Glossary — Definitions of Key Industry Terms and Acronyms



Bead — the outward steel curl at the top perimeter of an open head drum.

Bolt Ring — a closing device used to secure a cover to the body of an open head drum. This ring requires a bolt and a nut to secure the closure.

Buff — refers to the tan color of a lining. More important than the color of a lining, however are the properties that the linings exhibit in combination with materials that are placed in to the containers. We have a lot more information available on this and access to more comprehensive information through our suppliers.

Bulk Packaging — a packaging, other than a vessel or a barge, including a transport vehicle or freight container, in which hazardous materials are loaded with no intermediate form of containment and which has:

  • A maximum capacity greater than 450 L (119 gallons) as a receptacle for a liquid;
  • A maximum net mass greater than 400 kg (882 pounds) and a maximum capacity greater than 450 L (119 gallons) as a receptacle for a solid; or
  • A water capacity greater than 454 kg (1000 pounds) as a receptacle for a gas as defined in §173.115 of CFR49.

Bung — a threaded closure that is located in the head or body of a drum.

Bureau of Explosives — Bureau of Explosives (B of E) of the Association of American Railroads.

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C — Celsius or Centigrade.

Chime - bottom or top perimeter of the drum comprised of the edges of the combined thickness of the head and the body.

Code of Federal Regulations (CFR) — a codification of rules published in the Federal Register by the Executive Departments and Agencies of the Federal Government. The code is divided in to 50 Titles representing the broad areas subject to Federal Regulation.

Combination Packaging — a combination of packaging, for transport purposes, consisting of one or more inner packagings secured in a non-bulk outer packaging. It does not include a composite packaging.

Competent Authority — a national agency responsible under its national law for the control or regulation of a particular aspect of the transportation of hazardous materials (dangerous goods). The term Appropriate Authority, as used in the ICAO Technical Instructions (see § 171.7 of CFR49), has the same meaning as Competent Authority. For purposes of this subchapter, the Associate Administrator is the Competent Authority for the United States.

Composite Packaging — a packaging consisting of an outer packaging and an inner receptacle, so constructed that the inner receptacle and the outer packaging form an integral packaging. Once assembled it remains thereafter an integrated single unit; it is filled, stored, shipped and emptied as such.

Cover — a removable top head.

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DGSA — Dangerous Goods Safety Advisor is a person that accepts responsibility within an organization for ensuring that all hazardous materials are shipped in compliance with the prevailing regulations be they air, sea, rail or road.

DOD — U.S. Department of Defense.

DOT — U.S. Department of Transportation.

Drum — a flat-ended or convex-ended cylindrical packaging made of metal, fiberboard, plastic, plywood, or other suitable materials. This definition also includes packagings of other shapes made of metal or plastic (e.g., round taper-necked packagings or pail-shaped packagings) but does not include cylinders, jerricans, wooden barrels or bulk packagings.

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EPA — U.S. Environmental Protection Agency.

Exemption — a document issued under the authority of 49 U.S.C. 5117 by the Associate Administrator that authorizes a person to perform a function that is not otherwise authorized under subchapter C, or other regulations issued under 49 U.S.C. 5101-5127 (e.g., Federal Motor Carrier Safety Administration routing).

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Flange — the closure attachment that is permanently inserted into the drum and provides the receiving threads for a plug.

Freight Container — a reusable container having a volume of 64 cubic feet or more, designed and constructed to permit being lifted with its contents intact and intended primarily for containment of packages (in unit form) during transportation.

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Gallonage — according to the United States Department of Transportation, CFR Title 49, the actual capacity of a drum must be at least 4% greater than its rated capacity.

Gauge — a measure of thickness that we use as a reference for the thickness of the sheets of steel we use to produce steel containers. View our Gauge Chart.

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Hazard Class — the category of hazard assigned to a hazardous material under the definitional criteria of part 173 of CFR49 and the provisions of the §172.101 Table. A material may meet the defining criteria for more than one hazard class but is assigned to only one hazard class.

