What Needs a CRN in Canada? Boilers, Pressure Vessels, Fittings and Piping Above 15 psi

By Kopfkino Consulting Corp. · Published September 14, 2026 · 9 min read

Boilers, pressure vessels, fittings and pressure piping above 15 psi (103 kPa) generally need a CRN in Canada. The four registration scopes, common exemptions and a decision framework.

In Canada, a CRN is generally required for the design of any boiler, pressure vessel, fitting (CSA B51 Categories A-H), or pressure piping system holding expansible fluids above 15 psi (103 kPa). Registration is provincial; exemptions differ by province. Confirm with the authority having jurisdiction.

The question "does my equipment need a CRN?" usually arrives when a Canadian customer or inspector asks for the number, and you do not have one. Short answer: most pressure equipment designed above 15 psi (103 kPa) must have its design registered in each province of installation. The long answer depends on equipment type, size, fluid and destination province. For what a CRN actually is (a design registration, not a product certification) see What Is a CRN?.

What is the 15 psi (103 kPa) pressure trigger?

Canadian pressure-equipment regulation is built on CSA B51, adopted by law in every province and territory: pressure-retaining equipment designed for greater than 15 psi (about 103 kPa) falls within the regulatory system. Ontario states the boundary directly: O. Reg. 220/01 s. 2(2)(d) exempts equipment whose maximum allowable working pressure does not exceed 15 psi, and TSSA's Fitting Registration Guidelines apply the same trigger to fittings.

Two clarifications: the test is design pressure, not operating pressure (a system running at 10 psi but designed for 50 psi is in scope); and crossing 15 psi does not dictate how equipment registers, scope and exemptions come next.

The four registration scopes

1. Boilers. Boilers built to ASME Section I (power) or IV (heating) require design registration before construction. Small units are commonly excluded (Quebec's r. 6.1 s. 3 excludes power boilers at or below 1 m² heating surface or 10 kW), and thresholds differ by province.

2. Pressure vessels. ASME Section VIII vessels (air receivers, separators, filter housings, exchanger shells) require design registration. The key boundary is the CSA B51 pressure-volume/diameter classification (Figures 1(a)-(c)): items below roughly 6 in (152 mm) inside diameter or 42.5 L (1.5 ft³) may be classed as Category H fittings, or exempted, depending on the province. See Vessel or Category H Fitting?.

3. Fittings (CSA B51 Categories A-H). "Fitting" covers every pressure-boundary component of a piping system except the pipe itself: couplings, tees and reducers (A); flanges (B); valves (C); expansion joints and hose assemblies (D); strainers, filters and steam traps (E); gauges and transmitters (F); capacity-rated relief devices (G); and everything else pressure-retaining, including small vessels and compact assemblies (H). Pipe itself is material and needs no CRN. Fitting registrations expire 10 years after first acceptance. Details: Fitting CRN Registration in Canada.

4. Pressure piping systems. Piping conveying expansible fluids (steam, air, gases, and certain hazardous or high-temperature liquids) requires registration of the system design (P&IDs, line lists, specs and calculations) typically to ASME B31.1, B31.3 or B31.5, and carries aggregate volume thresholds in several provinces.

Common exemption patterns, and why they are province-specific

There is no national exemption list: each province legislates its own. Recurring patterns (confirm current text with the AHJ before relying on any):

Three cautions: the list is province-specific: the BC/SK/MB standard-fitting exemption is false in Alberta, Ontario and the ACI Central jurisdictions; exemption from registration never exempts the governing act and code; and every threshold is CONFIRM-WITH-AHJ: regulations are amended and current interpretation governs.

Machinery and refrigeration exclusions

Machinery: components integral to rotating or reciprocating machinery (pumps, compressors, turbines) whose primary stresses derive from the device's function are excluded (Alberta PEEO s. 2(2)(j); Ontario s. 2(2)(m); Quebec r. 6.1 s. 3), but a whole compressor skid is not: its receiver, separators, coolers and interconnecting piping remain regulated. Refrigeration: CSA B52-governed systems below province-specific capacities are excluded or exempted (ON ≤ 11 kW; AB ≤ 10.5 kW; QC ≤ 125 kW; SK ≤ 3 tonnes; NS ≤ 11 kW). Equipment under other regimes (TDG transport, Z662 pipelines, B149 fuel gas) sits outside the BPV stream, though pressure equipment inside such facilities often remains in scope.

