CO2 Refrigeration System Compliance Screening: ASHRAE 15 and IIAR CO2
CO2 Refrigeration System Compliance Screening: ASHRAE 15 and IIAR CO2
Engineering summary
For a CO2 Refrigeration System proposed for a US code-context commercial refrigeration or cold-room project, the pre-RFQ compliance task is to identify the named references that need to be addressed before equipment scope, supplier deliverables, and project engineering responsibilities become fixed. The supplied code-context reference identifies ASHRAE 15 and IIAR CO2 as compliance references for refrigeration systems using carbon dioxide (CO2). [1]
This is a screening conclusion, not a clause-level design conclusion. It means the procurement team should place both references in the project compliance register, ask the supplier to identify how its proposed package relates to the project compliance basis, and assign responsibility for project-specific engineering and local review. It does not mean that a supplier statement alone establishes that an installed system satisfies every applicable requirement.
The important commercial distinction is between a packaged equipment offer and the installed refrigeration system. A supplier may describe the equipment supplied; the project team must still establish the installation location, local code pathway, final system boundary, interfaces, and the party responsible for detailed compliance review. Jurisdictional adoption and local requirements should be confirmed for the actual project location.
When CO2 compliance screening belongs in refrigeration procurement
Compliance screening should occur before RFQ release, supplier approval, or a commitment to a particular CO2 refrigeration-system package. At that stage, the buyer is not yet selecting charge, capacity, piping arrangement, ventilation provisions, detection equipment, relief arrangements, electrical design, or acceptance tests. Those matters are outside this screening note and require project-specific engineering.
The initial decision is narrower: does the proposed scope use CO2, and therefore need ASHRAE 15 and IIAR CO2 included in the project’s compliance-reference screen? The answer should be recorded rather than left as an assumption in a quotation or supplier datasheet. The 2024 International Mechanical Code source record used for this guide identifies ASHRAE 15 and IIAR CO2 in connection with CO2 refrigeration-system compliance. [1]
Early identification reduces a common procurement risk: releasing an RFQ that asks only for a product description and price, while leaving the compliance basis undefined until after a supplier has been selected. A later discovery that a project requires additional engineering inputs, documentation, or local review can create unclear ownership even where the equipment itself is technically suitable.
System boundary: what is being procured?
For this guide, the procurement object is a CO2-based refrigeration-system package considered for commercial refrigeration or a cold-room project. The compliance screen must distinguish this package scope from the complete installed system and from the project approval process.
| Boundary item | Question to resolve before RFQ release | Typical owner to assign |
|---|---|---|
| Proposed refrigerant basis | Does the proposed refrigeration-system scope use CO2? | Buyer or project owner, confirmed with the proposing supplier |
| Equipment package | What equipment, documentation, assumptions, and exclusions are included in the supplier offer? | Supplier |
| Installed project system | Who is responsible for project-specific engineering and installation compliance review? | Project owner to designate |
| Project location | Which jurisdiction and local approval pathway apply to the installation? | Project owner and qualified local professionals |
| Compliance-reference register | Have ASHRAE 15 and IIAR CO2 been screened and recorded for the proposed CO2 scope? | Compliance manager or designated project lead |
The table does not allocate legal responsibility by itself. Its purpose is to ensure that ownership is explicitly assigned in the RFQ and project governance record.
ASHRAE 15 and IIAR CO2 in the procurement screening scope
ASHRAE 15 and IIAR CO2 should be treated as named compliance references to screen when a CO2 refrigeration system is proposed. [1] At procurement stage, the practical question is not whether a salesperson can state that a product is “compliant.” The useful question is whether the supplier can identify the proposed system scope, the documents it will provide, and the assumptions or deviations that the project engineering team must evaluate.
Buyers should also preserve the distinction between a standard, a project specification, an engineering review, and an authority decision:
- ASHRAE 15 and IIAR CO2: named references to include in the CO2 system compliance screen. [1]
- Project specification: the purchaser’s document defining required supplier information, interfaces, exclusions, and review gates.
- Project-specific engineering: the technical work needed to apply the relevant requirements to the actual installation and configuration.
- Jurisdictional and local review: the project-location process that must be confirmed for the individual installation.
This guide does not interpret clauses from ASHRAE 15 or IIAR CO2, determine which edition a jurisdiction has adopted, or establish that either reference is the only requirement for a given project. The applicable requirement can depend on installation location, system configuration, and project scope.
Pre-RFQ CO2 refrigeration compliance-screening flow
- Confirm system scope: Record whether the proposed refrigeration-system scope uses CO2.
