EN ISO 374-4
EN ISO 374-4:2013 sets the test procedure for determining the resistance of protective glove materials to degradation by chemicals.
Test procedure:
1. The glove material is exposed to a defined chemical for a specified time
2. Afterwards the following are measured:
- Wall thickness change (percentage increase or decrease)
- Tensile strength change (percentage loss of tensile force)
3. The greater the change, the poorer the degradation resistance
Practical significance:
Degradation is an indirect protection mechanism: a degraded material increases permeation rates and facilitates penetration. Degradation data should therefore always be considered together with permeation data.
Typical degradation scenarios:
- Nitrile: swells and loses strength with ketones and polar solvents
- Latex: degrades rapidly on mineral oil contact
- Neoprene: generally good degradation resistance but susceptible to chlorinated hydrocarbons
- Butyl: excellent resistance to polar substances
Degradation data are practically relevant for selecting the correct glove material for specific chemicals.
Frequently asked questions
What exactly does the degradation test per EN ISO 374-4 measure?
The test measures the percentage change in wall thickness and tensile strength after contact with a defined chemical. The smaller the change, the better the material's degradation resistance.
Why is degradation important if permeation and penetration are already tested?
Degradation is a precursor: a degraded material offers poorer permeation protection and is more susceptible to penetration. Degradation data help with material selection and determination of maximum wearing times.
Are there degradation classes like permeation classes?
No. EN ISO 374-4 does not define classes as for permeation. The test result is a quantitative value (percentage change) reported in manufacturer-specific chemical resistance charts.