Decision framework: does my equipment need a CRN?

For each destination province, work through five questions:

• In the regulatory universe? A boiler, pressure vessel, fitting, or pressure piping system designed above 15 psi (103 kPa)? Below that, or excluded as machinery/TDG/pipeline/fuel-gas equipment, registration generally does not apply.
• Which scope? Boiler, vessel, fitting (A-H, including the Category H small-assembly path), or piping system? Classification determines the route.
• Does a provincial exemption apply? Check the destination's size, volume, fluid and temperature thresholds; document the basis in writing.
• Design or installation registration? Vessels, boilers and fittings register as designs (one CRN covers unlimited identical units); piping registers as a system; Quebec registers piping via the installer's declaration of installation (r. 6.1 s. 32).
• Where will it be sold or installed? Registration is per jurisdiction. Alberta always requires its own ABSA review; several provinces route through ACI Central.

Worked scenario: a 200 L air receiver sold into Ontario and Alberta

A manufacturer builds a standard 200 L vertical air receiver (250 psi design, with a relief valve, pressure gauge, drain valve and short discharge spool), and sells it into Ontario and Alberta. At 200 L the receiver sits above the 42.5 L / 152 mm exemption thresholds, so it needs vessel design registration in both provinces: TSSA for Ontario, plus a separate ABSA review for Alberta. Next, the fittings audit: the relief valve (Category G), gauge (Category F) and valves (Category C) each need their own CRN. Alberta has no categorical fitting exemption, and Ontario registers standard fittings too. Finally, the piping threshold check: test the spool against Alberta's 0.5 m³ aggregate-volume exemption, splitting systems to stay under it is not permitted. The vessel CRN does not expire; the fitting CRNs lapse after 10 years.

What "sale" and "installation" triggers mean for sellers

Registration duties attach to events: Ontario prohibits manufacturing pressure equipment for use in Ontario unless the design is registered (O. Reg. 220/01 s. 4(1)); BC requires registration before construction is commenced (s. 84(5)); Quebec requires approval before equipment is put on the market (r. 6.1 s. 29). Sell without a CRN and the risk lands on your customer: installers cannot obtain permits and inspectors can refuse the equipment. Packaged-equipment sellers face an added decomposition step: vessels, fittings and interconnecting piping are assessed separately. See Does My Skid Need a CRN?.

Common mistakes

• Assuming one CRN covers Canada. Each jurisdiction registers separately; Alberta is outside the reciprocal Reconciliation Agreement, and Atlantic/territorial jurisdictions route through ACI Central.
• Over-applying exemptions. The BC/SK/MB standard-fitting exemptions do not exist in Alberta or Ontario; splitting piping into sub-0.5 m³ skids to dodge Alberta's aggregate-volume threshold is explicitly not permitted.
• Ignoring the 10-year fitting expiry. Fitting CRNs lapse and must be resubmitted; vessel registrations do not expire but must meet the code edition current at fabrication.
• Missing fittings nested inside packages. Every valve, strainer, gauge and relief device in a skid needs its own CRN or documented exemption; Ontario piping registrations require attesting that only registered fittings are used.

Best practices

The following are engineering recommendations, not regulatory requirements:

• Build a destination-province matrix per product line: scope, thresholds, exemption basis, registration status.
• Classify borderline items with the CSA B51 Figures 1(a)-(c) graphs before choosing vessel vs. Category H registration.
• Register before fabrication (in BC, before construction starts); retroactive registration can be expensive or impossible.

Frequently Asked Questions

Does my equipment need a CRN if it operates above 15 psi in Canada?

Generally yes. Boilers, vessels, fittings and pressure piping systems designed above 15 psi (103 kPa) require design registration in each province of installation unless a provincial exemption applies, design pressure, not operating pressure, is the test.

Does a small pressure vessel need a CRN?

