Document ID: chunk:federal_register_of_legislation:F2015C00542:reg:254:p5
Version: federal_register_of_legislation:F2015C00542
Segment Type: reg
Provision Reference: reg 254 (pt 5/18)
Character Range: 111564–114483

Measure the light scattered by the abraded track at a minimum of four equally-spaced points along the track in accordance with the formula above. Average the results for each test piece. In lieu of the four measurements, an average value may be obtained by rotating the piece uniformly at 3 rev/sec or more.

              4.5. The abrasion test will be carried out only at the discretion of the laboratory conducting the test with due regard to the information already at its disposal.

               Except for glass-plastics materials, changes in the interlayer or materials thickness will not normally necessitate further testing.

              4.6. Indices of difficulty of the secondary characteristics

               No secondary characteristics are involved.

              5. Test of resistance to high temperature

              5.1. Procedure

               Heat to 100 °C three samples or three square test pieces of at least
              300 mm x 300 mm which have been cut by the laboratory from three windscreens or three glass panes as the case may be, one edge of which corresponds to the upper edge of the glazing. Maintain this temperature for a period of two hours, then allow the samples or test pieces to cool to room temperature. If the safety glazing has both external surfaces of inorganic material, the test may be carried out by immersing the sample vertically in boiling water for the specified period of time, care being taken to avoid undue thermal shock. If samples are cut from windscreens, one edge of each such sample shall be part of an edge of the windscreen.

              5.2. Indices of difficulty of the secondary characteristics

                Colourless Tinted

               Colouring of the interlayer 1 2

               The other secondary characteristics are not involved.

              5.3. Interpretation of results

              5.3.1. The test for resistance to high temperature shall be considered to give a positive result if bubbles or other defects are not formed more than 15 mm from an uncut edge or 25 mm from a cut edge of the test piece or sample or more than 10 mm away of any cracks which may occur during the test.

              5.3.2. A set of test pieces or samples submitted for approval shall be considered satisfactory from the point of view of the test for resistance to high temperature if all the tests have given a satisfactory result.

              6. Resistance-to-radiation test

              6.1 Test method

              6.1.1. Apparatus

              6.1.1.1. Radiation source consisting of a medium-pressure mercury-vapour arc lamp with a tubular quartz bulb of ozone-free type; the bulb axis shall be vertical. The nominal dimensions of the lamp shall be 360 mm in length by 9.5 mm in diameter. The arc length shall be 300 mm ± 4 mm. The lamp shall be operated at 750 W ± 50 W.

               Any other source of radiation