Back to Blog
Hazmat11 min read

Hazmat Transportation: DOT Compliance Essentials

October 10, 2025
Transportation Compliance

Department of Transportation Hazmat Regulations

The Department of Transportation (DOT) regulates the transportation of hazardous materials to protect the public and the environment. These regulations apply to anyone who offers hazmat for transportation or transports hazmat.

Who is Regulated?

DOT hazmat regulations apply to:

  • Shippers: who offer hazmat for transportation
  • Carriers: who transport hazmat
  • Packaging manufacturers: who create hazmat containers
  • Training providers: who certify hazmat employees
  • Hazmat Classification

    Hazmat is divided into nine hazard classes:

    Class 1: Explosives

  • Division 1.1: Mass explosion hazard
  • Division 1.2: Projection hazard
  • Division 1.3: Fire and minor blast hazard
  • Division 1.4: Minor explosion hazard
  • Division 1.5: Very insensitive explosives
  • Division 1.6: Extremely insensitive articles
  • Class 2: Gases

  • Division 2.1: Flammable gas
  • Division 2.2: Non-flammable, non-toxic gas
  • Division 2.3: Toxic gas
  • Class 3: Flammable Liquids

  • Flash point below 141°F (60°C)
  • Class 4: Flammable Solids

  • Division 4.1: Flammable solid
  • Division 4.2: Spontaneously combustible
  • Division 4.3: Dangerous when wet
  • Class 5: Oxidizers and Organic Peroxides

  • Division 5.1: Oxidizer
  • Division 5.2: Organic peroxide
  • Class 6: Toxic and Infectious Substances

  • Division 6.1: Toxic
  • Division 6.2: Infectious substance
  • Class 7: Radioactive Materials

    Class 8: Corrosives

    Class 9: Miscellaneous Dangerous Goods

    Proper Shipping Names and UN Numbers

    Every hazmat must be identified by its:

  • Proper Shipping Name: - from the Hazardous Materials Table (49 CFR 172.101)
  • UN/NA Number: - four-digit identifier
  • Hazard Class or Division
  • Packing Group: (I, II, or III based on danger level)
  • Example: UN1203, Gasoline, 3, PG II

    Packaging Requirements

    Hazmat must be packaged in containers that:

  • Are authorized for the specific material
  • Meet performance standards
  • Are properly marked with UN specification
  • Are in good condition without leaks
  • Packing Groups indicate hazard level:

  • Packing Group I: - Great danger (most stringent packaging)
  • Packing Group II: - Medium danger
  • Packing Group III: - Minor danger
  • Marking Requirements

    All hazmat packages must be marked with:

  • Proper shipping name
  • UN/NA number
  • Shipper's name and address
  • Consignee's name and address
  • Special handling marks when applicable
  • Additional marks may include:

  • "Overpack" if multiple packages in outer container
  • Orientation arrows for liquids
  • "Limited Quantity" square-on-point mark
  • Marine pollutant mark
  • Labeling Requirements

    Hazmat labels are diamond-shaped warnings indicating hazard class:

  • Size: Minimum 3.9 inches (100mm) on each side
  • Placed on same surface as markings
  • Multiple labels for multiple hazards
  • Primary hazard closest to proper shipping name
  • Placarding Requirements

    Vehicles transporting hazmat must display placards when:

  • Any amount of Table 1 materials (explosives, poison gas, etc.)
  • Over 1,001 lbs aggregate gross weight of Table 2 materials
  • Placards must be:

  • On all four sides of vehicle
  • At least 10.8 inches on each side
  • Clearly visible
  • Maintained in good condition
  • Shipping Papers

    Every hazmat shipment requires shipping papers containing:

  • Proper shipping name
  • Hazard class or division
  • UN/NA number
  • Packing group
  • Total quantity
  • Emergency response information
  • Shipper's certification
  • Accessibility requirements:

  • Driver: within reach while seat belt fastened
  • When away from vehicle: driver's door or driver's seat
  • Carrier must retain for 375 days
  • Emergency Response Information

    Must accompany every hazmat shipment:

  • Immediate health hazards
  • Fire or explosion risks
  • Immediate precautions
  • Initial response methods
  • Initial first aid
  • This can be on shipping papers, separate document, or Emergency Response Guidebook.

    Training Requirements

    All hazmat employees must receive training in:

  • General awareness: - recognizing hazmat
  • Function-specific: - their particular job duties
  • Safety: - emergency response information
  • Security awareness: - recognizing security threats
  • In-depth security: (if security plan required)
  • Training records must include:

  • Name of employee
  • Completion date of most recent training
  • Training materials used
  • Name and address of trainer
  • Certification that employee was tested
  • Recurrent training: Required every three years (or sooner if regulations change).

    Security Plans

    A security plan is required for:

  • Any quantity of highly hazardous materials
  • Large bulk quantities of certain materials
  • Plans must address:

  • Personnel security
  • Unauthorized access
  • En route security
  • Common Violations

    Frequently cited issues:

  • Missing or incorrect shipping papers
  • Inadequate employee training/records
  • Improper packaging or damaged containers
  • Missing or incorrect markings/labels
  • Failure to provide emergency response information
  • Missing or incorrect placards
  • Shipping undeclared hazmat
  • Penalties

    DOT can assess civil penalties up to:

  • $89,678 per violation (2024)
  • $209,249 for violations resulting in death, serious illness, or severe injury
  • Criminal penalties may apply for willful violations.

    Resources for Compliance

  • 49 CFR Parts 100-185 (complete regulations)
  • Emergency Response Guidebook (free from PHMSA)
  • PHMSA website and hotline
  • Industry associations and training providers
  • Critical Dynamics provides comprehensive hazmat transportation training and compliance audits. Contact us to ensure your hazmat shipping operations meet all DOT requirements.

    Need Help With Your Safety Program?

    Our team of certified safety professionals is ready to help you implement the strategies discussed in this article.