For a U.S. mini scuba cylinder service quote, start with the markings on the actual cylinder and ask which facility will perform any required DOT requalification. The U.S. Pipeline and Hazardous Materials Safety Administration (PHMSA) lets you look up a requalifier by location and see the cylinder specifications and testing methods its approval covers. That gives you a way to check the scope of a quote before you ship or drop off your equipment. PHMSA’s Cylinder Requalifiers page explains the lookup.
Check the facility doing the work
A dive shop can receive your cylinder and refer it elsewhere for requalification. Ask for the name, address and Requalifier Identification Number (RIN) of the facility that will actually do the work. Compare that location and the authorized cylinder specifications in the PHMSA listing. For work represented as complying with U.S. hazardous-materials requalification requirements, 49 CFR § 180.205(b) requires a current approval. The surrounding rule concerns authorized cylinder packaging in hazardous-materials transport. The facility should confirm whether and how the rule applies to your exact cylinder.
Ask for a quote that identifies the cylinder and the work
| Ask about | What the answer should identify |
|---|---|
| Cylinder identity | The manufacturer’s model and the actual specification or special-permit markings, if present. Send any serial-number photograph privately to the service provider. |
| Work and provider | The service being quoted, the facility and its relevant approval scope. Ask which inspections, if any, are separate from requalification. |
| Record at return | Which result and paperwork will identify your cylinder, and which markings apply if it passes. |
| Additional service | Whether a separate provider is needed for valve, regulator or breathing-air fill service. Ask what is included before comparing total cost. |
49 CFR § 180.213 describes requalification markings, generally including the date and the requalifier’s identifier, with format variations for particular cases. Ask the facility to explain the applicable marking and result. A prior mark records earlier work. Current acceptance and next steps still depend on the actual cylinder and the facility’s assessment.
Get product documentation before buying
If you are considering the TRIMIX T-500, ask TRIMIX for the markings and documents for the unit offered. Share them with the intended U.S. service provider before committing. The directory establishes what a provider is authorized to do. A product name, advertised size or photo cannot establish U.S. specification status or local service acceptance. Follow the applicable manufacturer instructions and use qualified support for inspection and breathing-air equipment.
U.S. federal references checked November 12, 2026. Provider approval and service scope can change.
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