Guide to CRN Numbers

Pressure Vessel Engineering provides services in all aspects of CRN registration. See our advertisement below.

Vessel CRN Numbers

Vessel registration numbers most commonly follow the format suggested by CSA B51-14 4.3.2.

Vessel CRN Numbers

The CSA B51 CRN format is an initial letter followed by 3 to 5 digits, a decimal point and the next digit which specifies the province of first registration. Additional digits indicate other provinces that have also accepted the design.

CRN Numbers

Actual CRN numbers can deviate from this format, but usually not widely.  Here are some real numbers illustrating common variations:

A2170.8 A vessel registered in Nova Scotia: note the standard format used of a letter, 4 digits, decimal point, and provincial of first registration (8 = Nova Scotia).
K2478.15 Another conventional CRN: a letter, 4 digits, decimal point, province of first registration (1=B.C.) followed by another province that has also accepted the design based on re-review or acceptance of the first provinces review (5 = Ontario).
D07726.6 A Quebec issued 5 digit number (The first digit is kept 0 to allow Alberta compatibility).  If this vessel was also reviewed by Alberta, the ABSA returned CRN would be D7726.62, dropping the leading zero.
1811.9 A CRN with no starting letter – issued by ACI for use in Prince Edward Island.
8340.35 Another CRN with no starting letter – this one issued by Saskatchewan (3), later accepted by Ontario (5)
769.T rev.1 3 digit Northwest Territories format, revision 1. No leading letter.

Vessels and fittings must be registered in each province where they will be used.  The order that the different provinces reviewed the same design is a critical part of the CRN system.  A1234.51 (vessel registered first in Ontario, later the same design accepted in B.C. is not the same vessel as A1234.15 (vessel first registered in B.C., later also accepted in Ontario).

The jurisdictions also issue special numbers for unusual circumstances:

5AN7004 A single use registration for used or altered vessels in Ontario.
X0740.2 An Alberta issued used vessel
PD08583.6 A Quebec issued heat exchanger, 5 digit format
ALD-14-016 Alberta Limited Design on a cold stretched vessel – This registration is limited to a list of serial numbers and a list of ultimate vessel owners.
ACCEPT536 An Ontario variance on an unusual design.  Typically to a non-ASME code of construction.

A map of Canada showing the digits/numbers for the different provinces:

CRN Numbers

The digits after the decimal place indicate which provinces have accepted the design. The first province of acceptance always follows the decimal point. If a CRN is to be updated, revised or renewed it must be re-accepted by the first province before the others can also accept it.

Re-used letters and Unique CRNs

The starting letter is not always unique to a province. The fictitious CRNs A1234.23 and A1234.32 are two different vessels, the first registered in Alberta, and then in Saskatchewan. The second, a different vessel, is first registered in Saskatchewan, and then Alberta. The CRN number cannot be guaranteed to be unique until the first province of registration as indicated by the first digit after the decimal point is included.

P1405.4 Manitoba number for a vessel. Manitoba = .4
P9136.25 Alberta issued vessel, using the same starting letter as Manitoba. Alberta = .2

Multiple CRNs on One Vessel

One of our first large registration jobs was for a line of standard vessels registered Canada wide. Our customer had been applying for CRNs across Canada as required without referencing previous registrations for the same vessels elsewhere in Canada.  Each vessel ended up with many different CRN numbers, added as they were sold into new provinces.  The CRN for the province being sold into was being stamped into the nameplate before shipping.  This worked only as long as the ultimate province of use was known at the time of production and the vessel was not re-sold.  Problems arose as the vessels were sold to one province, put on skids and shipped to another – additional CRN numbers had to be stamped onto the nameplates in the field.  Stamping all the CRN numbers in the nameplate was not practical due to space limitations. Canada wide registrations based on one number per vessel solved this problem.

Fitting CRN Numbers

Fittings must be registered in individual categories.  This can increase registration costs and paperwork for companies with products that span more than one category.

