9. The expert from the Kingdom of the Netherlands introduced informal document GRSP-76-18-Rev.1 to allow the use of talcum as an alternative to dry quartz for the dust resistance test. The expert from CLEPA requested a study reservation. The expert from the Russian Federation noted that the proposed alternative did not provide evidence that it was safer. GRSP agreed to distribute informal document GRSP-76-18-Rev.1 with an official symbol at its May 2025 session.

12. The expert from the Kingdom of the Netherlands introduced informal document GRSP-77-33-Rev.1, which superseded ECE/TRANS/WP.29/GRSP/2025/3. He explained that the final drafting of the amendment kept dry quartz as the requirement in the test description and then offered talcum as an alternative way of fulfilling this requirement. He also clarified that the relative softness of talcum did not lower the stringency of the test, as this test was measuring dust intrusion, not durability and that it should be up to type approval authorities, to decide which substance to use in the test. The expert from CLEPA supported the proposal and announced that they were carrying out tests to assess the difference between the two substances and would bring the results to the next GRSP session.