DANGEROUS GOODS regulations refer to hazards during transport (in public places). In such circumstances, different criteria may be important compared to when handling/working with hazardous substances; in these cases, the criteria are set out in HAZARDOUS SUBSTANCE regulations.
When transporting 617P37 and 617PG37, the “most dangerous” aspect is the auto-ignitability or, in this case, the self-accelerating decomposition of peroxide in both substances, which can be triggered for some peroxides due to excessive temperatures in the lorry, for example. With respect to transport, therefore, it does not matter in the first instance whether the products contain substances of very high concern (SVHC) or not. Both contain peroxides; therefore, UN 3106 (organic peroxide type D) applies to both products.
From the perspective of HAZARDOUS SUBSTANCES law, there are certainly material differences between the two products. These are stated in documentation such as the safety data sheet in the form of hazard statements (H statements). The H statements come from hazardous substance law, which governs the handling of / work with the hazardous substance. Although heating and potential heating that would represent a fire hazard is important here (e.g. during storage) and is also addressed in the safety data sheet, the carcinogenic or toxic to reproduction property is deemed to be “more important” when handling the substance according to hazardous substances law, and differences in the H statements can also be found when 617P37 and 617PG37 are compared.
Against this backdrop, the UN number cannot be changed. This is also determined based on a classification procedure, in which there is no leeway.