EPA 608 Type III certification
A low-pressure appliance uses a refrigerant with a liquid phase saturation pressure below 45 psia at 104 °F.
What the rule says
"Persons who maintain, service, repair, or dispose of low-pressure appliances must be certified as Type III technicians."
Equipment this applies to
- Centrifugal chillers using R-11, R-123 or R-245fa. Those refrigerants sit below 45 psia at 104 °F, which is the low-pressure definition.
Also typically: Centrifugal chillers using R-11, R-123 or R-245fa · Large building and campus chiller plants
The pressure class behind it
| Class | Rule | Example refrigerants |
|---|---|---|
| Low-pressure | Liquid phase saturation pressure below 45 psia at 104 °F. | R-11, R-123, R-113, R-245fa |
The smallest population of technicians, and the systems run in a vacuum, which is why the evacuation and leak-detection material differs from the other types.
What the exam actually covers
Every path includes the Core section, which is 54 distinct topics in our bank across 93 questions. Then you add the section for your type. The breakdown below is the topic distribution of our own question bank, mapped to the published outline, so it shows where the weight of the material sits rather than guessing.
Core (Group I), 54 topics
Montreal caa 5Odp chlorine 5Ozone chemistry 4Phaseout schedule 4Pt charts 4Superheat subcool 4Vc cycle states 4Certification types 3Industry outlook 3Sales restriction 3Three rs definitions 3608 vs 609 2Evacuation dehydration 2Non condensables 2Ozone effects 2Recordkeeping 2Vc cycle components 2Venting exceptions 2Venting prohibition 2Apprentice supervision 1Disposal 1Evacuation purpose 1Evacuation vacuum measurement 1Exempt substitutes 1
Type III: Low-Pressure Systems, 24 topics
Safety 9Recovery procedure 8Disposal reclamation 8Evacuation levels 7Leak repair pressurizing 7Charging 4Leak rates 4Air infiltration 3Below atmospheric 3Heating refrigerant 3Evacuation vacuum 2Leak check pressure 2Purge units 2Rupture disc 2Water boxes 2Charging freeze protection 1Leak rate triggers 1Lp definition 1Lp refrigerants 1Modern refrigerants 1Phaseout supply 1Pressure classes 1Recovery freeze protection 1Scope 1
Why Type III material feels different
Low-pressure systems run below atmospheric pressure, which changes the physics the exam asks about. Air and moisture leak into the machine rather than refrigerant leaking out, so purge units, leak detection and the evacuation levels all work differently from the high-pressure equipment most technicians meet first. That is why 24 of our topics for this section are specific to it.
Practice it
Drill the Type III section free, and anything you miss goes into your notebook so you can come back to exactly the questions that caught you out.
10 questions · 12 minutes · pass at 70%
Questions are sampled to mirror the official domain weighting. The timer starts when you begin; you can flag questions and return to them before submitting.
Before you book
- Where to take the exam: all 87 EPA-approved organisations, 15 of which test remotely or online.
- What score you actually need, and why the widely quoted 72 percent is not what the regulation says.
- Still not sure which type? The chooser works it out from the equipment you service.
One thing that can change the answer
The regulation says plainly that "persons who dispose of small appliances, MVACs, and MVAC-like appliances are not required to be certified." Disposal of medium, high, very high or low-pressure appliances still requires the matching type. So the same person can need certification to service a unit and not need it to scrap a different one.
Sources
Certification types and what each authorises: 40 CFR 82.161. Equipment and pressure-class definitions: 40 CFR 82.152. Exam structure and passing scores: 40 CFR Part 82, Subpart F, Appendix D. Topic counts are from this site's own question bank, mapped to the published outline. Verified 2026-08-15.