TDG – Unit 4
Dangerous Goods Safety Marks
The Act and Regulations establish when it is necessary to display safety marks on dangerous goods in
transport. Safety marks include labels, placards, orange panels, signs, marine pollutant marks, numbers,
letters, abbreviations and words used to identify dangerous goods and show the nature of the danger they
pose.
Safety marks provide a quick identification of dangerous goods. This is particularly important in the event of
an emergency situation such as an accident or an accidental release of dangerous goods from a means of
containment.
Dangerous Goods Safety Marks
We have already looked at the 9 Classes of dangerous goods in the “Classification” section of this program.
As was saw, each of these Classes of dangerous goods was represented by an example of a “safety mark”.
We will now quickly review these classes:
CLASS 1 - Explosives
CLASS 2 – GASES
]
CLASS 3 – FLAMMABLE LIQUIDS
CLASS 4 – FLAMMABLE SOLIDS/ SPONTANEOUSLY COMBUSTIVE/ WATER REACTIVE
SUBSTANCES)
CLASS 5 – OXIDIZING SUBSTANCES & ORGANIC PEROXIDES
CLASS 6 – INFECTIOUS SUBSTANCES
CLASS 7 – RADIOACTIVE MATERIALS
CLASS 8 – CORROSIVES
CLASS 9 - MISCELLANEOUS PRODUCTS, SUBSTANCES OR ORGANISMS
OTHER
We will now take a look at some of the “other” safety marks involved in the transportation of dangerous
goods. All of these symbols and markings can be found in the TDG Regulations.
Other Safety Marks - Elevated Temperature Sign
The elevated temperature sign must be displayed for dangerous goods
that are in transport in a large means of containment and that are
classified as “Elevated Temperature”.
The elevated temperature sign must be displayed on each side and each
end of the large means of containment next to each primary class
placard for the dangerous goods, or, if there is a subsidiary class placard, next to the
subsidiary class placard.
Fumigation Sign
When dangerous goods are used to fumigate a large means of containment, a fumigation sign must be
displayed next to or at each entryway into a large means of containment through which a person can enter.
The consignor must ensure that the fumigation sign is displayed by the person in charge of the fumigation
process. The sign must also display the name of the fumigant and the date and time the fumigant was
applied.
Other Safety Marks - Marine Pollutant
The marine pollutant mark must be displayed for dangerous goods that are marine pollutants in transport by
ship.
The marine pollutant safety mark is not required to be displayed when marine pollutants are on board a road
vehicle or railway vehicle on a roll-on roll-off ship. The mark is also not required when marine pollutants are
contained in a small means of containment and are in limited quantity.
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5 L for a liquid marine pollutant
5 kg for a solid marine pollutant
500 mL for a liquid severe marine pollutant
500 g for a solid severe marine pollutant,
Other Safety Marks - Certification
A certification safety mark is required to be displayed by the manufacturer of the means of containment. This
is done to illustrate compliance with the safety standard.
Other Safety Marks - Foreign Shipments
In specific cases, the TDG Regulations allow for the use
of safety marks in accordance with other regulations
Air shipments - ICAO Technical Instructions
International marine shipments - IMDG Code
US to Canada shipments (road and rail) - CFR (Code of Federal Regulations) 49
Dangerous Goods Safety Marks
Safety marks are a valuable awareness tool for a wide
range of people involved in the transportation of
dangerous goods – for example: truck drivers, train
crews, loading dock workers, aircraft loading
personnel, reception personnel at a lab or hospital,
and emergency personnel.
Responsibility for Dangerous Goods Safety Marking
Section 4.1 of the Regulations clearly defines when Safety
Marks are required. This section states, “A person must not
offer for transport, transport or import a means of
containment that contains dangerous goods unless each
dangerous goods safety mark required by this Part and
illustrated in the appendix to this Part, or illustrated in
Chapter 5.2 or 5.3 of the UN Recommendations, is
displayed on it in accordance with this Part.”
