2.16.2.: Classification criteria A substance or a mixture which is corrosive to metals is classified in a single category for this class, using the test in Part III, sub-section 37.4 of the ►M4  UN RTDG ◄ , Manual of Tests and Criteria, in accordance with Table 2.16.1:

Table 2.16.1

Criteria for substances and mixtures corrosive to metals




Corrosion rate on either steel or aluminium surfaces exceeding 6,25 mm per year at a test temperature of 55 °C when tested on both materials.


Where an initial test on either steel or aluminium indicates the substance or mixture being tested is corrosive the follow up test on the other metal is not required.