Guide to CRN Numbers

PVE-8296 LRB Revised and Clarified Sept 1 2016

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Vessel CRN Numbers

Vessel registration numbers most commonly follow the format suggested by CSA B51-14 4.3.2: 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 varies 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 A1234.1.5 (vessel first registered in B.C., later also accepted in Ontario).

The need to register vessels and fittings in each and every province that they will be used in is one of the most aggravating, expensive and time consuming aspects of the CRN system.  Multiple registration does not mean that the vessel has been reviewed multiple times.  Per CSA B51-14 4.2.2:

Initial registration with one regulatory authority may be accepted by the regulatory authority in another province if the latter is provided with an accepted copy of the statutory declaration form (see Figure D.6) and the supporting documentation specified in Clause 4.2.8.

When other provinces accept the initial review, the process goes faster and the costs are lower, but this acceptance varies by province and reviewer.  Regardless whether the vessel is reviewed multiple times or not, lots of paper is involved.  Each province follows their own documented, undocumented and reviewer specific rules.  To increase your odds that your design will be accepted across Canada it is best to stick to design elements that clearly follow code written and illustrated requirements and have been in the ASME code for a number of years.

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.  These are rare and hard to get.

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.

Another temporary case of multiple stamping arose when Ontario started issuing five digit CRNs in 2013. Unfortunately Alberta’s registration software is not able to process five digit vessel numbers.  Alberta issued new CRN numbers that would fit in their system.  (The five digits used in fitting registrations is not a problem.)  Ontario has since returned to using four digit numbers to avoid this problem but the vessels can still be found in the field.

M10007.513467890YTN, V7038.2 An Ontario issued 5 digit CRN.  The design was accepted Canada wide, but ABSA’s system could not handle the 5 digits so they issued a new number.  Both CRNs had to be put on the nameplate to make future moves easier.  It is not possible to create a short form of this CRN.
M10060.51367890YTN, W4343.2 Another example of the same Ontario – Alberta 5 digit CRN problem.  Put both CRNs on the nameplate.
D08634.6, D8634.62 A Quebec issued 5 digit registration number and the same vessel accepted by Alberta. The first zero after the letter is dropped by ABSA.
D09741.6, E00099.6 The last “D” series and the first “E” series Quebec numbers issued to us. Quebec did not increment the first digit form 0 to 1 to maintain Alberta compatibility, instead the letter was changed.
AA1234.2 Expected future Alberta double letter format once single letter numbers have been used up.

As shown above, Quebec also issues five digit CRNs, but has kept the first digit 0, which Alberta drops from the registration. Alberta has almost run through all the single digit letters. A new double letter system is expected after CRN Z9999.2, probably starting with AA0001.2 This 4 digit limitation does not apply to fittings – for example 0C10790 is a valve CRN issued by Alberta. Hopefully other provinces will not have difficulty handling the double letters.

Fitting CRN Numbers

For reasons that can no longer be remembered, fittings must be registered in individual categories.  Unfortunately this increases registration cost and paperwork for companies with products that span more than 1 category. Per CSA B51-14 4.2.2:

Each category of fitting manufactured (see Table 1) shall be separately registered by the manufacturer with the regulatory authority…

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
Note: Categories A, B, C and G fittings are exempt in Saskatchewan. Standard A, B, C and G fittings are exempt in B.C.*

*For B.C., a standard fitting is one that is listed in the B31.1, B31.3 and B31.5 standards.  Per BCSA Directive NO: D-BP-2013-03

Nonstandard or unlisted piping components not complying with the specifications and standards listed the ASME B31 Code for Pressure Piping or pressure relief devices not in compliance with the requirements of the ASME Boiler and Pressure Vessel Code, shall be registered in accordance with Section 84(2) by submitting the documentation specified in CSA B51 section 4.2.6(b).

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 repeated with all other provinces also registered in. Once complete, the revision extends the expiry clock to 10 full years from the date of revision.

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.
OA05609.52467890YTN 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).
OA05609.5CL 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.
OA05609.52467890YTNR1 The revised CRN has been accepted by the remaining jurisdictions. The CRN is now acceptable everywhere until the new Ontario expiry date.
OA05609.5CLR1 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.


A renewal is required after the fitting registration expires on its 10th anniversary if it will still be sold into new piping systems or installed on a new vessel. Only fittings expire, not pressure vessels or piping systems. The end user must keep the piping system or vessel according to the original registration. Changes in fittings used will require revised registration. The expiry prohibits the use of the fitting in new registered vessels or piping systems, it does not mean that the existing fittings currently in use have to be removed from service.

