Transportation of Dangerous Substances in Passenger or Recreational Vehicle

​​​​The transportation of propane cylinders, fuel cans, chlorine for swimming pools, or oxygen for medical emergencies must comply with the Transportation of Dangerous Substances Regulation. This regulation applies to all road users to ensure that dangerous substances are transported safely, minimizing the risks for the population, the environment and property.

Commonly used dangerous substances

Dangerous substances are classified based on the type of risk they pose and their properties. Some of the most commonly used dangerous substances are:

  • propane, butane, acetylene, and other flammable gases
  • gasoline, diesel fuel, kerosene, methanol and other flammable liquids
  • air, nitrogen, helium and other non-flammable gases
  • oxygen and other oxidizing gases
  • car batteries, chlorine for swimming pools, fireworks, cleaners, certain types of glues, and paint remover.

There are more than 3,500 dangerous substances. A complete list of these substances is available in the Transportation of Dangerous Goods Regulations.

How to transport dangerous substances

For your safety and the safety of others, it is important to follow a few simple rules:

  • The container used must be approved and standardized specifically for their content. For example, a gallon of windshield washer fluid cannot be used to carry gasoline.
  • Containers must always be immobilized, whether they are full or not.
  • The weight of each container must not exceed 30 kilograms (66 pounds). If more than 150 kilograms (330 pounds) of dangerous substances are to be transported in a passenger or recreational vehicle, refer to the Transportation of Dangerous Substances Guide (2,84 MB) for the requirements.


  • Flammable gas (e.g. propane) cylinder capacity must not exceed 46 litres, which is roughly the equivalent of a 40-pound propane cylinder. Refer to the Transportation of Dangerous Substances Guide (2,84 MB) for the requirements on transportation of flammable gas cylinders with a capacity of more than 46 litres.


Also, when transporting propane:

  • Cylinders, whether they are full or empty, must be firmly secured as to be completely immobilized.
  • They must be secured in a vertical position in a space with exterior ventilation, namely:
    • in the trunk, left partially open
    • in the passenger compartment with a half-open window.
  • If a travel trailer or tent trailer is pulled by the vehicle, it is recommended to place cylinders in the front part of the trailer.
  • If the cylinders are placed on the outside of a motor vehicle, they must be installed at the rear along the width of the bumper and be protected by materials as resistant as the bumper is.


Vertical position


Exterior ventilation


Propane cylinders must never be installed:

  • on the roof or a door
  • in front of the front axle of a motorized vehicle
  • in a manner so that they stick out from either side of the vehicle

Litres or pounds?

The capacity of propane cylinders sold in Québec is indicated in pounds, whereas it is indicated in litres in transportation standards. For example, propane cylinders commonly used for barbecue grills have a 20-pound capacity, which is roughly equivalent to 22 litres.

Propane cylinder capacity in litres and in pounds

Cylinder in poundsVolume (water capacity) in litresEmpty cylinder weight in kilogramsFull cylinder weight in kilograms

Tunnels and bridge-tunnels

Additional rules on the transportation of dangerous substances apply in the following tunnels and bridge-tunnels.

  • Louis-Hippolyte-La Fontaine, Ville-Marie and Viger in Montréal
  • Joseph-Samson in the city of Québec
  • Melocheville in Beauharnois

Dangerous substances allowed or prohibited in tunnels

Transported substancesAllowedProhibited
Acetylene, butane, propane or other flammable gases​2 cylinders, each with a capacity of 46 litres or lessMore than 2 cylinders (any capacity)

1 cylinder with a capacity of more than 46 litres​
​Oxygen2 cylinders, each with a capacity of 46 litres or lessMore than 2 cylinders (any capacity)

1 cylinder with a capacity of more than 46 litres​
Gasoline, diesel fuel, methanol, solvents or other flammable liquidsA container or containers with a maximum total capacity of 30 litres​A container or containers with a maximum total capacity of more than 30 litres​
  • It is recommended to turn off the valve of the propane cylinder before entering a regulated tunnel
  • These prohibitions do not apply to fuel (gasoline, diesel, propane or methane) used for the propulsion of a vehicle and contained in one or more tanks designed for that purpose by the vehicle manufacturer or compliant with the Regulation respecting safety standards for road vehicles.

New signs near tunnels

New signs were installed near tunnels to remind motorists of the quantities allowed for two of the most commonly used dangerous substances, namely gasoline and propane. You can therefore change your route before it is too late to do so.


The Société des traversiers du Québec’s Website sets out the restrictions regarding the transportation of certain substances on its ferries.

Safety tips

Precautions need to be taken before and during the transportation of dangerous substances.

Prior to departure

  • Check that containers are secured so that they are completely immobilized
  • Ensure that the quantity transported is compliant with standards, and the substance is carried in the appropriate container

During transportation

  • Drive with extra caution
  • Adapt your driving to road conditions
  • Observe speed limits
  • Comply with braking distances
  • Refrain from smoking