Fitting CRN Numbers

CSA B51-14 Table 1: Categories of Fittings
Category Type of Fitting
A Pipe fittings, including couplings, tees, elbows, wyes, plugs, unions, pipe caps, and reducers
B All flanges
C All line valves
D All types of expansion joints, flexible connections, and hose assemblies
E Strainers, filters, separators, and steam traps
F Measuring devices, including pressure gauges, level gauges, sight glasses, levels, and pressure transmitters
G Certified capacity-rated pressure relief devices acceptable as primary overpressure protection on boilers, pressure vessels and pressure piping, and fusible plugs
H Pressure-retaining components that do not fall into Categories A to G

Some typical fitting registration numbers:

0A5983.1 Category A piping fitting issued by BCSA.
0B09081.234567890YTN Category B flange registration issued by ABSA. Registration was not required or not available in B.C. Registration is no longer required in Saskatchewan, but was requried at the time of registration.
0B09081.2CL Same fitting, accepted Canada Wide abbreviation because BC is not required, note TSASK has been issued but is no longer required and could be dropped at the time of renewal. The “CL” designation indicates that the number has been issued everywhere it is required.
0C07555.2C Category C valve fitting, first issued by ABSA, registered Canada Wide. This fitting no longer needs registration in Saskatchewan. Registration in B.C. is currently still required because the design is not listed in the B31 piping codes.  If registered today it would be 0C07555.2CL
0H10655.5ADD1 Addenda of an Ontario CRN, first issued by Ontario. See addends below.
R0292.51467890YTN FITG A category “H” fitting that must be registered as a vessel, like a dental autoclave, which is too small to be a vessel but must be registered as a vessel regardless – or – a category “H” item which contains both vessel and fittings (a line of products that starts off fitting size but becomes vessel as a dimension like length changes).
FITG can also indicate an item that was first registered as a pressure vessel in a province other than Ontario, but is defined as a fitting in Ontario. Usually there is no statutory declaration.


Fitting registrations expire 10 years after issuing. An addendum updates some details of an application, but the clock is not reset. For example, a CRN addended 5 years after issue will still expire after 5 more years (or 10 years after the original registration date).

0C12887.5C A valve registration issued by Ontario, accepted Canada wide.
0C12887.5CADD1 One year later, the scope of registration has been expanded and accepted Canada wide. Additional valves or configurations have been added to the scope of registration, but the original registration has not been reviewed to save time and cost. The expiration date remains the original date.  The latest code in effect at the time of addenda is used to cover the addenda.
0C12887.5CADD2 Again, the CRN has been addended, and again only the additional scope has been reviewed by the jurisdictions. The expiry date remains that of the first registration.  Again, the latest code in effect at the time of addenda is used to cover the addenda.


A revision requires the examination of the complete file against the current code edition, (not the edition in effect for the date of original submission). The revision process must start at the first province to maintain the original number and then be repeated with all other provinces where registration was already completed. Once complete, the revision maintains the original expiry date from the initial submission.

0A5609.5 CRN issued by Ontario for a standard category A fitting (pipe fittings, including couplings, tees, elbows, wyes, plugs, unions, pipe caps, and reducers). The registration expires in Ontario 10 years after the date of issue.
0A05609.52467890YTN The CRN after all jurisdictions have accepted it. The registration expires everywhere on the Ontario expiry date. This standard category A fitting does not require registration in B.C. or Saskatchewan (“1” and “3” are missing from the number).
0A05609.5CL A convenient short form indicating that the fitting has been registered everywhere it is mandatory. The shortform is created by the customer, not the jurisdictions (unless the Canada wide registration is done by a jurisdiction).
0A5609.5R1 The CRN has been revised with Ontario, the first province of registration. The CRN now expires in Ontario 10 years after the revised CRN date.
0A5609.52 Alberta has accepted the revised CRN, Alberta does not include revisions or addends in the CRN number.  The fitting can be used for new designs in Alberta until the Ontario expiry date.
0A05609.52467890YTNR1 The revised CRN has been accepted by the remaining jurisdictions. The CRN is now acceptable everywhere until the new Ontario expiry date.
0A05609.5CLR1 Again the convenient short form indicating that the revised fitting has been registered everywhere it is mandatory. The R1 notification that was not included in the Alberta registration will be ignored if it is used in Alberta submissions.


Saskatchewan standard category A, B, C and G fittings are exempt.

British Columbia standard category A, B, C and G fittings are exempt.

Manitoba standard category A, B, C and G fittings are exempt.

Shortening a CRN Number

The CRN number can become quite long after all of the provinces have signed off on it. Methods of shortening the number are discussed.

Shortening a CRN Number

A design registered across Canada can have the CRN number shortened to make it a little easier to read.  The letter “C” indicates that the vessel has been registered in the rest of Canada. The letters CL can be used to indicate that a fitting has been registered everywhere it is required to be registered.  See CSA B51-14 4.3.2 Notes(2) and (3).

