UN 1835 Tetramethylammonium hydroxide, aqueous solution, conc. <= 2.5 % UN Rec. 23rd rev. ed. (Detailinfo)

If the chemical or physical properties of a substance covered by this description are such that when tested it does not meet the established defining criteria for the class or division listed in column (3), or any other class or division, it is not subject to these Regulations.

This entry applies only to aqueous solutions comprised of water, tetramethylammonium hydroxide (TMAH), and no more than 1 % of other constituents. Other formulations containing tetramethylammonium hydroxide must be assigned to an appropriate generic or N.O.S. entry (e.g., UN 2927, TOXIC LIQUID, CORROSIVE, ORGANIC, N.O.S., etc.), except as follows: (a) Other formulations containing a surfactant in a concentration > 1 % and with not less than 8.75 % tetramethylammonium hydroxide must be assigned to UN 2927, TOXIC LIQUID, CORROSIVE, ORGANIC, N.O.S., PG I; and (b) Other formulations containing a surfactant in a concentration > 1 % and with more than 2.38 % but less than 8.75 % tetramethylammonium hydroxide must be assigned to UN 2927, TOXIC LIQUID, CORROSIVE, ORGANIC, N.O.S., PG II.

The provisions of chapter 3.2 from the twenty-second revised edition of the Recommendations on the Transport of Dangerous Goods, Model Regulations may continue to be applied until 31 December 2026.