BS ISO 9370:2017 pdf free

BS ISO 9370:2017 pdf free.Plastics – Instrumental determination of radiant exposure in weathering tests
Fresnel-reflecting concentrator devices use a series of mirrors to focus solar radiation on an exposure area. Measurements of the direct component of both total solar and solar ultraviolet radiation are required when performing accelerated natural weathering tests employing Fresnel-reflecting concentrators in accordance with recognized standards.
The direct component of total solar radiation is measured with a pyrheliometer. The direct component of solar ultraviolet radiation is measured using two ultraviolet radiometers, one of which is fitted with a shading disk to block direct solar ultraviolet radiation. The direct component is determined as the difference between the readings from the two instruments. The pyrheliometers and ultraviolet radiometers must be mounted on a sun-tracking device.
NOTE For solar concentrating exposures using Fresnel-reflecting concentrators, the direct component of solar radiation is the direct normal solar radiation.
For the requirements of recognized standards to be met, it is essential that the field of view of the radiometers used be approximately equal to that of the Fresnel-reflecting concentrators employed and that the tracking accuracy of the sun tracker be equal to or better than that of the Fresnel-reflecting concentrators employed.
For artificial accelerated weathering and artificial accelerated irradiation exposures,measurements of ultraviolet and visible radiation using the instruments and procedures described in this document may aid in improving the reproducibility of these exposures. However, monitoring irradiance in a single passband is usually not sufficient to detect all differences caused by variation in filter type or solarization of filters. Changes in radiation caused by filter variation can be detected by monitoring radiation simultaneously in a short-wavelength passband and a long-wavelength passband.
Irradiance can be measured in any wavelength region of interest. Because of the greater sensitivity of polymer materials to ultraviolet radiation, it is the intent of this document to emphasize the measurement of irradiance and radiant energy in the total ultraviolet region from the short-wavelength cut-on of the detector (e.g. approximately 300 nm) to 400 nm wavelength, or in selected regions of the ultraviolet or visible passband.BS ISO 9370 pdf download.