4.5.1 Test pieces shall be exposed dependent upon their class to 168 h ± 1 h at Temperature B per Table 2.
An air circulating oven with a temperature tolerance ±3 °C shall be used.
4.5.2 Wash weathered specimens prior to making measurements and observations. Wash with scrubbing
action using a sponge that is saturated with a solution consisting of soap and deionized water at
+22 °C ± 3 °C.