Misleading Dangerous Goods Safety Marks
A person must not display a prescribed safety mark on a means
of containment, a means of transport, or at a facility, if the mark
is misleading as to the presence of danger or the nature of any
danger. Effort must be made to ensure that the safety marks
adequately reflect the danger at all times during “transport”.
Safety Marks - Consignor Responsibilities
Before importing dangerous goods, or allowing a carrier in Canada to
take possession of dangerous goods for transport, a consignor must:
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Display or ensure the display of the required safety marks
on each small means of containment that contain dangerous
goods.
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Display or ensure the display of the required safety marks
on a large means of containment that contain dangerous
goods.
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Provide the carrier with the safety marks for the dangerous goods that the consignor is offering for
transport or importing and that are to be transported in a large means of containment.
Safety Marks – Consignor Responsibilities
The consignor is not required to provide the safety marks if
they are already displayed on a large means of
containment. This is also the case if the safety marks are
not the correct ones to display because of the presence of
other dangerous goods in a large means of containment. A
“large means of containment” is a means of containment
that has a cargo capacity greater than 450 L. (truck,
tankcar, etc.). Means of containment, both large and small,
will be further reviewed later in this section of the course.
When the consignor provides the large means of
containment, they are responsible for displaying the safety marks. When the carrier provides the large
means of containment, the consignor must provide the carrier with the appropriate safety marks.
Safety Marks - Carrier Responsibilities
A “carrier” is the person who, whether or not for hire or reward, has
possession of dangerous goods while they are in transport. With
respect to safety marking a carrier of dangerous goods must:
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Ensure that the required safety marks remain displayed on a
“small means of containment” (cargo capacity less than or
equal to 450 L.) while the dangerous goods are in transport;
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Display the required safety marks on the large means of
containment, unless they are already displayed on it, and
ensure that they remain displayed while the dangerous goods
are in transport;
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Provide and display, or remove, the safety marks if the requirements for marking change while the
dangerous goods are in transport.
Visibility, Legibility and Colour
Dangerous goods safety marks must be visible, legible and
displayed against a background of contrasting colour. They
must also be made of durable and weather-resistant material
that will withstand the conditions to which they may be
exposed without substantial detachment or deterioration of
their colour, symbols, letters, text or numbers. Safety marks
must also be displayed in the colours specified in the appendix
to Part 4.
Removal of Dangerous Goods Safety Marks
Dangerous goods safety marks must remain displayed on a means of
containment until its contents have been neutralized or the means of
containment have been unloaded, unpacked, cleaned or purged. This is to
ensure that there is no longer any danger in the means of containment.
The person who neutralizes the contents of the means of containment, or who
unloads, unpacks, cleans or purges it, must cover or remove the dangerous
goods safety marks when there is no longer a danger present in the means of
containment.
Means of Containment
To better understand the application and
requirements for safety marks, we will now take
a look at the “means of containment” required by
the TDG Act and Regulations. This part of the
course will identify the types of “means of
containment” used for transporting dangerous
goods, and, describe the procedure in selecting
and safety marking a means of containment.
The requirements for “means of containment” are in the form of published standards that
are adopted by reference in the TDG Regulations. The standards relate to the design,
manufacture, marking and use of various types of containers. The TDG Directorate
administers registration programs for facilities or persons that manufacture and maintain
means of containment in accordance with these standards.
Means of Containment
The Transportation of Dangerous Goods (TDG) Act and
Regulations, along with a number of applicable standards,
require that dangerous goods be transported in a safe
means of containment. A “safe means of containment”
prevents the release of dangerous goods that could
constitute a danger to life, health, property or the
environment. The TDG Regulations often refer to other
regulations or standards for the manufacturing and the
selection and use of means of containment for dangerous
goods.
