Understanding IBC Tote UN Ratings and Certifications

If you transport or store hazardous materials in IBC totes, understanding the UN (United Nations) rating system is not optional. It is a legal requirement. The UN marking stamped on every certified IBC tote is a coded specification that tells you exactly what the container is designed to carry, how dangerous those contents can be, and when the certification expires. This article decodes the entire system so you can read any IBC label plate with confidence.

Why UN Ratings Exist

The UN rating system for packaging, including IBC totes, was established by the United Nations Committee of Experts on the Transport of Dangerous Goods. The goal is to create a globally harmonized standard that ensures containers used to transport hazardous materials are designed, tested, and manufactured to safely contain those materials under normal transport conditions. In the United States, the Department of Transportation (DOT) adopts and enforces these standards through Title 49 of the Code of Federal Regulations (49 CFR).

Every IBC tote intended for hazardous material transport must pass a series of performance tests before receiving its UN certification. The tests simulate real-world conditions including drops, stacking loads, internal pressure, and vibration. Only IBCs that pass all required tests receive the UN marking.

Reading the UN Marking

The UN marking is permanently stamped or printed on a metal plate affixed to the IBC cage. A typical marking looks like this:

UN 31HA1/Y/08 21/USA/SCHTZ/10HZ463

Let us decode each element:

UN Symbol

The letters "UN" or the UN packaging symbol (a circle with lowercase "u" over "n") at the beginning indicates that this is a United Nations certified container. This symbol is legally protected and may only appear on packaging that has been tested and certified by an authorized testing laboratory.

IBC Type Code: 31HA1

This code identifies the specific type of IBC construction:

31 — Rigid IBC. The first two digits identify the packaging category. "31" means a rigid IBC designed for liquids. Other codes include "11" for rigid IBCs for solids, "21" for flexible IBCs, and "13" for rigid IBCs for solids loaded or discharged by pressure.

H — The material code. "H" denotes a plastic inner receptacle with structural equipment (the steel cage). Other material codes include "A" for steel, "B" for aluminum, "C" for natural wood, "D" for plywood, "F" for reconstituted wood, "G" for fiberboard, "H" for plastic, and "N" for other metals.

A1 — The sub-type. "A" with a number further specifies the construction. For type 31H, "A1" indicates a rigid plastic IBC with a structural frame (cage), fitted with equipment for handling and stacking. "A2" would indicate a freestanding rigid plastic IBC without structural equipment.

Packing Group: Y

This single letter is critically important. It indicates the maximum hazard level the IBC is certified to contain:

X — Approved for Packing Groups I, II, and III. This is the highest rating. Packing Group I materials present the greatest danger (high toxicity, high flammability, strong corrosives). An X-rated IBC has passed the most stringent testing, including higher drop heights and higher internal pressure tests. These IBCs are tested with a liquid of specific gravity up to 1.8.

Y — Approved for Packing Groups II and III. The most common rating. Packing Group II materials present moderate danger. Y-rated IBCs are tested with a liquid of specific gravity up to 1.4. This covers the vast majority of industrial chemicals transported by IBC.

Z — Approved for Packing Group III only. Packing Group III materials present the least danger among hazardous materials. Z-rated IBCs are tested with a liquid of specific gravity up to 1.2. Suitable for mildly hazardous or low-risk materials.

The packing group of the material you need to transport must be equal to or less hazardous than the IBC's rating. You can always use a higher-rated IBC for a lower packing group (use an X-rated IBC for PG III material), but never the reverse (never use a Z-rated IBC for PG II material).

Date of Manufacture: 08 21

The two-digit month and two-digit year of manufacture. In this example, "08 21" means August 2021. This date is crucial because UN certification for IBC totes is valid for a limited period. For rigid plastic IBCs (type 31H), the service life is typically 5 years from the date of manufacture for hazardous material transport. After this date, the IBC may still be perfectly functional but is no longer legally certified for regulated hazmat shipment. It can still be used for non-hazardous materials indefinitely.

Country of Approval: USA

The country that authorized the design type testing. "USA" indicates the IBC design was tested and approved by a DOT-authorized testing laboratory in the United States. IBCs tested in other countries carry their respective country code (D for Germany, F for France, CN for China, etc.). Under international agreements, UN certifications from one country are generally recognized by others, though some countries require additional national approvals.

Manufacturer and Serial Number

The remaining characters identify the manufacturer (in this example, "SCHTZ" for Schutz, a major global IBC manufacturer) and a unique serial or production lot number. This information allows traceability back to the specific production run, which is important for quality control and recall purposes. Major IBC manufacturers include Schutz, Mauser, Greif, Werit, and Thielmann.

Performance Tests Required for Certification

To receive a UN marking, IBC totes must pass these standardized performance tests as defined in the UN Model Regulations:

Bottom Lift Test: The filled IBC is lifted by the base (simulating forklift handling) and held for 5 minutes. No permanent deformation or leakage is permitted.

Top Lift Test: The filled IBC is lifted from the top frame. It must support twice its maximum gross weight for 5 minutes without failure.

Stacking Test: The filled IBC must support a superimposed load equal to the maximum stacking weight for 28 days without leakage, permanent deformation, or reduction of fill opening clearance.

Leakproofness Test: The IBC is pressurized with air to 20 kPa (2.9 psi) for 15 minutes. No air leakage is permitted.

Hydraulic Pressure Test: The IBC is filled with water and subjected to internal pressure. The test pressure varies by packing group: 75 kPa for PG III (Z), 100 kPa for PG II (Y), and 250 kPa for PG I (X). No leakage is permitted.

Drop Test: The filled IBC is dropped from a specified height onto each bottom edge, flat on the bottom, and on the top. Heights vary by packing group. No leakage is permitted after the drop.

Vibration Test: The filled IBC is subjected to vibration testing simulating road transport conditions for one hour. No leakage or permanent deformation is permitted.

Recertification and Reuse for Hazmat

After the initial 5-year certification period, a rigid plastic IBC may be requalified for another 2.5 years of hazardous material service if it passes a reduced set of inspections and tests (typically leakproofness and visual inspection). This requalification must be performed by an authorized facility. Not all used IBC dealers offer requalification services.

Reconditioned IBCs (new bottle in a refurbished cage) may receive a new UN certification if the reconditioning is performed by a DOT-authorized reconditioner and the resulting IBC passes the required performance tests. The new marking will indicate the reconditioning date and facility.

Practical Implications for Buyers

If you are buying used IBC totes and plan to transport hazardous materials, always verify that the UN certification date is within the valid service life (5 years, or 7.5 years if requalified). Check that the packing group rating matches or exceeds your material's packing group. Ensure the marking plate is present, legible, and permanently attached to the cage.

If you are buying used IBCs for non-hazardous applications (water storage, non-hazmat chemicals, agricultural use), the UN certification status is less critical, but the marking still provides useful information about the IBC's age, manufacturer, and construction type.

Need help determining the right UN rating for your application? Contact IBC Minneapolis and our team will help you select properly rated IBCs from our inventory.