BS EN 17190:2018 pdf download.Flexible sheets for waterproofing – Solar Reflectance Index
1 Scope
This European Standard gives a calculation method of the Solar Reflectance Index (SRI) and the determination of solar reflectivity and thermal emissivity for waterproofing flexible sheets for roofs with a slope smaller than 10°.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
EN 15976, Flexible sheets for waterproofing一Determination of emissivity
ASTM C1549- 16, Standard test method for determination of solar reflectance near ambient temperature using a portable solar reflectometer
ASTM E1980-11, Standard practice for calculating Solar Reflectance Index of horizontal and low-sloped opaque surfaces
ASTM E903-12, Standard Test Method for Solar Absorptance, Reflectance, and Transmittance of Materials Using Integrating Spheres
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
●IEC Electropedia: available at http://www.electropedia.org/
●ISO Online browsing platform: available at http:/ /www.iso.org/ obp
3.1 Solar Reflectance Index
relative temperature of a surface with respect to the standard white (SRI = 100] and standard black (SRI = 0) under the standard solar and ambient conditions
[SOURCE: ASTM E1980-11, definition 3.1.9]
3.2 solar reflectivity
ratio of the reflected irradiation to the solar irradiation from a surface of the sheet
3.3 thermal emissivity
emissivity of a material (usually written E) is the ratio (proportion) of the energy radiated by a surface relative to the energy radiated by a blackbody at the same temperature; it is a measure of a material’s ability to radiate heat
[SOURCE: EN 15976:2011, definition 3.1]
4 Sampling
For initial values, take a (new) roll directly from the storage of the manufacture. Unroll the roll over at least 0,5 m and take 5 samples over the width of the sheet.The surface should be clean to keep the radiative properties of the sheet.
5 Solar reflectivity
Solar reflectivity is measured according to:
一ASTM C1549-16; or
一ASTM E903-12.
Both shall be measured with the solar spectrum according to ASTM E1980-11.
NOTE1 In the European interlaboratory test it was found within the scattering of the test methods the same results, see [1].
NOTE 2 For the variation of the solar reflectivity, see [1].
6 Thermal emissivity
Thermal emissivity is measured according to EN 15976.
NOTE 1 Thermal emissivity measured according to ASTM C1371 gives within the scattering of the test methods the same results, see [1].
NOTE2 For the variation of the thermal emissivity, see [1].
BS EN 17190:2018 pdf download
