You’ve likely felt the change in the air when a semitruck passes your vehicle. The air pressure shifts dramatically and it can pull or push your vehicle. It can be frightening and make it feel like the semi is much too close, even when it is in the proper lane.
You’re certainly not imagining how this happens. Here is a video showing what the semi does to a cloud of steam as it goes by. It’s something that most people have felt at some point, and it’s even more dramatic when you’re walking or riding a bike. If a semi passes a bicycle at high speeds, the force of the wind could be enough to knock the cyclist over or pull them into the traffic lanes.
How do you prevent this?
An 18-wheeler displaces so much air that it is usually going to cause this type of disturbance at high speeds. There’s no way to avoid that; it’s just physics. But you can prevent it from harming cyclists or others on the road.
For instance, semi drivers can reduce this effect simply by slowing down. They are also required by law to give at least three feet of clearance. If they don’t have the space to do so, then they are required to slow down and wait until they can safely pass. So, in theory, this should either mean that the semi is moving at a low speed or that it is far enough away that the air pressure can’t impact a cyclist.
Of course, if you ride often, you know that drivers do not always respect this three-foot rule. They often pass far too close to cyclists, perhaps because they’re unwilling to wait for a break in oncoming traffic. This unfortunately makes some drivers view cyclists negatively, even though the cyclists are doing nothing wrong. But it can build up animosity between the two groups that will cause motorists to drive more aggressively and get closer than ever.
Have you been injured?
If you do find yourself involved in an accident like this, you could suffer severe injuries. It’s very important to understand all the legal options you have to seek compensation.