Regulations and standards may be specific to a class of dangerous goods, means of containment or mode
of transport. Most means of containment standards in Canada are based on the UN Recommendations. UN
standardized means of containment are internationally recognized and can be used anywhere in the world
and by any mode of transport. Some means of containment standards are specific to Canada, as no
international standards exist. Cylinders, tubes, highway tanks, some portable tanks and tank car tanks are
examples of these “TC” standardized means of containment. These means of containment can be used in
Canada and sometimes in the United States if the specification to which they are manufactured corresponds
to American standards (DOT specification).
Mode of Transport / Destination
There may be additional packaging requirements based on the mode
of transport and/or destination. Refer to the appropriate regulation for
more information.
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The International Civil Aviation Organization Technical Instructions (ICAO Technical Instructions)
must be consulted for air transport requirements.
The International Maritime Dangerous Goods Code (IMDG Code) must be consulted for
segregation requirements and international marine transport.
The Code of Federal Regulations, Title 49, (CFR 49), must be consulted for road and rail
shipments to the United States.
Certification Safety Marks on a Means of Containment
All standardized means of containment bear certification
safety marks to indicate that they were manufactured in
compliance with a standard. A certification safety mark is
any design, symbol, device, letter, word, number or
abbreviation that is displayed on a means of containment,
or means of transport, to indicate compliance with a safety
standard.
To remain in standard, some means of containment must
be periodically inspected and tested and marked at intervals
specified by the standard or regulation. These marks
describe what, when and by whom the inspections and tests
were performed. All certification safety marks must be
durable, visible, legible and easily accessible for inspection.
The Types of “Means of Containment”
The TDG Act and Regulations define two types
of “means of containment”.
1. Small means of containment
2. Large means of containment
Small Means of Containment
Small means of containment are containers with a
water capacity of 450L or less. They may be
drums, jerricans, boxes, pails, bags, barrels,
cylinders or intermediate bulk containers.
Large Means of Containment
Large means of containment are containers with a water capacity greater than 450L. They may be highway
tanks, tank cars, intermediate bulk containers, portable tanks or tubes.
“Large means of containment” can be tote tanks, intermodal tanks, portable tanks,
intermediate bulk containers (IBC), freight containers, portable tanks, tubes, road and rail
vehicles. Once again, a large means of containment means a containment that has a cargo
capacity greater than 450 L.
Selecting a Means of Containment :
When selecting the appropriate means of containment, a
person who offers for transport dangerous goods must
determine:
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the class of dangerous good(s);
the type and size of the means of containment;
the mode of transport; and;
the destination of the dangerous good(s).
Safety Marks on a Means of Containment
Now that we have a basic understanding of the means of
containment involved in the transportation of dangerous
goods, we can now combine them with our study of safety
marks.
Labels and Placards
Labels and placards are diamond shaped and must be displayed as illustrated below. They are usually
identical (except for the size) and they communicate by colour, number and symbol the degree and nature of
the hazard of dangerous goods. The specific labels and placard symbols will be examined in detail at the
end of this section.
Labels and Placards - Dimensions
Because of the size or irregular shape of certain means of containment, the
TDG Regulations allow for the reduction of labels (30 mm) and placards
(100 mm). When this occurs, all means of identification on the safety mark
must also be reduced. Under the Clear Language Regulations, Class 7
(Radioactive labels) may not be reduced in size and must be displayed on
two opposite sides of a small means of containment.
Safety Marks on a Small Means of Containment: Labels
Unless otherwise specified in the regulations, labels must be applied to every small container, package and
cylinder that contains dangerous goods and is to be offered for transport. One label must be displayed on a
small means of containment for the primary class and one for each subsidiary class for each dangerous
good in transport.
Labeling – Special Considerations
A label is not required to be displayed on a small means of containment that is inside another small means
of containment if the other small means of containment has a label displayed on it, and, it is not opened
during loading or unloading or while in transport.
