To determine the minimum drum marking for the product you are shipping you must, at a minimum, know the following information about the hazardous material:
First, determine the Packing Group of the material. Hazardous materials are categorized in Packing Groups ranging from I - III, with I being the most hazardous. For solids, drums are authorized to carry a specific gross mass in kilograms (Kg), so you must know the mass (i.e., the weight of the material) you will be shipping. To ship liquids you must know the vapor pressure at either 50 or 55 degrees Celsius and the specific gravity.
The worksheet below may assist you in determining the marking you require.
Shippers of hazardous materials that use non-bulk or intermediate bulk packaging are required to use UN marked packaging.
Reconditioners use a durable mark (e.g., stenciling) to indicate the UN standard the drum meets. The full durable mark (minus thickness) from the reconditioner is generally found on the side of a drum. If your non-bulk container has been or "remanufactured" (e.g., converted from a closed head to an open head drum), the remanufacturer permanently marks (e.g., embosses) the side of the drum. If a tight head drum has been remanufactured, a UN durable mark may be placed on the side.
DOT prescribes specific minimum thicknesses for steel drums that are reused for transporting hazardous materials. Steel 55-gallon drums must be at least 0.92 millimeters thick throughout, or have a shell and head thickness of 0.82 mm and 1.11 mm, respectively. Steel drums that do not meet these minimum thickness requirements may not be reused to transport DOT regulated materials. To promote reuse and prevent empty drum disposition problems, RIPA recommends that users order 55-gallon steel drums, which meet or exceed the DOT minimum thickness requirements.
If you order the old 20/18 style drum, to ensure your containers meet the minimum thickness requirements, they must be marked "1.2/0.9/1.2". Containers that are marked in other ways may not meet the DOT minimum thickness requirements. To maximize the value of your drum see the table below that outlines drum desirability.
Item Usually Preferred Usually Less Preferred Manufacturing Performance Specifications UN-marked and tested to Packing Group I or II UN-marked to Packing Group III and non-UN Thickness Nominal 1.0 mm or 1.2/0.9/1.2 mm Less than nominal 1.0 mm or 1.2/0.9/1.2 mm
RIPA RecommendationThe steel thickness of your drum should meet or exceed the minimum thickness requirements authorized by the U.S. DOT. To ensure your drums meet these requirements, the drum should be at least 0.92 mm throughout, or have 1.11 mm heads and 0.82 mm body. Drum which do not meet these minimums may not be reused for hazardous materials transportation after reconditioning. (49 CFR 173.28)
Nominal drum marks that correspond to the DOT minimum thickness requirements are 1.0, or 1.2/0.9/1.2.
Fittings, Plugs, Flanges
RIPA RecommendationPlugs, flanges and other closure components should, when feasible, comply with ANSI specifications. Plugs on the drum body, agitators, etc. reduce the reuse value of an empty drum and, therefore, should only be ordered when necessary.
Paint and LiningsLining Paint
RIPA RecommendationDrum linings can be difficult to remove during the reconditioning process, adding processing costs to an empty drum. Unless required to ensure product integrity, use of linings should be avoided.
DOT requires drum manufacturers and reconditioners to provide closure instructions to drum purchasers. Be sure that you obtain these instructions and they are followed carefully.
If you ship many different products that require different UN markings, it is a good idea to examine the possibility of stocking drums bearing only 1 or 2 different markings. Since most steel drums appear the same, except for the marking, they can be easily confused. To minimize the chance of an accidental mix-up, it is often best to stock fewer variations of drum markings. If a product is shipped in a container that is "under-marked" or marked below the required performance level it is a violation of DOT rules. However, it is legal to ship hazardous materials in a container marked to higher performance level than required. RIPA, therefore, suggests shippers consider "grouping" products and purchase drums at levels high enough to carry many lower hazard products.