A placard is a dangerous goods safety mark that is displayed on a large means of containment (MOC). It is used to identify dangerous goods and to show the nature of the danger they pose.
There is so much confusion around when placards are required in Canada so we have put together some Q&As to help understand Transport Canada’s requirements.
What safety marks are required on a Small Means of Containment (capacity 450L or less)?
Which labels or placard must be displayed depends on the classification of the dangerous good. The requirements for the display of the dangerous goods safety marks also depend on:
Labels and placards are diamond shaped (also referred to as “square on point”) and must be displayed as illustrated below.
Figure 1: Label and placard (Image from Transport Canada)
When and How Must a Placard be Displayed?
As per Section 4.15 of the TDG Regulations, the primary class placard for each dangerous good contained in a large means of containment must be displayed on each side and on each end of the large means of containment. Each placard only needs to be displayed once on each side and each end regardless of how many products in the large means of containment correspond to that class (primary or subsidiary).
For example, if a vehicle is transporting UN1833, SULFUROUS ACID (Class 8) and UN1836, THIONYL CHLORIDE (Class 8), only one Class 8, placard is required to be displayed on each side and on each end of the vehicle.
A subsidiary class placard is required to be displayed on a large means of containment for dangerous goods that requires an emergency response assistance plan (ERAP) if they are included in one of the following subsidiary class:
The subsidiary class placard must be displayed next to the primary class placard on each side and on each end of the large means of containment:
Note: A placard must NOT be displayed at a 45-degree angle on a truck frame or a supporting frame for the means of containment; it must remain as a square on point. Otherwise, it does not comply with the TDG Regulations.
Do Other Safety Marks Need to be Displayed on a Large Means of Containment?
Aside from placards, a large means of containment must also display the UN number of the dangerous goods if:
The UN number must appear on the placard or on a rectangular orange panel, without the prefix “UN”, next to the placard (see image below).
When Can I Use the DANGER Placard?
The DANGER placard is optional. It may be displayed on a large means of containment instead of any other placard required by Section 4.15.1 of the TDG Regulations if two conditions are met:
However, there are exceptions to this rule. The DANGER placard cannot be displayed on a large means of containment if:
Note: If a road or railway vehicle to be transported by vessel contains a flammable gas, the flammable gas placard (Class 2.1) must be displayed on the road or railway vehicle.
Can I Voluntarily Display Placards for Any Quantity of Dangerous Goods?
Despite the fact that a placarding exemption may be used, a person may voluntarily display a placard for any quantity of dangerous goods when they are transported in a road or railway vehicle if certain provisions of Part 4 are met. These provisions include:
All of the above provisions must be met in order to voluntarily display a placard.
SOURCE: https://tc.canada.ca/en/dangerous-goods/dangerous-goods-safety-marks