Special provision 523
ADR 2025 — special provision (SP) 523, Chapter 3.3.
UN No. 1382 anhydrous potassium sulphide and UN No. 1385 anhydrous sodium sulphide and their hydrates with less than 30 % water of crystallization, and UN No. 2318 sodium hydrosulphide with less than 25 % water of crystallization are substances of Class 4.2.