2024 DOT Hazardous Materials Regulations

April 29, 2024


What is considered a hazardous material?

Hazardous materials are substances or materials that the U.S. Department of Transportation (DOT) has determined to be capable of posing an unreasonable risk to health, safety, and property when transported in commerce. These materials require careful handling and specific regulations to ensure safe transport. 

9 categories of hazardous materials:

  1. Explosives: Materials that are capable of causing an explosion or a detonation. This category includes different classes of explosives ranging from those used for industrial purposes to fireworks.
  2. Gases: This encompasses compressed, liquefied, or dissolved under pressure gases. Examples include propane, oxygen, nitrogen, and helium.
  3. Flammable Liquid and Combustible Liquid: These are liquids prone to ignition under certain conditions. They include commonly transported fuels like gasoline and other substances that can ignite easily.
  4. Flammable Solid, Spontaneously Combustible, and Dangerous When Wet: Materials in this category are solids that pose fire risks, either through spontaneous combustion or when they come into contact with water.
  5. Oxidizer and Organic Peroxide: These substances can either intensify a fire or react dangerously without an ignition source. Handling these requires particular caution due to their reactive nature.
  6. Poison (Toxic) and Poison Inhalation Hazard: This category comprises materials that are harmful or potentially lethal upon ingestion, inhalation, or skin contact. Utmost care is essential when dealing with these substances.
  7. Radioactive: These materials emit radiation and are used in various medical, industrial, and research applications. Stringent regulations govern their transportation due to their potential health risks.
  8. Corrosive: Corrosive materials can damage or destroy other substances they come into contact with, including living tissue and metals. 
  9. Miscellaneous: This category includes materials that don’t fit into the other categories but are hazardous enough to require specific handling precautions. This includes substances like dry ice, asbestos, and environmentally hazardous substances.

Limited Quantity Requirements

The ORM-D classification, also known as “Other Regulated Material-Domestic,” has been phased out from the DOT Hazardous Materials Regulations for all transportation modes. This change, which took effect on January 1, 2021, means that materials previously classified under the ORM-D category are now required to be shipped as “limited quantities”.


  • Shipping papers are not required for “limited quantity” ground or rail shipments.
  • Shipping papers will continue to not be required for ground or rail shipments of limited quantities, provided the packages are marked with the new limited quantity or “LQ” marking; unless they are also a hazardous substance, a hazardous waste, or a marine pollutant.
  • Shipping papers will be required for air and vessel shipments and a “limited quantity” or “LTD QTY” notation is still required on documentation for ocean shipments, but the “limited quantity” or “LTD QTY” notation is no longer required for air shipments except when the Y-Packing instruction is used.

In order for Carlile Transportation Systems to comply with the DOT Hazardous Materials regulations surrounding the various modes of transportation, we will require hazmat shipping papers and Safety Data Sheets “SDS’ for all materials meeting the “Limited Quantity” marking requirements effective as of December 31, 2020.

Hazmat shipping papers will need to be prepared in accordance with 49 CFR 172.200(b)(3) and must be offered at the time of tendering to Carlile. If you are not familiar with preparing shipping papers on items, you are shipping “limited quantity”. You can specifically express or indicate on the freight bill “ground movement only”.

DOT hazardous materials regulations marking requirements

A package containing a limited quantity of hazardous material is not required to be marked with the proper shipping name and identification (ID) number when marked in accordance with the white square-on-point limited quantity marking as follows:


  • For transportation by highway, water, and rail: The top and bottom portions of the square-on-point and the border forming the square-on-point must be black and the center white.
  • For transportation by water: The new marking with minimum dimensions of 250 mm on each side is required on cargo transport units containing limited quantities and no other DOT hazardous materials on one side or end of the exterior of the unit
  • For Transportation by air: The top and bottom portions of the square-on-point and the border forming the square-on-point must be black and the center white and the symbol “Y” must be black and located in the center of the square-on-point and be clearly visible. Limited quantity shipments by air must display hazard labels, be marked with the proper shipping name and identification number in addition to the new limited quantity marking. Packages shipped by air are no longer required to be marked with the words “Limited Quantity” or “Ltd Qty”.
  • Ground and water shipments – “Limited Quantity”.  Shipping papers – Ground not required***Water required


Effective January 1, 2021, an “ORM-D” properly prepared and marked as an ORM-D is now “Limited quantity” is now to be required to be marked with the square-on-point limited quantity marking.

After December 31, 2020, we will no longer accept packages that are not in compliance with the DOT Hazardous Materials Regulations.

Please visit the Pipeline Hazardous Material Safety Administration (PHMSA) site for further details: http://www.phmsa.dot.gov/hazmat/regs

We have 9 terminal locations for shipping including Alaska, Minnesota, Washington, and Texas. Whether you are shipping hazardous materials from Houston to Fairbanks Carlile’s Alaskan shipping services can help your package arrive safely at its destination.

 If you have additional questions, or concerns or need assistance with DOT Hazardous Materials Regulations, or Alaskan Trucking & Logistics Services please contact Customer Service:

Customer Service:


Thank you for choosing Carlile Transportation as your shipping and logistics solution provider.