ISO 12571-2013 pdf free download

ISO 12571-2013 pdf free download.Hygrothermal performance of building materials and products Determination of hygroscopic sorption properties
Performance hygrothermique des maté riaux et produits pour le bâtiment — Determination des propriétés de sorption hygroscopique.
4 Principle
4.1 Sorption curve
The specimen is dried to constant mass. While maintaining a constant temperature, the specimen is placed consecutively In a series of test environments, with relative humidity increasing in stages. The moisture content is determined when equilibrium with each environment is reached. Equilibrium with the environment is established by weighing the specimen until constant mass is reached. A minimum of four test atmospheres shall be selected in the humidity range under consideration.
Alter establishing the moisture content at each relative humidity the sorption curve can be drawn.
4.2 Desorption curve
The starting point for desorption is a relative humidity of at least 95 %. This might be the last point of the sorption curve or might be reached by sorption from a dried test specimen. While maintaining a constant temperature, the specimen is placed consecutively in a series of test environments, with relative humidity decreasing in stages. The moisture content is determined when equilibrium with each environment is reached. Equilibrium with the environment is established by weighing the specimen until constant mass is reached. A minimum of four test atmospheres shall be selected in the humidity range under consideration. Finally, the specimen is dried to constant mass.
Alter establishing the moisture content at each relative humidity the desorption curve can be drawn.
NOTE A defined starting point for desorption has been chosen for better reproducibility.
5 Apparatus
5.1 Desiccator method
The test apparatus shall include:
a) weighing cups which do not absorb water and with tight-fitting lids;
b) balance, capable of weighing to an accuracy of± 0,01 % of the mass of the test specimen; NOTE It larger weighing cups are used, the weighing accuracy can he determined with respect to the total mass and the required accuracy of the test results.
c) drying oven, in accordance with ISO 12570;
d) desiccator, capable of maintaining the relative humidity within ± 2 % relative humidity;
e) constant-temperature chamber, capable of maintaining the specified test temperature to an accuracy of±0,5 K.
5.2 Climatic chamber method
The test apparatus shall include:
a) weighing cups which do not absorb water;
b) balance, capable of weighing to an accuracy of ± 0,01 % of the mass of the test specimen;
NOTE If larger weighing cups are used, the weighing accuracy can be determined with respect to the total mass and the required accuracy of the test results.
c) drying oven, in accordance with ISO 12570;
d) climatic chamber, capable of maintaining the relative humidity within ± 5 % relative humidity and the temperature within ± 2 K over the whole test area.
6 Test specimens
6.1 Specification of the test specimens
A test specimen shall be representative of the product and have a mass of at least 10 g. Specimens of materials with a dry density less than 300 kg/rn3 shall have an area of at least 100mm x 100 mm. If it can be demonstrated from other references that the result will not be affected, a test specimen can be cut or crushed into smaller pieces to reduce the time to reach equilibrium with the environment.ISO 12571-2013 pdf free download.