A typical passenger vehicle driver may not think twice about low bridges, but for semi-truck drivers, these are serious potential hazards. Low-clearance accidents are collisions where a truck, bus, recreational vehicle (RV), or other large vehicle makes contact with the top of a bridge, power lines, or other structure that does not provide enough vertical space for the vehicle to pass through. These accidents often cause expensive damage to both the vehicle and the infrastructure, and it’s important to be aware of low-clearance obstacles.
Why Are Some Bridges Low-Clearance?
Since 72.5% of the nation’s freight travels by semi-truck, it’s essential for transportation infrastructure to accommodate these vehicles. On major interstate highways, overpasses have to meet minimum requirements for height to allow large vehicles to pass underneath them easily.
However, in less-populated areas or those with older infrastructure that was designed before semi-trucks became widespread, bridges may be too low for trucks or other tall vehicles to go under. These areas must be clearly marked with a sign so truckers can avoid them and find an alternate route.
Damage Caused by Low Bridges
If you’ve ever seen the aftermath of a low-clearance accident, it’s clear how significant the damage can be. Repair costs for the truck are significant, as are the costs of damaged cargo. Additionally, repair costs for the infrastructure that the truck collided with can easily reach six figures.
Beyond damage to property, low-clearance accidents can also result in injuries, especially if there is any flying debris.
How to Avoid Low-Clearance Accidents
Here are some tips for truckers to avoid collisions with low bridges:
1. Pay Attention to Road Signs
All low bridges or other obstacles must be marked with a low-clearance sign. This will list the height of the bridge so you can plan accordingly and find a way around the obstacle.
In general, you should pay attention to each and every sign you pass while you’re operating a semi-truck. Many driver trainers will even test you on this when you’re a rookie so you get in the habit of doing so. These signs have important information that could help you avoid an accident.
2. Use a Trucker-Specific GPS and Atlas
If you use a standard road atlas or GPS, it may not list low bridges, roads that have weight restrictions or otherwise don’t allow commercial vehicles, and other essential information to be aware of. Be sure you are using a GPS and atlas that are written for commercial drivers. That being said, don’t rely exclusively on these tools since road signs may tell you information the GPS or atlas doesn’t, especially if your route changes.
3. Trip Plan
Trip planning is a valuable skill for truckers. It helps you stay in compliance with hours of service (HOS) regulations, find parking more easily, and plan your route to avoid known hazards like low bridges. This doesn’t mean you’ll never encounter an unexpected low-clearance obstacle, but it does help you minimize the risk of being caught by surprise.
Become a Trucker with HDS
At HDS Truck Driving Institute, we teach our students how to become safe truckers. You can earn your commercial driver’s license (CDL) in as little as four weeks with our accelerated program.