Document ID: chunk:federal_register_of_legislation:F2023C00228:front:0:p28
Version: federal_register_of_legislation:F2023C00228
Segment Type: other
Provision Reference: 
Character Range: 75256–78079

temperature measured on the black panel placed on a level with the samples shall be 50 degrees C +/- 5 degrees C.  In order to ensure a regular exposure, the samples shall revolve around the source of radiation at a speed between 1 and 5 l/min.

       The samples shall be sprayed with distilled water of conductivity lower than 1 mS/m at    a temperature of 23 degrees C +/- 5 degrees C, in accordance with the following cycle: spraying:5 minutes;

       drying:25 minutes;

       2.2.2. Resistance to chemical agents

       After the test described in Paragraph 2.2.1 above and the measurement described in Paragraph 2.2.3.1 below have been carried out, the outer face of the said three samples shall be treated as described in Paragraph 2.2.2.2 with the mixture defined in Paragraph 2.2.2.1 below.

       2.2.2.1. Test mixture

       The test mixture shall be composed or 61.5% n-heptane, 12.5% toluene, 7.5% ethyl tetrachloride, 12.5% trichlorethylene and 6% xylene (volume%).

       2.2.2.2. Application of the test mixture

       Soak a piece of cotton cloth (as per ISO 105) until saturation with the mixture defined     in Paragraph 2.2.2.1 above and, within 10 seconds, apply it for 10 minutes to the outer face of the sample at a pressure of 50 N/cm2, corresponding to an effort of 100 N applied on a test surface of 14 x 14 mm.

       During this 10-minute period, the cloth pad shall be soaked again with the mixture so   that the composition of the liquid applied is continuously identical with that of the test mixture prescribed.

       During the period of application, it is permissible to compensate the pressure applied to the sample in order to prevent it from causing cracks.

       2.2.2.3. Cleaning

       At the end of the application of the test mixture, the samples shall be dried in the open air and then washed with the solution described in paragraph 2.3 (Resistance to detergents) at 23 degrees C +/- 5 degrees C.

       Afterwards the samples shall be crefully rinsed with distilled water containing not more than 0.2% impurities at 23 degrees C +/- 5 degrees C and then wiped off with a soft cloth.

       2.2.3. Results

       2.2.3.1. After the test of resistance to atmospheric agents, the outer face of the samples shall be free from cracks, scratches, chipping and deformation, and the mean variation in transmission

       measured on the three samples according to the procedure described in Appendix 2 to this Annex shall not exceed 0.020 ( depsilonlambdatauatm < 0.020).

       2.2.3.2. After the test of resistance to chemical agents, the samples shall not bear any traces of chemical staining likely to cause a variation of flux diffusion, whose mean variation

       measured on the three samples according to the procedure described in Appendix 2 to this Annex