Often registered differently rather than not at all: at or below roughly 42.5 L or 152 mm ID, vessels may be exempt (Ontario, Alberta), registered as Category H fittings, or (in Nova Scotia) still registered as fittings despite a permit exemption.

Do standard catalogue fittings like flanges and valves need CRNs?

Province-dependent: BC, Saskatchewan and Manitoba exempt Category A, B, C and G fittings built to listed ASME standards; Alberta, Ontario and the ACI Central jurisdictions register them.

If my equipment is exempt in one province, is it exempt everywhere?

No. Exemption lists are enacted province by province and differ materially, equipment exempt in Ontario may require registration in Alberta, and vice versa.

Does a CRN expire?

Fitting registrations expire 10 years after first acceptance. Boiler and vessel registrations generally do not expire, but the design must meet the code edition in force at fabrication.

Key Takeaways

• Above 15 psi (103 kPa) design pressure, most boilers, vessels, fittings and pressure piping systems need a CRN in each province of use.
• Registration splits into four scopes: boilers, vessels, fittings (A-H), piping systems, each with its own route.
• Exemption thresholds (42.5 L / 152 mm vessels, 0.5 m³ piping aggregate, standard-fitting categories, refrigeration capacities) are province-specific; never generalize them.
• Exemption from registration is never exemption from the governing act or code, so register before fabrication or sale; retrofitting compliance is costly and sometimes impossible.

Related Guides

• What Is a CRN (Canadian Registration Number)? Pressure Equipment Design Registration in Canada Explained
• Vessel or Category H Fitting? CSA B51 Size Rules (42.5 L / 152 mm) That Decide Your Registration Path
• Fitting CRN Registration in Canada: CSA B51 Categories A-H and Provincial Exemptions
• Does My Skid Need a CRN? A Decision Guide for Equipment Bound for Canada
• When is a CRN required in Canada?
• CRN for pressure vessels: overview
• CRN for piping systems: overview
• CRN 101: What It Is, What Needs It, and How to Apply

Sources

• Ontario, O. Reg. 220/01 (Boilers and Pressure Vessels): https://www.ontario.ca/laws/regulation/010220
• TSSA, Fitting Registration Guidelines (Jan 2026, Rev 3): https://www.tssa.org/downloads/fittings-guidelines-jan-2026-rev-3
• British Columbia, BC Reg. 104/2004: https://www.bclaws.gov.bc.ca/civix/document/id/complete/statreg/104_2004
• TSBC, Directive D-BP-2013-03 (fitting registration exemptions): https://www.technicalsafetybc.ca/regulatory-resources/regulatory-notices/directive-exemption-registration-requirements-category-b-c-and-g-category-fittings
• Alberta, Pressure Equipment Exemption Order AR 56/2006: https://kedkep.com/docs/Safety%20Code%20Act%20PEEO.pdf
• TSASK, Design Registration hub: https://www.tsask.ca/boilers-pressure-vessels/design-registration/
• Manitoba, Exemption bulletin its_20_009: https://www.gov.mb.ca/asset_library/en/labour/docs/its/its_20_009_exemption_from_registration_requirements_for_categories_a_b_c_and_g_fittings.pdf
• Quebec, Regulation respecting pressure installations, c. B-1.1, r. 6.1: https://legisquebec.gouv.qc.ca/en/ShowDoc/cr/B-1.1,%20r.%206.1
• Nova Scotia, Boiler and Pressure Equipment Regulations: https://novascotia.ca/just/regulations/regs/tsboiler.htm
• CSA Group, CSA B51:24: https://www.csagroup.org/store/product/2701790/

Determining what needs a CRN is where first-time sellers lose weeks. Kopfkino Consulting supports manufacturers, OEMs, EPCs and fabricators with CRN applicability assessments, multi-province registration strategy, design review before fabrication, calculations and submission packages, P.Eng. coordination, and regulator-comment resolution. Unsure whether your equipment triggers registration? An early scoping review is the lowest-risk place to start.

Contact us to discuss the registration scope for your equipment and its destination provinces.

Topics: CRN Registration, CRN Fundamentals, 15 psi Rule, Pressure Piping