ADR special provision 623
Sulphur trioxide (UN 1829) must be inhibited, except ≥ 99.95 % pure in tanks kept at ≥ 32.5 °C, with a document statement.
UN 1829 sulphur trioxide has to be inhibited. Product of 99.95 % purity or more may go uninhibited in tanks if held at 32.5 °C or above. In that case the transport document must state that it is carried under a minimum product temperature of 32.5 °C.
| Value | Applies when |
|---|---|
| 99.95 % purity | minimum purity for uninhibited tank carriage |
| 32.5 °C | minimum product temperature for uninhibited tank carriage |
| documents | Transport document statement of carriage under a minimum product temperature of 32.5 °C (uninhibited tank carriage only). |
|---|
Carried by 1 Table A entry
Source: ADR 2025 (ECE/TRANS/352), Volume I, section 3.3.1, special provision 623, page 647.
Paraphrase in FreightUtils' own words, not the official text. Not yet reviewed.
ADR 2027 amendments (accepted, applying from 1 January 2027) are not yet reflected on this page.