Hazardous Material — a substance or material, which has been determined by the Secretary of Transportation to be capable of posing an unreasonable risk to health, safety, and property when transported in commerce, and which has been so designated. The term includes hazardous substances, hazardous wastes, marine pollutants, and elevated temperature materials and materials designated as hazardous under the provisions of §172.101 of CFR49, and materials that meet the defining criteria for hazard classes and divisions in part 173 of CFR49.

Hazardous Waste — means any material that is subject to the Hazardous Waste Manifest Requirements of the U.S. Environmental Protection Agency specified in 40 CFR part 262.

Hazmat Employee — a person who is employed by a hazmat employer and who in the course of employment directly affects hazardous materials transportation safety. This term includes an owner-operator of a motor vehicle which transports hazardous materials in commerce. This term includes an individual, including a self-employed individual, employed by a hazmat employer who, during the course of employment:

  1. Loads, unloads, or handles hazardous materials;
  2. Manufactures, tests, reconditions, repairs, modifies, marks, or otherwise represents containers, drums, or packagings as qualified for use in the transportation of hazardous materials;
  3. Prepares hazardous materials for transportation;
  4. Is responsible for safety of transporting hazardous materials; or
  5. Operates a vehicle used to transport hazardous materials.

Head — refers to a top and / or bottom of a drum.

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IAEA — International Atomic Energy Agency.

IATA — International Air Transport Association.

ICAO — International Civil Aviation Organization.

IMO — International Maritime Organization.

Inner Packaging — a packaging for which an outer packaging is required for transport. It does not include the inner receptacle of a composite packaging.

Intermediate Packaging — a packaging which encloses an inner packaging or article and is itself enclosed in an outer packaging.

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Lever Lock Ring — a closure device used to secure a cover to the body of an open head drum. Operated by an expanding lever that is built into the ring, this style also has a fixed sealing device.

Limited Quantity — the maximum amount of a hazardous material for which there is a specific labeling or packaging exception.

Lining — protective coatings applied to the inside of steel containers to protect the product being placed in the containers from becoming contaminated, whether from the steel or other sources. They also prevent the material in the containers from coming into contact with the steel, where it might corrode or adversely affect the quality of the container.

Liquid — a material, other than an elevated temperature material, with a melting point or initial melting point of 20 °C (68 °F) or lower at a standard pressure of 101.3 kPa (14.7 psi). A viscous material for which a specific melting point cannot be determined must be subjected to the procedures specified in ASTM D 4359 "Standard Test Method for Determining Whether a Material is Liquid or Solid" (see § 171.7 of CFR49).

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Mode — any of the following transportation methods; rail, highway, air, or water.

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N.O.S. — not otherwise specified.

NPT — an American Standard taper pipe thread conforming to requirements of Federal Standard H28, part II, section VII. See §171.7 of CFR49.

NRC (non-reusable container) — a packaging (container) whose reuse is restricted in accordance with the provisions of §173.28 of CFR49.

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Outer Packaging — the outermost enclosure of a composite or combination packaging together with any absorbent materials, cushioning and any other components necessary to contain and protect inner receptacles or inner packagings.

Overpack — except as provided in subpart K of part 178 of CFR49, means an enclosure that is used by a single consignor to provide protection or convenience in handling of a package or to consolidate two or more packages. Overpack does not include a transport vehicle, freight container, or aircraft unit load device. Examples of overpacks are one or more packages:

  1. Placed or stacked onto a load board such as a pallet and secured by strapping, shrink wrapping, stretch wrapping, or other suitable means; or
  2. Placed in a protective outer packaging such as a box or crate.

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Packaging — a receptacle and any other components or materials necessary for the receptacle to perform its containment function in conformance with the minimum packing requirements of the Code of Federal Regulations. For radioactive materials packaging, see §173.403 of CFR49.

