Building materials, depending on the position, inclination and direction of the surface, are subject to variations in temperature and humidity, as well as to UV radiation, duration and different intensity. Because of the variation of these influences and their combinations, it is important to be tested resistance to environmental conditions of the painting of masonry and concrete in order to confirm that meet specified requirements.

The samples to be subjected to this type of test are small panels of size 140 mm x 70 mm. They are prepared by applying to the substrate the product or paint system to be tested in accordance with the manufacturer's instructions and let them to cure for 7 days at temperature of 23 ± 2°C and a relative humidity of 50 ± 5%.

The samples are inserted in an instrument characterized by a chamber with three fluorescent UV lamps, which serve as light sources, and a system for spraying water into the chamber. It sets a cycle according to which samples are subjected for 4 hours to exposure of UV radiation and for 4 hours at spray of water, and then to wetting, without UV radiation. The complete cycle has a total duration of exposure at least 1000 hours before to carry out further testing.

During the step of (dry) irradiation the temperature of black panel is maintained at temperature of 60 ± 3°C for a period of 4 hours, unless otherwise agreed. Subsequently the samples are air-conditioned at temperature of 23 ± 2°C and a relative humidity of 50 ± 5% for at least 24 hours before any further tests.

This method allows to be drawn conclusions on the surface degradation through mechanical properties changes of the coatings due to UV radiation. It is particularly suitable for coatings that react to UV radiation.

 

Material type Standard Test method
self-levelings EN 13813
  •  
waterproofing EN 14891
  •  
paints/varnishes - EN 1062-11
surface protection mortars EN 1504-3 EN 1062-11

 

Instruments used to perform the test: UV-ray chamber

 

The test consists to determine the surface degradation of materials after being subjected to UV radiation and dampness.The test consists to determine the surface degradation of materials after being subjected to UV radiation and dampness.The test consists to determine the surface degradation of materials after being subjected to UV radiation and dampness.

The test consists to determine the surface degradation of materials after being subjected to UV radiation and dampness.

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