Driving 101: Speed limits decoded

Breaking down the methods behind how speed limits regulate our road travel

If you’ve been driving for quite some time in the Philippines, you’ll know firsthand that the driving conditions and norms are ambiguous at best, and usually “played by ear” at the worst. While road markings and signs have come a long way since many years ago, the lack of proper enforcement and understanding to begin with is the main cause behind driving errors and road accidents.

Today, we’re going to look at a specific kind or road sign: the speed limit. We’ll talk about their uses, understanding why they exist, and what you can expect when you see on of these regulatory limits on the road.

Related: Quick guide to speed limits in the Philippines

What is a speed limit?

Simply put, the speed limit denotes the maximum allowable speed that vehicles may travel on that specific section of roadway. Vehicles may not exceed the speed limit unless they are prepared for violations and corresponding penalties.

On specific roads, speed limits can also be vehicle specific, covering vehicles such as passenger cars, trucks, buses, and motorcycles. In the absence of specific vehicle speed limits, the posted limit on the side of the road applies to all types of vehicles.

Remember that speed limits are the maximum allowable speeds when traveling on the road in perfect conditions. Meaning, clear weather with good visibility, flowing traffic, and no obstructions or road debris. As traffic conditions change, vehicle speeds need to adjust to keep everything safe and prudent for all motorists.

Who creates or decides speed limits?

In the Philippines, speed limits are set under Republic Act No 4136 and the Land Transportation and Traffic Code. Legally, local government units (LGUs) and traffic management offices of private areas or subdivisions may also set their own speed limits in accordance to the types of roads that fall under their jurisdictions.

In the absence of a posted limit, the limits set by Republic Act No 4136 and the Land Transportation and Traffic Code take precedence.

What influences speed limits?

A number of factors influence the presence of speed limits and the allowed maximum speed. Done properly, studies are conducted on the road, identifying the type of traffic, how it flows, how vehicles interact with one another, and identifying points of conflict.

Intersections, blind corners, the presence of pedestrians, and the vicinity of establishments and buildings close to the road all influence the speed limit. Roads with fewer intersections — with fewer travelers moving perpendicular to one another — can generally sustain higher maximum speeds and still be considered safe. Roads with more intersections, and often more motorcycles/bikers and pedestrians, have more people moving at different speeds in different directions, and need lower maximum speeds.

Can speed limits change?

Yes, and they should. Regulating bodies and agencies that have control over a road must always be on top of any mishaps or changes in driver behavior. Have drivers been traveling much slower due to traffic, or in the presence of too many intersections or turns? Maybe the speed limit might need lowering for better flow. Are there too few vehicles using the lanes, and the lack of traffic buildup is throughout the day? Maybe a higher speed limit to facilitate faster travel could work.

How the area develops or how much more congested an area will be in a decade should all be taken into consideration as well, as it will require extra roads and much more complex traffic control schemes, like traffic lights, maybe roundabouts, and more pedestrian focused infrastructure.