Transportation

Does My Shipment Qualify for PHMSA’s Small Quantity Exception?

When are you subject to the U.S. Department of Transportation (DOT) hazardous materials requirements? Some of the more onerous regulations environmental, health, and safety (EHS) managers face are the tangled and confusing Hazardous Materials Regulations (HMR) under DOT’s Pipeline and Hazardous Materials Administration (PHMSA). Yesterday we reviewed PHMSA’s responses to three scenarios concerning hazmat transportation training. Today we will take a look at how PHMSA views the HMR’s small quantity exception.

Background on the small quantity exception

If you are shipping small quantities (typically 1 ounce or less) of certain hazardous materials domestically by highway or rail, the shipment is exempt from HMR requirements if it meets the requirements of DOT’s small quantity exception. In order to use it, your materials must be covered by the exception, which are listed in 49 CFR 173.4, and you must meet the detailed packaging requirements of 49 CFR 173.4 that include:

  • Inner receptacle:
    • Contains hazardous material in quantities of between 1 gram (g) and 30 g (or 30 milliliter (ml)) (as specified in the regulation)
    • Is constructed of at least 0.2 millimeter (mm) (0.008 inch) thick plastic (or earthenware, glass, or metal)
    • Is not liquid-full at 55°C (13°F)
    • If with a removable closure, has closure held securely in place
    • Is secured in strong outer packaging


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  • Absorbent and/or cushioning meet specific requirements
  • Prototype packaging that must pass a drop test and compressive load test
  • Completed package that:
    • Does not contain materials forbidden from being transported under 49 CFR 173.21
    • Does not exceed 29 kilogram (kg) (64 pounds)
    • Is not opened or altered until no longer in commerce
    • Is marked with the statement, “This package conforms to 49 CFR 173.4 for domestic highway or rail transport only.”


Current hazardous materials regulations (HMR) have been amended to align better with international standards, which have seen several recent changes. Click here to learn more!


PHMSA’s views in a couple of scenarios

Note. It bears repeating that the small quantity exception is available for only domestic highway and rail transportation.

In one interpretation letter, PHMSA addresses a query as to whether a shipment that has been marked and labeled for air transportation may be transported without placarding the transport vehicle during the domestic ground segment of transport. The answer is “yes.” According to PHMSA, such shipments are not subject to the requirements for shipping papers, markings, labels, or placards when transported by highway or rail, including when the transportation is performed before or after transportation by aircraft.

Another PHMSA interpretation letter harkens back to yesterday’s Advisor concerning hazmat training. A transportation company wanted to know if employees handling a product that meets the small quantity requirements needed hazmat transportation training. The answer is “no.” According to PHMSA, materials that meet the small quantity exception requirements are not subject to any other HMR requirements. Therefore, employees who handle small quantity shipments are not subject to hazmat transportation training requirements unless they perform other hazardous materials transportation functions.