Comfort Cooling, Commercial Refrigeration, or Industrial Process? The § 84.102 Category That Sets Your Leak-Rate Threshold

Before you can tell whether a leak rate is a problem, you have to know what number it's being compared against. And that number isn't a property of the refrigerant, the charge size, or the building. It's a property of the appliance category — one of three buckets defined in 40 CFR § 84.102 — and the category is the very first thing you decide about a piece of equipment when you set it up in a log, a spreadsheet, or a calculator.

Get it right and the rest of the rule runs on rails. Get it wrong and every leak rate on that unit is compared to the wrong threshold — quietly, for as long as the record exists.

This is the reference for making that call. The three definitions verbatim from the current rule text, where the equipment you actually service lands, the handful of edge cases (chillers, ice machines, mixed-use, reefers), and everything else in § 84.106 that keys off the same choice.

The Three Thresholds — and the Catch-All

Start with the numbers, because they're the reason the category matters. Under § 84.106(c)(2), the leak rate that triggers repair obligations is:

Read (iii) carefully, because its wording is the single most useful thing in this post. The 10% bucket is the default. An appliance doesn't have to qualify as comfort cooling to get the 10% threshold — it gets 10% unless it fits the definition of commercial refrigeration or industrial process refrigeration. Comfort cooling, refrigerated transport, and "other" all land in the same place. So the classification question is really only two questions: does this appliance meet the commercial refrigeration definition? and does it meet the industrial process refrigeration definition? If the answer to both is no, the threshold is 10% and it does not matter what else you call it.

That framing matters for the leak-rate math because the two higher buckets are privileges you have to earn by fitting a definition — not labels you can pick because they're more forgiving.

The Definitions, Verbatim

All three terms are defined in § 84.102. Here is the current text — pulled from the eCFR as it stands today, not paraphrased.

Comfort cooling — 10%

The test is the purpose: air conditioning for people in a building. The definition names the equipment most small contractors service all day — packaged rooftop units, commercial split systems, heat pumps — and it names chillers, which is where a lot of misfiling starts (more on that below).

One thing to keep straight: the definition of comfort cooling includes residential systems, but § 84.106(a)(3)(ii) then exempts appliances "used for the residential and light commercial air conditioning and heat pump subsector" from the leak-repair rule entirely. So covered comfort cooling is the part of this definition that sits outside that carve-out — commercial buildings, not houses. We drew that line in detail here; this post assumes the appliance is already past it.

Commercial refrigeration — 20%

This one is defined by sector, not by equipment type or by the word "commercial." A refrigeration appliance in a supermarket, convenience store, restaurant, food-service operation, or a cold-storage warehouse holding perishables is commercial refrigeration. That's the definition that catches walk-ins, cases, and racks — but notice what it does not say. It doesn't say "any refrigeration appliance owned by a business." A refrigeration appliance that isn't in the retail-food or cold-storage-warehouse subsector doesn't get 20% by being non-residential; absent an IPR fit, it falls back to the 10% catch-all.

Industrial process refrigeration — 30%

Three things to pull out of that. First, the words "complex customized" and "directly linked to the processes" — IPR is refrigeration that is part of making something, not refrigeration that happens to be located at a factory. Second, the definition names its outliers: industrial ice machines, power-generation cooling, and ice rinks are IPR by name, even though none of them is a chemical plant. Third, the 50 percent rule for mixed-use appliances — the only place in the three definitions where the rule tells you how to break a tie.

Where the Common Equipment Actually Lands

Applying the definitions to the equipment a small shop or a building owner actually has:

A few of these deserve a closer look.

The chiller problem

"Chiller" is the word most likely to be misfiled, because contractors hear it and think "industrial." The rule doesn't. A chiller whose job is conditioning air for people — the water-cooled centrifugal in a hospital basement, the air-cooled scroll on an office building — is comfort cooling at 10%, because that's the purpose the comfort cooling definition describes and "chillers" is the first item in its equipment list. The same chiller model cooling a process fluid on a plant floor is IPR at 30%. It's the application, not the machine, and a chiller filed as IPR when it's really comfort cooling has a threshold three times looser than the law gives it. That's the classic misfile, and it's an easy one to make on the R-134a calculator if you pick the category by the equipment name.

Ice machines: "industrial" is doing real work

The IPR definition says industrial ice machines. The under-counter cuber behind a restaurant bar is a retail-food appliance — and, at a few pounds of charge, almost never over the 15-lb line in the first place. Don't let the phrase "ice machine" pull small commercial equipment into the 30% bucket.

Mixed use: the 50 percent test

If one appliance does both process cooling and something else — say a chiller loop that serves a production process and the office space next to it — the rule gives you the tiebreaker: it's IPR "if 50 percent or more of its operating capacity is used for industrial process refrigeration." Document the split. This is the one place where your category determination should carry a number.

Reefers and the rule that hasn't landed

Refrigerated transport isn't separately defined in § 84.102, but § 84.106(c)(2)(iii) names "refrigerated transport appliances" in the 10% bucket — so a covered reefer is judged at 10%, same as comfort cooling. Two honest caveats. First, whether a given trailer or container unit is covered runs through the same 15-pound / GWP > 53 applicability test as everything else. Second, EPA published a proposed rule on May 26, 2026 (91 FR 30532) that would remove road and intermodal-container transport refrigeration units from the leak-repair requirements entirely. As of this writing it is still a proposal — the Federal Register lists it as a proposed rule with no final action — so today's rule is unchanged: 10%, covered. If that changes, we'll write it up.

