Current edition: CAN/CGSB-3.517-2025, supersedes CAN/CGSB-3.517-2020. Issued by the Canadian General Standards Board.

What the 2025 update changed

• Absorbed the prior CAN/CGSB-3.520 (biodiesel blends B1–B5). The 2025 edition allows up to 5% biodiesel in the base spec; B1–B5 no longer has its own separate document.
• Re-keyed the low-temperature classification to the 2.5% low-end design temperature (Environment Canada hourly statistical basis over 30 years) rather than a fixed CFPP target.

Type A vs. Type B

• Type A — higher-grade winter product for colder 2.5% low-end design temperatures. Used for urban transit, mining, and northern Ontario mid-winter operations.
• Type B — standard high-speed diesel suitable for SWO shoulder seasons and moderate winter. Typically supplied at CFPP −20 to −34 °C in Eastern Canada depending on month and refinery.

Seasonal switchover at Ontario terminals runs progressively late October through November (summer → winter blend), reversing March–April. SWO operators typically take Type B; northern Ontario operators may need Type A in deep winter.

The Canadian normative reference for CFPP

The Canadian normative reference for cold filter plugging point is CAN/CGSB-3.0 No. 142, embedded in CGSB-3.517. International equivalents (ASTM D6371, EN 116) are also valid test methods; ISO 3104 is the kinematic viscosity method referenced for cold-weather operability.

Cross-reference

For SWO climate context and the practical CFPP margin question on extreme-minimum nights, see SWO winter climate normals — Waterloo and London design temperatures for diesel operability and (unpublished reference).

Sources & structured attribution

• source.document: Canadian General Standards Board — CAN/CGSB-3.517-2025 Automotive low-sulphur diesel fuel (publications.gc.ca); DieselNet Canada fuel specifications page (dieselnet.com/standards/ca/fuel.php)
• source.captured_date: 2026-05-16
• concept_category: fuel specification / winter operability
• applies_to_services: clear diesel, dyed diesel, winter diesel additive program