Labeling – Special Considerations
If the dangerous goods are included in Class 7, Radioactive Materials, two labels for the primary class must
be displayed on the small means of containment.
In addition, the oxidizing gas label must be displayed on all small means of containment for the following
dangerous goods:
UN1072, OXYGEN, COMPRESSED;
UN1073, OXYGEN, REFRIGERATED LIQUID;
UN3156, COMPRESSED GAS, OXIDIZING, N.O.S.; and
UN3157, LIQUEFIED GAS, OXIDIZING, N.O.S.
Labeling Requirements
When a label is required to be displayed, it
must be displayed:
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on any side of the outer surface
of a small means of containment other than the side on which it is intended to rest or to be stacked
during transport (top and bottom);
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on the shoulder of a cylinder containing dangerous goods; or
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in the case of a label for dangerous goods included in Class 7, Radioactive Materials, on two
opposite sides of the outer surface of a small means of containment, other than the side on which it
is intended to rest or to be stacked during transport.
Reduced Labels
A label with sides that are reduced to 30 mm in length may be displayed
on a tag that is securely attached to a small means of containment.
Labeling Requirements - Small Means
of Containment
The shipping name, technical
name (if any) and UN number
must also be displayed on small
means of containment. The UN
number may appear on or next to
the label.
Placard Requirements - Large Means of Containment
All dangerous goods for transport must be
properly marked before loading or packing of a
large means of containment. A large means of
containment must have the appropriate safety
marks displayed on it that will be required when
the loading or packing is complete.
Placard
Requirements Large Means of
Containment
Placards and UN numbers must be displayed on each side and end of a large means of containment
(greater than 450 L), other than a ship or an aircraft, if the dangerous goods:
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Have a total gross mass greater than 500 kg (UN number is only required when the quantity
exceeds 4000 kg);
Are in a quantity or concentration that require an emergency response assistance plan (ERAP); or;
Are a liquid or a gas in direct contact with the means of containment.
Placards - UN Number
The UN number must appear on the placard or on a rectangular orange panel next to the placard.
Safety Marks on a Large Means of Containment:
Placards and UN Numbers
A mixed load of dangerous goods of different UN
numbers (none requiring an Emergency Response
Assistance Plan) may be identified by a
DANGER placard instead of the placard required
for those dangerous goods.
Safety Marks on a Large Means of Containment:
Placards and UN Numbers
A placard and UN number must be displayed on a large
means of containment, other than a ship or an aircraft, if:
(a) the dangerous goods:
 are in a quantity or concentration for which an emergency
response assistance plan is required,
 are included in Class 7, Radioactive Materials, for which a
Category III –yellow label is required,
 are a liquid or gas in direct contact with a large means of
containment, or
 have a total gross mass greater than 500 kg; or
(b) the large means of containment contains a consignment on which a placard is required to be displayed
but that placard is not visible from outside the large means of containment.
Placards and UN Numbers - Display
When determining the display of placards and UN numbers the following table should be consulted.
Familiarize yourself with this table – it is available in Part 4 of the regulations or in the “Links” section of this
website under “Resource Materials”.
* Emergency Response Assistance Plans will be detailed later in the course
Safety Marks on a Large Means of Containment:
Placards
The placard must be displayed on each side and
each end of a large means of containment. A
subsidiary class placard, without the class
number in the bottom corner, must be displayed
on each side and each end of a large means of
containment for dangerous goods for which an
emergency response assistance plan.
General Options for Placards and UN Numbers
Despite the requirement for the display of
primary class placards, when two dangerous
goods have different UN numbers but are
identified by the same primary class placard, that
placard needs to be displayed only once on each
side and each end of a large means of
containment.
Placard Options for Class 1, Explosives
A placard is not required to be displayed for explosives that are included in:
 Class 1.4 and in a quantity less than or equal to 1 000 kg; or
 Class 1.4S in any quantity.
