Elevated temperature materials

Scope

Elevated temperature materials have special requirements under the hazardous materials regulations.

Regulatory citations

• 49 CFR 171.8 — Definitions and abbreviations
• 49 CFR 172.325 — Elevated temperature materials
• 49 CFR 173.247 — Bulk packaging for certain elevated temperature materials

Key definitions

• Bulk packaging: Other than vessels or barges, and including transport vehicles and freight containers, are packagings in which hazardous materials are loaded with no intermediate form of containment and which have:
  • A maximum capacity greater than 119 gallons (450 L) as a receptacle for a liquid;
  • A maximum net mass greater than 882 pounds (400 kg) and a maximum capacity greater than 119 gallons (450 L), as a receptacle for a solid; or
  • A water capacity greater than 1,000 pounds (454 kg), as a receptacle for a gas.
  A Large Packaging in which hazardous materials are loaded with an intermediate form of containment, such as one or more articles or inner packagings, is also a bulk packaging.
• Elevated temperature material: A material offered for transportation in a bulk packaging that meets one of the following criteria:
  • A liquid with a temperature at or above 100°C (212°F); or
  • A liquid with a flash point at or above 37.8°C (100°F) that is intentionally heated and transported at or above its flash point; or
  • A solid with a a temperature at or above 240°C (464°F).
• Residue: The hazardous material remaining in a packaging, including a tank car, after its contents have been unloaded to the maximum extent practicable and before the packaging is either refilled or cleaned of hazardous material and purged to remove any hazardous vapors.

Summary of requirements

Shipping papers. The shipping papers must:

• Indicate the fact that a material is an elevated temperature in the proper shipping name, or have the word “Hot” immediately preceding the shipping name (172.203(n)).
• Have an appropriate notation such as “Maximum operating speed 15 mph” for elevated temperature materials transported by rail under the exception in 173.247(h)(3).

Markings 172.325. Bulk packaging containing elevated temperature materials must:

• Be marked on two opposing sides with the word “Hot.”
• Be marked “Molten Aluminum” or “Molten Sulfur” instead of the word “Hot” if the package contains molten aluminum or molten sulfur.
• Be marked with letters that are at least:
  • 100 mm (3.9 inches) for rail cars;
  • 25 mm (1.0 inch) for portable tanks with capacities of less than 3,785 L (1,000 gal); and
  • 50 mm (2.0 inches) for cargo tanks and other bulk packagings.
• Be marked with “Hot” on the package itself or in black lettering on a white square-on-point configuration that is the same size as a placard. The word “Hot” may be displayed in the upper corner of a white square-on-point configuration that also displays the required identification number. The word “Hot” must be at least 50 mm (2 inches) high.
• Be marked, in characters at least 4.8 mm (3/16 inch), with the manufacturer’s name, date of manufacture, design temperature range, and maximum product weight (load limit for tank cars) or volumetric capacity. This marking must be durable and in a location readily accessible for inspection (173.247(g)).

Placards 172.504. Bulk packages containing elevated temperature materials may require placards, such as Class 3 or Class 9. The Class 9 placard is not required for domestic transport.

Residue 173.29(g). A package that contains a residue of an elevated temperature material may remain marked as when it contained a greater quantity, even though it no longer meets the definition of an elevated temperature material.

Exceptions. For a bulk packaging containing solid elevated temperature materials, the regulations require only that the word “Hot” be on two opposing sides of the packaging (173.247(h)(4)).

Bulk packaging used to transport molten metals and molten glass by rail are excepted from the packaging requirements in 173.247, if restricted to operating speeds less than 15 mph and a notation indicating this is on the shipping papers (173.247(h)).