Potential dangers during inspections of compressed or liquid natural gas or hydrogen bulk packages contained within a truck trailer or cargo tank have sparked warnings from several commercial vehicle safety organizations. The Federal Motor Carrier Safety Administration (FMCSA), the Pipeline and Hazardous Materials Safety Administration (PHMSA), and the Commercial Vehicle Safety Alliance (CVSA) all issued safety alerts to commercial vehicle inspectors who encounter these highly combustible materials.

If inspecting trailers containing these forms of natural gas and hydrogen create dangers for inspectors, then motor carriers and drivers hauling them must also take caution.

CVSA and the federal agencies identify these dangers:

  • Hydrogen and natural gas are odorless and highly flammable.
  • Any leak within the cargo tank or from a high-pressure cylinder enclosed in a truck trailer or freight container means these lighter-than-air gases will expand to create a volatile environment.
  • Any spark – from static, electricity, flames or even electronic devices – can set off the built-up gases. Just opening a trailer or compartment door may generate friction, igniting the gas.

Of course, truck drivers must at some point open trailer doors and cargo tank compartments, whether for inspections or loading and unloading the cargo being transported. When the cargo is compressed or liquid natural gas or hydrogen, truck drivers should take these cautionary steps:

  • Shut off the truck’s engine.
  • Leave any cell phone or other electronic device in the cab.
  • If a personal air monitor is available, check for flammable conditions around the trailer.
  • Look at the vent atop the cargo tank or trailer for any signs of fumes or gas vapors. Remember: hydrogen burns almost invisibly.
  • Listen for any hissing sound; it may be a leak.
  • Do not proceed if the personal air monitor, visual or auditory cues indicate a leak. Instead, leave the immediate area and call for support from the motor carrier’s hazmat specialist.
  • If all appears okay, open the trailer or compartment doors, stepping to the side to allow the interior to air out for a minute.

Following these steps helps ensure the safe handling and transport of all hazmat, including hydrogen and natural gas:

  • Motor carriers handling any hazardous material must register with PHMSA.
  • Truck drivers operating a vehicle transporting hazardous materials must have a hazmat endorsement on their commercial driver’s license.
  • Motor carriers should coordinate closely with hazmat shippers on how that cargo should be loaded and braced. Important: the number one hazmat violation is “Package not secure in vehicle.” With hydrogen and natural gas, that violation may include a conflagration.
  • Motor carriers should ensure that all their personnel, including truck drivers and personnel involved in cargo loading, receive thorough training in the specific characteristics of the hazmat transported.
  • Get started by reading the PrePass whitepaper on Hazardous Materials Compliance.

Truck drivers, and commercial vehicle inspectors, need to be cautious when shipping papers and hazmat placards show hydrogen and natural gas are inside. But with preparation and training by motor carriers and drivers alike, the end result should be a safe, and clean, inspection.

The PrePass blog and podcasts are published as a public service of PrePass®, the most reliable and technologically advanced weigh station bypass and integrated electronic trucking toll payment platform in North America. PrePass also includes INFORM™ Safety and INFORM™ Tolling software for improving truck safety scores and lowering toll costs.