scope:

This International Standard specifies methods for the assessment of surface defects (crazing and cracking) on sealants after exposure to artificial or natural weathering.

NOTE Sealants are weathered in the laboratory in order to simulate ageing processes occurring during natural weathering. Generally, valid correlations between ageing during artificial and natural weathering cannot be expected because of the large number of influencing factors. Certain relationships can only be expected if the effect of the important parameters (spectral distribution of the irradiance in their photochemically relevant range, temperature of the specimen, type of wetting, wetting cycle relative humidity) on the sealant is known. However, unlike natural weathering, testing in the laboratory is carried out taking into consideration a limited number of variables which can be controlled, and therefore, the results are more reproducible.