The units are modular.
Ramp metering allows more vehicles to use the freeway.
Speeds also increase an average of 35 percent, while the accident rate decreases 40 percent with metering. Overall, this helps reduce fuel consumption, lessens air pollution and makes roadway travel more safe and efficient. Ramp metering controls the flow of traffic onto the freeway and reduces congestion in two ways. As traffic increases, the space between cars lessens and merging becomes increasingly difficult. When more than one car at a time enters the freeway, people have to jockey for position resulting in more congestion.