When Is a CRN Required in Canada?

CRN registration is required whenever a pressure-containing component exceeds the pressure and volume thresholds defined in CSA B51 and provincial regulations. Kopfkino Consulting provides compliance reviews to determine whether your specific equipment requires registration.

Equipment Categories Requiring CRN

• Pressure Vessels — tanks, separators, heat exchangers, reactors
• Fittings — valves, flanges, pipe fittings, expansion joints, strainers, filters
• Piping Systems — interconnected piping assemblies above thresholds
• Boilers — steam generators and hot water generators above threshold conditions

Pressure and Volume Thresholds

The typical threshold triggering CRN registration is a design pressure above 15 psig (103 kPa) combined with a volume above 1.5 US gallons (5.7 litres). Provincial regulations vary — Alberta and Ontario apply slightly different criteria for certain categories.

Common CRN Exemptions

• Small bore piping — NPS 3/4 or less is generally exempt in most provinces
• Low-pressure storage tanks — atmospheric or low-pressure tanks below threshold
• Portable fire extinguishers
• Equipment designed for private residential non-commercial use

Frequently Asked Questions

Does small bore piping always avoid CRN?

In most provinces, NPS 3/4 and under piping is exempt. Alberta (ABSA) has stricter rules for certain fluid services. Always confirm with a P.Eng. review.