What are those horizontal lines you see on the road for?

It’s more likely that you’ve already seen (or experienced) multiple horizontal lines that look like parallel pedestrian lanes on the highway. They make a pretty annoying sound and vibration when you pass through them, right?

They are called rumble strips. Believe it or not, they’re not meant to give you a speed boost, nor to engage you to a time travel of some sort. These lines are a road safety feature that was first used back in 1952.

There are 4 types of rumble strips: continuous shoulder, centerline, continuous lane, and the most common here in the Philippines, the transverse. Basically, the first 3 are designed to warn you that you’re not in the correct lane anymore.

Transverse rumble strips (TRS), on the other hand, tell you that you need to slow down because of an upcoming intersection, stopping point, construction zone, or toll plaza. You usually see them on expressways and multiple lane avenues where cars are faster. In our country, TRSs are also placed in the middle of long, boring highways—like the Tarlac-Pangasinan-La Union Expressway (TPLEX)—to keep you awake.

Its effectivity has been proven over time. In fact, U.S. Federal Highway Administration Research and Technology conducted a research and concluded that TRSs can be effective in reducing severe injury crashes.

Next time someone asks you what those lines are, you know what to answer them.