Special provision 603
ADR 2025 — special provision (SP) 603, Chapter 3.3.
Anhydrous hydrogen cyanide not meeting the description for UN No. 1051 or UN No. 1614 is not to be accepted for carriage. Hydrogen cyanide (hydrocyanic acid) containing less than 3 % water is stable, if the pH-value is 2.5 ± 0.5 and the liquid is clear and colourless.