4.3.2(2) If a design is registered in all provinces and territories, the CRN stamped on the nameplate and marked on the data report may be shortened to include the designation of first registration plus the letter “C”, e.g., K4567.5C.

4.3.2(3) If a design is registered in all provinces and territories that require registration but not in provinces and territories that do not require registration, the CRN may be shortened to include the designation of first registration plus the letters “CL”, e.g., K4567.5CL. (The “L” means limited.)

We registered this Category “A” breakaway connector Canada wide, starting in Alberta:

0A12396.2 A Category A fitting, 5 digit form originally issued by Alberta Boilers and Safety Association (ABSA) for Alberta use. Copies of the original registration were then sent to the other jurisdictions for reciprocal registration.
0A12396.21 As Accepted by B.C. Safety Authority (BCSA) for use in B.C. (trailing digit “1” added by BCSA for B.C. acceptance).
0A12396.23 As accepted by Technical Safety Authority of Saskatchewan (TSASK) for Saskatchewan use. “3”
0A12396.24 As accepted by Manitoba Office of the Fire Commissioner for use in Manitoba. “4”
0A12396.25 As accepted by Technical Standards and Safety Authority (TSSA) for use in Ontario. “5”
0A12396.26 As accepted by Service de l’inspection de la fabrication (RBQ) for use in Quebec. “6”
0A12396.27890YTN As accepted by ACI Central, Inc. for use in New Brunswick, Nova Scotia, Prince Edward Island, Newfoundland and Labrador, Yukon, North West Territories and Nunavut. “7890YTN”
0A12396.2134567890YTN Same CRN, combined to show Canada wide acceptance.
0A12396.2C The acceptable short-from indicating that this break away connector is registered Canada Wide.
0A12396.124567890YTN The same fitting registration if it was applied for today. Saskatchewan no longer registers Categories A, B, C and G.  B.C. and Manitoba registration would be required because this item is not listed in a B31 standard.
0A12396.2CL The acceptable short-form indicating that the fitting is registered everywhere it is required.

The jurisdictions do not combine the CRN digits to create the Canada wide registration number. It is up to the applicant to do that after all of the provinces have signed off. Be careful of when to use the “C” and “CL” designation. “CL” Can only be used on fittings that are exempt in the provinces not registered.

Piping Registration Numbers

Piping Registration Numbers

P6947 A BC issued piping registration.
P36879 This Ontario issued piping system does not clearly show the province of registration.
P37373ADD1 An Ontario issued piping system, addended.
PP03373.0 A Piping system registered in Newfoundland
PP0060.7A2 Piping issued in New Brunswick.
PP581-1888 A piping system registered in Saskatchewan.
PSTD38354 A mobile piping system registered in Ontario. The same format is used for multiple build standard piping systems.
“ “ Quebec does not issue piping CRNs. On-site inspection is used instead. Ship the documents that you would use to support a CRN with the piping system for the AI to review on site before granting system start up.
P1405.4 A Manitoba VESSEL – the “P” at the start does not always mean piping.

PP-0701-E-004-P, PP-0701-E-004-P

Alberta registered piping system. The same number has been issued to one vendor working on different skids.

Piping registration is usually limited to one address of installation. Mobile and repeat builds of identical piping systems represent a challenge.  Some jurisdictions will classify the piping system as an oversize fitting to allow repeat builds.  Alberta has implemented mobile registration (Mobile Pressure Piping).

CRN Registration at PVEng

We have helped more than a thousand customers to secure CRN registrations across all jurisdictions. We are experts in the specialized field of pressure equipment design and registration.

  • Integrated design, review and registration services
  • Extensive knowledge of registration requirements, including what needs registering and what is exempt province by province
  • We work to many ASME codes – VIII-1, VIII-2, I, IV, B31.1, B31.3, B31.5 and others
  • Design validation by burst test to many codes

Other Services

ASME Code DesignWe work to many ASME standards to design and validate pressure vessels, boiler, fittings and piping systems.

Finite Element Analysis (FEA)We use FEA to design and validate fittings and vessels that cannot be designed by rule-based codes like VIII-1 or B31.3.

Pipe Stress Analysis Pipe stress analysis is mandatory for British Columbia registration and it is recommended practice for many other systems.

About Us

Pressure Vessel Engineering has twenty years of successful experience in the pressure vessel field working for more than a thousand customers.

  • Ten Professional Engineers on staff licensed to stamp and sign off on designs for use in all Canadian jurisdictions.
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