Converting Transport classifications to CLP
Many transport classifications are directly equivalent to CLP classifications, and a series of tables showing these equivalent classifications is given in GHS, in Annex 1. A copy is available here for reference: Annex 1 to GHS Rev 7 with transport equivalents.
In some cases, a Transport classification may have more than one CLP hazard, and this usually refers to differences in Packing Group. In the ECHA guidance on the Application of CLP Criteria, Table VII.1 is a translation table which does include Packing Group information, and a copy of this table is available for reference: ECHA-Application-of-CLP-Criteria-Guidance-Table-VII.1.
Note that these read-across tables do not always mean that a Transport-classified product can be translated completely to GHS or CLP, because quite a few of the lower-level health hazards in CLP do not appear in Transport, and Transport does not include any of the EUH statements.
You should also be aware that where a substance has a proper shipping name which does not include “NOS”, “not otherwise specified”, it may be on the Dangerous Goods List and therefore have the transport equivalent of a harmonised classification, meaning that it may not have the same CLP classification as for Transport.
Transport is also concerned with non-chemical hazards, and includes biological hazards and radioactivity hazards, which are both outside the scope of CLP.
Even though Transport and GHS are supposed to be (mostly) harmonised with each other, there are a couple of areas where the symbols (or pictograms) may not agree with each other: Non-equivalent hazards in CLP and Transport systems .
All of this means that if you are going to use Transport information for CLP classification purposes, it helps to understand the Transport classification system, or have access to a Dangerous Goods Safety Advisor, who can help with interpreting the Transport classification.