The Category Decides More Than the Threshold

If the leak-rate threshold were the only thing riding on the category, a misfile would be one wrong comparison. It isn't. The same classification decides several other clocks and duties in § 84.106, all of them keyed to "industrial process refrigeration" or "commercial refrigeration" by name:

• The repair clock, § 84.106(d). Leaks must be identified and repaired "within 30 days (or 120 days if an industrial process shutdown is required)." The 120-day alternative exists only for IPR appliances, and only when the process genuinely has to be shut down to make the repair — the rest of the repair workflow is the same. Comfort cooling and commercial refrigeration get 30 days, full stop.
• Extensions, § 84.106(f). The parts-availability extension caps at 180 days from the exceedance — "or 270 days if an industrial process shutdown is required." Same category, same asymmetry.
• The post-repair inspection schedule, § 84.106(g)(1). Quarterly inspections after an exceedance apply only to "commercial refrigeration and industrial process refrigeration appliances with a full charge of 500 or more pounds." Comfort cooling and everything else is annual at any charge size. A 90-lb rooftop unit and a 900-lb chiller serving the same building are both annual; a 500-lb rack is quarterly.
• Automatic leak detection, § 84.108. The ALD mandate at 1,500 pounds or more applies to appliances "used for industrial process refrigeration or commercial refrigeration." A 1,500-lb comfort cooling chiller isn't in it.
• "Custom-built," § 84.102. The definition that unlocks certain retrofit/retirement timing is written for "industrial process refrigeration equipment or any of its components" — it doesn't exist for the other two categories.

Notice the pattern: everything the rule gives IPR — the 30% threshold, the 120-day clock, the 270-day extension cap, custom-built timing — it gives because IPR is complex, process-linked equipment that can't be shut down or resourced quickly. Filing a comfort-cooling chiller as IPR doesn't just loosen the threshold; it hands that appliance a set of allowances the rule never intended for it. An inspector reading a 120-day repair record on a building chiller isn't going to see a paperwork slip. They're going to see a threshold, a deadline, and an inspection schedule that are all wrong in the same direction.

What a Misfile Actually Does to the Record

Take the most ordinary service call there is: a 7.5-ton rooftop unit with an 18-lb full charge of R-410A takes 3 pounds on the first addition of the year. Annualized on the first-calculation rule, that's 16.7%.

Filed correctly as comfort cooling, that unit just tripped the 10% threshold: a 30-day repair clock starts, an initial and follow-up verification test are owed, and an annual inspection schedule follows. Misfiled as commercial refrigeration — because the tenant is a restaurant and everything on the ticket got the same category — the same 16.7% reads as under 20%, no repair action is created, and no clock starts. Nothing in the record looks wrong. The rate was calculated with an approved method, the addition was logged, the ticket has all eight § 84.106(l)(2) fields. It's just being judged against a threshold that doesn't apply, and the 30-day deadline the rule started on the day of that addition passes without anyone knowing it existed.

The reverse misfile is less dangerous and more expensive: a walk-in filed as comfort cooling gets held to 10% instead of 20% and generates repair actions the rule doesn't require. That costs you labor and customer patience, not a violation — but it also teaches the shop to distrust the numbers, which is how real exceedances start getting waved off.

The leak-rate math can be perfect and the record still wrong. The category is the one input that changes what "over" means.

Write the Determination Down

The recordkeeping paragraph, § 84.106(l), doesn't list "appliance category" as a required field — the per-appliance file under (l)(1) asks for the full charge, its method, revisions, location, and installation date, and the service record under (l)(2) asks for the leak rate and the method used to determine it. But the leak rate is only meaningful against a threshold, and the threshold comes from the category. If your file shows a 16.7% leak rate and no repair action, the first question is "what did you compare it to, and why?" A one-line category determination on the appliance record — with the reason, and the capacity split for anything mixed-use — is how you answer that in five seconds instead of an afternoon.

Two more habits that keep this clean:

Classify per appliance, not per site. A restaurant has commercial refrigeration in the kitchen and comfort cooling on the roof. A plant has IPR on the process line and comfort cooling in the front office. The building's business tells you what to look for; it doesn't set the category of every unit inside it. And remember that under § 84.102, an appliance with multiple independent refrigerant circuits is counted as a separate appliance per circuit — each one gets its own category and its own full charge.

Classify by purpose, then check the named list. Ask what the appliance is for — people, food, or process — and then check whether the definition names it outright (rooftop units, chillers, ice rinks, industrial ice machines). When purpose and name seem to disagree, purpose wins for chillers (the definition puts them under comfort cooling because of the purpose) and the named list wins for the IPR outliers (ice rinks are IPR because the rule says so).

The Ten-Second Version

1. Is it in the retail food or cold storage warehouse subsector? Supermarket, convenience store, restaurant, food service, or a warehouse holding perishables → commercial refrigeration, 20%.
2. Is it complex, customized, and directly linked to a manufacturing/chemical/pharma/petrochemical process — or an ice rink, industrial ice machine, or power-generation cooling? → Industrial process refrigeration, 30%. Mixed use: 50% or more of capacity on the process.
3. Neither? → 10%. Comfort cooling, transport, or "other" — the threshold is the same. Then confirm it isn't in the residential/light-commercial AC/HP subsector, which is exempt outright.

Make that call once, at setup, in writing. Every leak rate the appliance ever generates is judged by it.