- Confirm project location: Identify the installation location and initiate confirmation of the applicable local code pathway.
- Screen named references: Enter ASHRAE 15 and IIAR CO2 in the project compliance register for the proposed CO2 system. [1]
- Allocate documentation: Identify who supplies package information and who performs project-specific engineering and installation compliance review.
- Record assumptions and open decisions: Require the supplier to identify scope limits, assumptions, and exceptions rather than leaving them implicit.
- Handover for detailed review: Refer unresolved design, installation, and local-approval questions to qualified project engineering and the appropriate local review process.
This flow is deliberately sequenced. A supplier should not be expected to resolve an undefined project jurisdiction or an undefined installation boundary. Conversely, the project team should not defer all compliance questions until equipment arrives on site.
CO2 Refrigeration Compliance Screening Matrix
| Screening field | Entry to make | Status options |
|---|---|---|
| Proposed system | Identify the proposed CO2 refrigeration-system package and included scope. | Confirmed / Open |
| Project location | Record the intended installation location and responsible party for local review. | Confirmed / Open |
| Application | State the commercial refrigeration or cold-room project application. | Defined / Open |
| ASHRAE 15 screening | Record that ASHRAE 15 is included in the CO2 compliance-reference screen. [1] | Included / Escalate |
| IIAR CO2 screening | Record that IIAR CO2 is included in the CO2 compliance-reference screen. [1] | Included / Escalate |
| Documentation owner | Name the party responsible for supplier package documents and the party responsible for project-specific review. | Assigned / Unassigned |
| Open project decision | List unresolved assumptions, exclusions, or local review questions. | Closed / Open |
The matrix is a control tool, not evidence of approval. Its value is that it makes missing inputs visible before a purchase order or detailed design decision creates avoidable ambiguity.
Supplier documentation request structure
Request documentation that allows the project team to understand the offered scope and route it for detailed review. Do not ask a supplier to make an unlimited, unqualified claim of project compliance where the installation basis has not yet been defined.
| Requested item | Purpose in prequalification | Buyer review question |
|---|---|---|
| System description | Defines the proposed package boundary and confirms whether CO2 is used. | Is the offered scope sufficiently clear for the compliance screen? |
| Project-specific compliance statement | Requires the supplier to state the basis, assumptions, and limits of any compliance-related statement. | Does the statement identify what is within supplier scope and what requires project review? |
| Applicable-document register | Creates a visible list of documents and references associated with the offer. | Are ASHRAE 15 and IIAR CO2 included in the CO2 screening record? [1] |
| Responsible engineering party | Prevents a gap between equipment supply and project-specific engineering. | Who performs the detailed engineering and installation compliance review? |
| Open deviations and assumptions | Prevents hidden exclusions from being mistaken for accepted project conditions. | Which items need resolution before award or detailed design? |
A document request is not a substitute for technical evaluation. It is a way to make evaluation possible. Buyers should avoid representing that certificates, test reports, listings, or approvals exist unless they have been separately requested, received, and evaluated for the actual project scope.
Project handover to detailed engineering and local review
Once the RFQ screen is complete, the project should transfer a concise compliance record to the responsible engineering and local-review functions. The handover record should identify the CO2 system scope, installation location, ASHRAE 15 and IIAR CO2 screening status, supplier-provided documents, assigned responsibilities, and unresolved decisions. [1]
Detailed design, installation, testing, and acceptance requirements must be confirmed for the individual project. This includes matters excluded from this guide, such as safety-relief, ventilation, detection, electrical, piping, controls, refrigerant charge, and testing design. A procurement record can support that work, but it cannot replace it.
Buyer action: Use the matrix and checklist in this guide to structure a technical RFQ and compare supplier responses on a consistent basis. Before award, ensure that the project has assigned responsibility for detailed engineering and confirmed the applicable local pathway for the installation.
Scope and limitations
This resource is an early procurement-screening aid for commercial refrigeration and cold-room projects in a United States code context. It is not project-specific engineering advice, a clause-by-clause code interpretation, jurisdiction-specific permit advice, or authority approval. The source context is the 2024 International Mechanical Code record; no claim is made that every jurisdiction adopts the same edition or applies identical requirements. [1]
References
- [1] International Code Council. 2024 International Mechanical Code, Chapter 11: Refrigeration. 2024 edition. https://codes.iccsafe.org/content/IMC2024P1/chapter-11-refrigeration. Accessed November 7, 2026.
Export this report as a PDF document for offline reading and sharing.