The water resistance test is designed to determine the suitability of cable materials for long-term immersion in water, also known as the mechanical properties of the cable sheath after immersion in water. The test method is carried out in accordance with the European Standard BS EN 60811-501 and requires the use of a hot water bath and tensile testing machine.

The following are the main steps and requirements for water resistance testing:

Sample Preparation: Four sets of dumbbell shaped samples are taken from the sheath of the selected cable, each set comprising three samples.

Ambient conditions: These samples are placed in ambient conditions at a temperature of (20 ± 2)°C and a relative humidity of (50 ± 5)% for 7 days.

Weighing and immersion in water: after conditioning, a set of samples was weighed to the nearest 0.1 mg and immersed in drinking water at (50 ± 2)°C for 100 days.

Conditioning: After removing the samples from the water bath, surface water was removed and the samples were further conditioned for 16 hours at a temperature of (20 ± 5)°C and a relative humidity of (50 ± 5)%.

Re-weighing: The samples were re-weighed and their weights were recorded to the nearest 0.1 mg.

Change in mass: The increase in mass of the samples after immersion should not exceed 40% of the mass of the samples before immersion. 

Tensile testing: Three additional sets of samples were used to perform tensile strength and elongation at break tests, respectively:

i) not immersed

ii) after 28 days of immersion in drinking water at (50±2)°C

iii) After soaking in drinking water at (50±2)°C for 100 days

Evaluation of results: Calculation of tensile strength and elongation at break, and changes between 28 days of immersion and 100 days of immersion. The test results must fulfil the specific values specified in the standard.