Only the placard for the explosives with the lowest division number is required
to be displayed for explosives that are included in more than one division in a
large means of containment, except in the following cases:
 when explosives included in Class 1.2 and Class 1.5 are transported
together, the placard for Class 1.1 must be displayed; and
 when explosives included in Class 1.4 and Class 1.5 are transported together, the placard for Class 1.5
must be displayed.
Despite the requirement in section 4.15 for the display of a UN number, a UN number is not required to be
displayed for Class 1, Explosives.
Placard Options for Class 2, Gases
A mixed load of different classes of gases transported by road, solely on land, may be identified by a
DANGER placard and a primary class placard for the most dangerous gas according to the following
decreasing order of danger: 1. toxic gas, 2. flammable gas, 3. oxidizing gas, 4. any other gas.
In addition to the requirements for placards and UN numbers in section 4.15, when one of the gases on a
road vehicle or railway vehicle that is to be transported by ship is included in Class 2.1, Flammable Gas, the
flammable gas placard must be displayed.
Placarding - Oxidizing Gases
When dangerous goods are oxidizing gases, the oxidizing gas placard may be displayed for the following
dangerous goods instead of the placards:
(a) UN1072, OXYGEN, COMPRESSED;
(b) UN1073, OXYGEN, REFRIGERATED LIQUID;
(c) UN3156, COMPRESSED GAS, OXIDIZING, N.O.S.; and
(d) UN3157, LIQUEFIED GAS, OXIDIZING, N.O.S.
Safety Marks on a Compartmentalized Large Means of
Containment
When dangerous goods included in different primary
classes are transported in different compartments of a
compartmentalized large means of containment:
 the primary class placard and the UN number for the
dangerous goods in each compartment must be displayed
on each side of that compartment;
 the primary class placards and UN numbers for all of the
dangerous goods in the compartments must be displayed
on each end of the compartmentalized large means of
containment.
Safety Marks on a Compartmentalized Large Means of Containment(cont.)
When all compartments in a compartmentalized large means of containment contain dangerous goods
included in the same primary class:
 the primary class placard must be displayed on each side and on each end of the compartmentalized
large means of containment; and
 the UN number must be displayed on each side of the compartment and on each end of the
compartmentalized large means of containment. If all the dangerous goods are included in Class 3,
Flammable Liquids, only the UN number of the dangerous goods with the lowest flash point need be
displayed on each side and on each end of the compartmentalized large means of containment.
Clear Language Regulations
Summary of Changes in Safety Marks for Small Means of Containment
Labels
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Labels must be displayed for primary class and all subsidiary classes.
Subsidiary class labels must display class numbers and do not need to be placed in a subsidiary
location.
There is now only one label for Class 9.
Class 2.4 and Class 6.1 Packing Group III labels no longer used.
Radioactive labels (Class 7) may not be reduced in size, and must be displayed on two opposite
sides of a small means of containment.
The UN number may be displayed either on or beside the primary class label.
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Control or emergency temperatures do not need to be displayed.
Use of fumigation label has changed.
Summary of Changes in Safety Marks for Large
Means of Containment
A placard with the UN number is required for
dangerous goods that:
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Are a liquid or gas in "direct contact"
with the large means of containment.
Require an Emergency Response Assistance Plan (ERAP),
Have the same UN number and are in a quantity greater than 4,000 kg and offered for
transport by one consignor.
The DANGER placard may be used for mixed loads of dangerous goods that do not
require an ERAP if the gross mass exceeds 500 kg.
General
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Elevated Temperature Liquid - has been added.
Labels no longer used — EMPTY (optional), Attention PCB, Package Orientation ("this side up").
Oxygen Depletion sign is no longer used.
There is no longer a requirement for placards to be placed on coupling devices for loading and
unloading dangerous goods.
There is no longer a requirement to use UN number on orange panel for specific Class 2.3 Toxic
Gases.
There is no longer a requirement for placards to be retro-reflective.
Proceed to test
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