Skull and Cross Bones
Inhalation Hazards – TDG Marking & Documentation

Man Wearing Respirator

Changes in Special Provision 23

One aspect of the International Harmonization amendment (SOR/2017-137) of the Canadian Transportation of Dangerous Goods Regulations (TDGR) that did not receive a lot of attention is the change in Special Provision 23. This special provision (SP) deals with the assignment of markings on containers and descriptions on shipping documents for entries related to goods which exhibit inhalation toxicity. Although the basic concept for classification remains the same- i.e. gases in Class 2.3 and Class 6.1 with associated inhalation toxicity. The majority of the latter are in PG I, but there are several PG II entries invoking SP23).

Marking – Keep It Simple?

A significant difference is the change in wording applied to means of containment (MoC). Following the transition period, markings required under SP23 must read “inhalation hazard” for all entries except UN 1005 (anhydrous ammonia). This eliminates the previous options of either “toxic by inhalation” or “toxic-inhalation hazard” (TBI or TIH).

UN1005 retains the previous wording “Anhydrous Ammonia, Inhalation Hazard” when the option of using the ammonia placard (rather than Class 2.3) is chosen. However small MoC of UN1005 will use the standard Class 2.3 label and “inhalation hazard” wording.

Size Matters

Letter Size
The new SP23 simplifies things somewhat by referencing Continue Reading…