Packing Group — a grouping according to the degree of danger presented by hazardous materials. Packing Group I indicates great danger; Packing Group II, medium danger; Packing Group III, minor danger. See §172.101(f) of CFR49.

Plug — the removable closure that allows a drum to be filled or emptied.

POPS — Performance Oriented Packaging Standard - the regulations adopted by the US DOT and the UN in which packagings must meet specific testing criteria in order to be used for the transport of dangerous goods.

Psi — pounds per square inch.

Psig — pounds per square inch gauge.

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Radioactive Materials. See §173.403 of CFR49 for definitions relating to radioactive materials.

Residue — the hazardous material remaining in a packaging, including a tank car, after its contents have been unloaded to the maximum extent practical and before the packaging is either refilled or cleaned of hazardous material and purged to remove any hazardous vapors.

Rieke — a style of plug closure system used to secure contents in steel drums. The most commonly used Rieke style plugs are referred to as the 2" Plug and the ¾" Vent Plug. The Rieke style plug is easily recognized with an hexagonal plug that screws into an round flange that is secured to the drum. Closure Instructions must be followed to insure a UN compliant closure.

Rolling Ring — the hooped expansions that are located in the body of a drum that act as reinforcement rings to permit easy handling of the filled drums.

RSPA — Research and Special Programs Administration, U.S. Department of Transportation, Washington, DC 20590.

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Salvage Packaging (Salvage Drum) — a special packaging conforming to § 173.3 of CFR49 into which damaged, defective, non-compliant or leaking hazardous materials packages, or hazardous materials that have spilled or leaked, are placed for purposes of transport for recovery or disposal.

SDCC — the DOT manufacturing code designating Skolnik Industries, Inc. as a certified manufacturer of DOT drums and packagings.

Seam — point at which the flat steel sheet has been rolled and electrically welded to form a cylinder.

Single Packaging — a non-bulk packaging other than a combination packaging.

Solid — a material which is not a gas or a liquid.

Specification Packaging — a packaging conforming to one of the specifications or standards for packagings in part 178 or part 179 of CFR49.

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Torque — a measure of rotational force applied to an object. For steel containers, calibrated torque is required to close the fittings of a closed head and the bolt ring of an open head. Torque can be measured in ft-lbs., inch-lbs., or neuton-meters.

Title 49 — One of the 50 titles which represent the broad area's subject to Federal Regulation within the Code of Federal Register. Title 49 deals specifically with transportation and is revised annually.

Tri-Sure — A style of plug closure system used to secure contents in steel drums. The most commonly used Tri-Sure style plugs are referred to as the 2" Plug and the ¾" Vent Plug. The Tri-Sure style plug is easily recognized with a round plug that screws into an octagonal flange that is secured to the drum. Closure Instructions must be followed to insure a UN compliant closure.

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UFC — Uniform Freight Classification.

Ullage — the amount that a container (as a tank or cask) lacks of being full.

UN — United Nations.

UN Recommendations — the UN Recommendations on the Transport of Dangerous Goods.

UN Standard Packaging — a packaging conforming to standards in the UN Recommendations.

United States — a State of the United States, the District of Columbia, the Commonwealth of Puerto Rico, the Commonwealth of the Northern Mariana Islands, the Virgin Islands, American Samoa, Guam, or any other territory or possession of the United States designated by the Secretary.

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Viscous Liquid — a liquid material which has a measured viscosity in excess of 2500 centistokes at 25° C. (77° F.) when determined in accordance with the procedures specified in ASTM Method D 445-72 "Kinematic Viscosity of Transparent and Opaque Liquids (and the Calculation of Dynamic Viscosity)" or ASTM Method D 1200-70 "Viscosity of Paints, Varnishes, and Lacquers by Ford Viscosity Cup."

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Water, Weight of — 1 US Gallon – 8.35 lbs., 1 Imperial Gallon – 10 lbs.

Wooden Barrel — a packaging made of natural wood, of round cross-section, having convex walls, consisting of staves and heads and fitted with hoops.

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