But can UN1500 be used for a solution of Sodium Nitrite?
ADR 3.1.3 states that:
3.1.3 Mixtures and solutions containing one dangerous substance
3.1.3.1 A mixture or solution containing a dangerous substance identified by name in the Dangerous Goods List and one or more substances not subject to these Regulations shall be treated according to the requirements given for the dangerous substance provided that the packaging is appropriate to the physical state of the mixture or solution, unless:
(a) The mixture or solution is specifically identified by name in these Regulations; or
(b) The entry in these Regulations specifically indicates that it applies only to the pure substance; or
(c) The hazard class, physical state or packing group of the solution or mixture is different from that of the dangerous substance; or
(d) There is significant change in the measures to be taken in emergencies.
With regards to (c) and (d), the physical state obviously changes as Sodium Nitrite is a solid whereas a solution is a liquid, the emergency procedures would change as well as you’d be dealing with a mobile liquid rather than a solid.
So would UN 3219 not be the most appropriate?