Resources
A directory of primary sources for cargo tank work. Every link points to the authority’s own current copy — nothing here is republished, because a copy goes stale and the original doesn’t.
Testing & Inspection
eCFR
49 CFR 396.17 — Periodic Inspection (Annual Vehicle Inspection)
The annual vehicle inspection for every truck, tractor and trailer, tank trailers included. It’s separate from the cargo tank tests.
eCFR
49 CFR 180.407 — Test and Inspection of Specification Cargo Tanks
The rule behind every periodic cargo tank test and inspection.
eCFR
49 CFR 180.415 — Test and Inspection Markings
How test and inspection markings go on the tank.
Shell & Structure
eCFR
49 CFR 180.413 — Repair, Modification, Stretching, Rebarrelling, or Mounting
Who may repair or modify a specification cargo tank, and under what rules.
Shop Safety
OSHA
OSHA 1910.146 — Permit-Required Confined Spaces
OSHA's rule for permit-required confined spaces. Open it before anyone goes inside a tank.
OSHA
OSHA 1910.147 — Control of Hazardous Energy (Lockout/Tagout)
OSHA's lockout/tagout rule, for anything that can move or energize while someone is working on it.
OSHA
OSHA 1910.252 — Welding, Cutting and Brazing: General Requirements
OSHA's general requirements for welding, cutting and brazing, including hot work on containers.
Facility & Registration
FMCSA
Cargo Tank Facility Search
Look up whether a facility is registered and what it's registered for.
FMCSA
Cargo Tank Registration and Resources
FMCSA's hub for cargo tank facility registration — portal, registration aid, and facility search in one place.
FMCSA
USDOT Company Search
Look up a carrier's legal name and USDOT record — useful when the name on the truck isn't the name on the paperwork.
Specs & Interpretations
PHMSA
PHMSA — Letters of Interpretation
How PHMSA has answered questions about the hazmat rules, and how to request your own letter.
eCFR
49 CFR 178.338 — Specification MC-338 Insulated Cargo Tank
Construction spec for MC-338 tanks: cryogenic liquids.
eCFR
49 CFR 178.337 — Specification MC 331 Cargo Tank
Construction spec for MC 331 tanks: compressed gases, such as propane.
eCFR
49 CFR 178.348 — Specification DOT 412 Cargo Tank
Construction spec for DOT 412 tanks: corrosives, such as acids.
eCFR
49 CFR 178.347 — Specification DOT 407 Cargo Tank
Construction spec for DOT 407 tanks: solvents and other chemicals.
eCFR
49 CFR 178.346 — Specification DOT 406 Cargo Tank
Construction spec for DOT 406 tanks: gasoline, diesel and other flammable liquids.
FMCSA
Top Cargo Tank Manufacturing Violations
What gets written up most often at cargo tank manufacturers and assemblers.
FMCSA
Top Cargo Tank Facility Violations
What gets written up most often at registered cargo tank facilities.
PHMSA
PHMSA — Hazardous Materials Information Center
Ask PHMSA a hazmat-regulations question directly, by phone or email.