutes against at least six of the tested chemicals.
|
EN374-1 rating |
Minimum resistance to permeation |
|
Type A |
Protective gloves with a permeation resistance of at least 30 minutes with at least six test chemicals |
|
Type B |
Protective gloves with a permeation resistance of at least 30 minutes with at least three test chemicals |
|
Type C |
Protective gloves with a permeation resistance of at least 10 minutes with at least one test chemical |
The rating of the gloves will also determine the marking used. This marking will feature a series of code letters underneath the pictogram to indicate which chemicals the glove that can be used with.
The chemicals that gloves are tested against, and their corresponding code letter, CAS (Chemical Abstracts Service) number, and class are detailed in the below table.
|
Code letter |
Defined 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 |
Ammonia 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 |
EN 374-2: Determination of resistance to penetration
EN 374-2 specifies the test method that should be used to determine the penetration resistance of gloves that protect against chemicals and/or micro-organisms.
The test methods used under EN 374-2 is a water leak and air leak test. This test is performed to ensure there are no direct paths for chemicals to penetrate the glove.
Mechanical damage such as stretching, cuts, or punctures can cause macroscopic breaks, making them more vulnerable to chemical and/or micro-organism penetration. Gloves that have been poorly made are more likely to fail due to penetration as the material will be less likely to withstand mechanical damage.
The penetration resistance of the gloves is further checked in the QA process to ensure the gloves in each production run have been made according to the specified standard.
EN 374-3: Determination of resistance to permeation
EN 374-3 specifies the test method that should be used to determine the permeation resistance of gloves that protect against chemicals.
Under the EN 374:2016 update, the EN 374-3 standard has been replaced by EN 16523-1. This replacement safety standard specifies the test method to determine the resistance of protective gloves to permeation.
Under the EN 16523-1 standard, permeation resistance is tested by placing the glove in contact with a chemical and measuring the rate at which this chemical travels through (permeates) the glove. The breakthrough time of the chemical through the glove material is used to classify the permeation resistance rating of the gloves.
EN 374-4: Determination of resistance to degradation
EN 374-4 specifies the test method that should be used to determine the degradation resistance of gloves that protect against chemicals.
This section of EN 374 takes into consideration how the glove material changes due to chemical exposure. Degradation can, for example, cause brittleness, swelling, or shrinkage of the glove material, compromising its protectiveness against the chemical.
Any protective gloves that claim to offer chemical protection need to be assessed for degradation resistance, as per the EN 374-4 test method. EN 374-4 measures degradation resistance by testing whether there is a change in the force required to puncture the glove material after continuous contact with a challenge chemical.
The degradation resistance should be reported in the User Instruction, ensuring the degradation percentage results (percentage of change in puncture test before and after chemical exposure) are available for the wearer.
EN 374-5: Terminology and performance requirements for micro-organism risks
The EN 374-5 section of EN 374 specifically classifies protective gloves based on whether they provide protection against micro-organism risks such as bacteria, fungi, and viruses.
This section of EN 374 requires any gloves claiming to offer micro-organism protection to undergo penetration testing, as per the EN 374-2 test method.
The specific micro-organisms that the gloves provide protection against will be shown by a biohazard marking.
Gloves that offer protection against viruses should also pass a penetration test according to ISO 16604:2004 - determination of resistance of protective clothing materials to penetration by blood-borne pathogens.
