IBCs Under 49 CFR: A Plain-English Guide

What the markings on the cage actually say

Most U.S. IBCs carry a UN marking that looks like UN31HA1/Y/[date]/[country code]/[manufacturer ID]. The 31 means rigid plastics IBC; HA1 means permitted for Packing Groups II and III hazardous liquids; Y is the packing group; the date is manufacture date. There are several variants — the rule of thumb is that if your tank carries a UN31HA1/Y stamp from a manufacturer code you can verify, you can legally ship most Packing-Group-II/III liquids in it.

Why requalification matters

49 CFR § 178.801 requires IBCs intended for continued hazmat duty to be requalified on a defined cycle — typically 2.5 years for retest and 5 years for full re-certification. A reconditioned IBC sold for hazmat service has been through that requalification process at our facility, and we provide the documentation.

The retest stamp on the cage is the buyer's indicator. If you receive a tank for hazmat duty and the stamp is older than 2.5 years from your fill date, the tank is not legally usable for that service until requalified.

What buyers should ask

• What grade is this tank? (See our grading system.)
• If hazmat-eligible: when was the last requalification?
• What was in the tank before this fill, and is the contents history documented?
• Are the markings on the cage still legible and current?

When the regulation does NOT apply

A surprising amount of confusion comes from buyers asking 49 CFR questions about non-hazmat applications. Water storage, rainwater capture, certain ag inputs, many cleaning concentrates — none of these are regulated under 49 CFR. The cage may still carry the stamp from a prior life, but the regulatory burden on you as the shipper is much narrower.