In theory the renewal is now easier according to CSA B51-14 4.2.8(c):

for the resubmission for validation required by Clause 4.2.1 (provided that the documentation specified in Item (a) or (b) was provided to and evaluated by the regulatory authority and is still applicable, and that Clauses 4.1.2 and 4.1.4 do not apply): (i) a properly completed statutory declaration form for the registration of fittings; (ii) a copy of the manufacturer’s valid quality control program certificate; and (iii) the scope of product registration within the original registration.

This is much simpler than original submissions, and cannot include items that were not in the original submission, but does this work? In practice this varies. Some reviewers accept renewals within the same scope with just items (i), (ii) and (iii) and do a quick registration at low cost. However some reviewers require a full re-submission of all documents originally submitted and go through a complete technical review. We do not know which reviewer we will get at time of renewal so we start with submitting items (i), (ii) and (iii) as required by the standard, and which often works, and supply more materials as required. Obviously the cost varies considerably by reviewer.

0B8237.5 A flange CRN issued by Ontario.
0B8237.5R1 The CRN has been renewed by Ontario and is valid for another 10 years from the renewal date. The R1 nomenclature is identical to that used on a revision and in both cases is good for another 10 years.


CSA grants CRNs, but they are only acceptable in Quebec and Saskatchewan.

CSA-0F10904.56 A measuring device CRN issued by CSA. CSA subcontracted the review to Ontario which issued a number 0F10904.5. CSA added the Quebec designation. Because this is a CSA CRN, it is also valid in Saskatchewan even though it is not include in the CRN number.
0F10904.5 The CRN as it was issued by TSSA to when contracted to review the job by CSA.

In this case CSA used Ontario’s review as the basis of their Quebec registration. This is the remnants of what was to become a Canada wide fitting registration system. This attempt failed, but as of 2015 rumours of another attempt at creating a one stop Canada wide registration system based in CSA are circulating once again.


A fitting is not required to be registered in Saskatchewan pursuant to The Boiler and Pressure Vessel Act if:

It is registered by CSA;

It is a category A, B, C, or G fitting, as set out in the CSA B51 code

British Columbia

From BCSA D-BP 2013-03 for more information.

Exemption of Category A, B, C, and G fittings from registration.

The exemption of fittings from registration shall apply only to piping components complying with the standards and specifications listed in the ASME B31 Pressure Piping Codes and to certified pressure relief devices complying with the requirements of the ASME Boiler and Pressure Vessel Codes.

Non-standard or unlisted piping components not complying with the specifications and standards listed the ASME B31 Code for Pressure Piping or pressure relief devices not in compliance with the requirements of the ASME Boiler and Pressure Vessel Code, shall be registered in accordance with Section 84(2) by submitting the documentation specified in CSA B51 section 4.2.6(b).

CSA-0F16276.56 A fitting registered in Ontario, then in Quebec through CSA. Saskatchewan use is also allowed because the CSA registration from Quebec (the only other province allowing CSA).

Shortening a CRN Number

The CRN number can become excessively long after all of the provinces have signed off on it. 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. 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 in.

Piping Registration Numbers

Per the B51 standard, any number of copies of a piping system can be built from one registration (B51-14 4.1.2):

Any number of boilers, pressure vessels, fittings, fired-heater pressure coils, and piping systems may be constructed from a registered design until a change in the applicable Act, codes, or standards invalidates the design, in which case the design shall be obsolete and no further construction to the design shall be made after the effective date of the change as established by the Act.

However, not all provinces have managed to achieve this level of flexibility. The most fundamental stumbling block is that some provinces require the address of installation for each registration. In theory multiple copies of piping systems can be built for the same address, but building it again for a new address is not allowed. In Ontario PSTD registration numbers are issued for piping systems that will be mobile or built repetitively.

While other provinces continue to refine their processes, several workarounds are in use: 1) register your piping system every time it is sold to a new location; 2) some provinces will issue piping systems too big to be a fitting a fitting number allowing it to be built multiple times.

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.

Registration Mistakes

Watch out for jurisdiction paperwork issues. About 1 in 20 issued CRN forms have wrongly listed drawing numbers, or CRN numbers on returned drawings not matching the number on the official paperwork making the registration paperwork unusable. Review the paperwork you get back and ask for corrections as required.

Currently it can take up to half a year to get registration paperwork back from Alberta AFTER the registration number has been granted by email or verbally. It is not possible to continue reciprocal registration in other provinces without the official paperwork. This is one reason why we do not currently use Alberta as a first province of registration on Canada wide projects.

Also watch out for these common mistakes when filling out paperwork:

BPV-D-09-01042 This is an Ontario tracking number, not a CRN!
OE07435.2 Wrong form – the first digit in this fitting registration is a “Zero”, not the letter “O”. The correct form is important if searching for product registrations.
0h10173.5 Fitting registered in Ontario, bad form – use capitals for the letters. This one is not critical, it just looks strange.
0H10173.5 The same fitting in correct form, all letters uppercase.