Low-Clearance Obstacles

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By Northland Insurance
2 minutes

Trucks striking low bridges, power lines, or signs is not an unusual occurrence, especially in metropolitan areas where these hazards are abundant. These collisions can result in costly damage to your vehicle and cargo, as well as property. It can also cause delays and damaged customer relationships. Missing or inadequate markings on low-clearance obstacles often contribute to the problem.


However, striking a fixed object is almost always considered a preventable incident. Here are some precautions you can take to help avoid these collisions:

  1. Know the height of your vehicle. If you are not sure about the exact height, measure it.
  2. Plan your route carefully. If you are not familiar with the route, consult with your manager. Navigation devices can be a helpful, but keep in mind that not all programs are designed for large commercial vehicles. Many crashes have occurred as a result of drivers following directions from navigation devices designed for small passenger vehicles.
  3. Watch for signs warning of a low clearance hazard.
  4. Be aware of less obvious obstructions, such as power lines and tree limbs. They may be difficult to see, and they often hang lower when weighted with snow or ice.
  5. When approaching a low-clearance obstacle, do not continue unless you are certain there is enough clearance.
  • Activate your emergency flashers, slow down and approach with caution.
  • Watch for signs showing the height of the obstruction.
  • Look for clues that there may not be enough clearance for your vehicle, such as damage to the bridge or overhang where it has been struck by other vehicles.
  • Inspect the roadway to see if it has been resurfaced recently. Resurfacing can reduce clearance by several inches, but signs may not be immediately updated.
  • Be aware that a thick layer of snow or ice can also reduce clearance.
  • If necessary, get out of your vehicle to inspect for sufficient clearance before proceeding. Also inspect the roadway under the low clearance for bumps that may reduce clearance once you proceed. As you do so, be cautious of other vehicles.
  • For longer vehicles, make certain your vehicle will not “bridge” a dip in the road. This can cause your vehicle to gain height as you drive under the obstruction.

Low clearance collisions, like most collisions involving fixed objects, are usually considered preventable because drivers are expected to watch for hazards and make adjustments to avoid a crash, especially with fixed objects. Planning your trip carefully and being alert for low clearance obstacles can help reduce the risk of being involved in this type of accident. Above all, don’t take a chance if you encounter a low-clearance obstacle. Make sure you have enough clearance before you proceed.

DOC#: LCT119

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