Is DEF Required in Canada?

If you operate diesel-powered vehicles in Canada, you’ve likely encountered DEF, an important component for reducing harmful emissions. But why is it required? The answer lies in emissions regulations. Canada enforces strict environmental laws, primarily through Environment and Climate Change Canada (ECCC) and Transport Canada, aimed at lowering nitrogen oxide (NOx) emissions from diesel engines. NOx is a major contributor to air pollution and smog, which is why the Selective Catalytic Reduction (SCR) system—which requires Diesel Exhaust Fluid (DEF)—has become standard in modern diesel engines.

DEF is a non-toxic urea and deionized water solution that helps break down NOx emissions into harmless nitrogen and water vapor. Without it, heavy-duty trucks, buses, and off-road equipment would not meet Canadian emissions standards.

What Does Canadian Law Say About DEF?

The use of DEF in Canada is legally required under the Canadian Environmental Protection Act (CEPA) 1999, which gives the government authority to regulate emissions from on-road and off-road engines. The On-Road Vehicle and Engine Emission Regulations align closely with the U.S. Environmental Protection Agency (EPA) standards, meaning that if a vehicle is equipped with SCR technology, it must use DEF to comply with emission limits.

Since January 1, 2003, all new on-road diesel vehicles in Canada must meet U.S. EPA emission standards, including those requiring DEF. These standards were further tightened with the adoption of Tier 2 (2004-2009) and Tier 3 (2017 onward) emission regulations, which mandate lower NOx levels.

For off-road diesel engines, Canada has harmonized its standards with the U.S. EPA Tier 4 regulations, requiring lower emissions in construction, agricultural, and industrial equipment. Since 2019, even smaller spark-ignition engines have been subject to stricter regulations.

Is Canada’s DEF Regulation the Same as in the U.S.?

Yes, but with some key differences. Canada and the U.S. have harmonized emissions standards, meaning DEF is required in both countries for vehicles using SCR technology. However, there are notable differences in regulatory implementation:

Certification & Labeling – Most diesel vehicles in Canada comply with emissions standards through a U.S. EPA emission certificate, which allows a vehicle certified in the U.S. to be sold in Canada under the concurrent sales principle. However, if a vehicle lacks a U.S. EPA certificate, it must receive Canadian emission approval and display a Canadian-specific emission label.

Warranty Coverage – Unlike in the U.S., there is no federal requirement in Canada for manufacturers to offer an emission-related warranty that covers DEF-related issues, such as failures in SCR systems.

Provincial Control Over In-Use Vehicles

Once a diesel vehicle is sold, Canadian provinces and territories regulate its emissions. This includes:

• Tampering laws: It is illegal to disable or bypass an SCR system.
• Inspection programs: Some provinces, such as Ontario and British Columbia, have emissions testing programs for diesel vehicles to ensure continued compliance.

What Happens If DEF Is Not Used?

Using DEF is not optional for vehicles equipped with SCR systems. If DEF runs out, most modern diesel engines will enter a derate mode, limiting power and speed to encourage refilling. Continuous operation without DEF can trigger engine shutdowns and costly repairs.

Additionally, tampering with DEF systems or using improper substitutes is illegal in Canada. Provinces enforce anti-tampering laws, and businesses caught disabling emission control systems can face heavy fines and penalties.

DEF Supply and Availability

Canada’s DEF supply chain is well-established, with DEF available at most truck stops, fuel stations, and retail locations. However, supply chain disruptions can occasionally cause regional shortages, especially in winter when transportation challenges arise. Fleet operators and truck owners should monitor DEF levels and stock up accordingly.

• On-site DEF storage – Many large fleets maintain bulk DEF storage at their facilities.
• Cold-weather considerations – Since DEF freezes at -11°C (12°F), storage solutions such as heated tanks or DEF tank warmers are essential in Canadian winters.
• Supply chain management: Reliable sourcing of DEF is crucial, particularly in remote areas where availability might be limited.

Looking for a High-Quality DEF in Canada? Look no further!

Mansfield Energy understands the importance of protecting your fleet assets. Today’s high-tech diesel engines are expensive. Using poor quality, off-spec DEF can increase fuel consumption, equipment downtime, and maintenance expenses. Mansfield ensures customers always have a reliable supply of high-quality DEF that consistently meets ISO standards.

With our extensive network of DEF distribution partners combined with our own dedicated assets, Mansfield offers unmatched DEF logistics to ensure you always have the DEF you need. Contact us today!

DEF Equipment Catalog

Looking for the right equipment for your DEF needs? With Mansfield’s DEF Equipment Catalog, you can explore a variety of DEF equipment options and request information or purchase support directly. Check out our online catalog today!