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Traffic Signals Brochure

What Harm Can A Signal Cause?

Causing traffic delay and congestion.
Obviously, a traffic signal will cause traffic on the major road to stop at times when it previously did not have to stop. This often contributes to traffic congestion. In some situations, a signal also may force vehicles on the side street to wait to cross the major road even when gaps in the traffic stream would have allowed them to cross sooner.

Balancing safety.
Experience has shown that, while reducing angle crashes, the installation of a traffic signal typically will increase the frequency of rear-end collisions that occur at an intersection. The trade-off of additional rear-end collisions for fewer, but normally more severe, angle crashes is acceptable where numerous angle crashes have occurred. However, where there is no history of angle crashes to offset the likely increase in rear-end collisions, the overall safety of the intersection likely will deteriorate if a signal is installed.

Additional consequences.
Where a signal is not justified, the unnecessary delay frustrates drivers. They become more apt to disobey the signal and to increase their speeds to avoid stopping or to make up for lost time after stopping. Noise from traffic stopping and starting at a signal can be irritating in both residential and commercial areas. An inappropriate signal also can cause some drivers to use alternate routes, thereby increasing traffic on lower volume residential streets. Additionally, a signal located too near another signal on a two-way road prevents a beneficial signal progression.

How Does One Request a Traffic Signal?

Keeping fingers on the traffic pulse.
Traffic engineers and others responsible for the safe and efficient movement of traffic are continually monitoring traffic movement and usually are among the first to spot an intersection problem before it becomes a major one. Public input is also quite valuable.

Seeking the correct solution.
Keep an open mind. Simply describe the situation or problem rather than request or demand that a signal be installed. In many instances, other solutions will yield more favorable results. Sometimes, no change is needed.

Who to call for help.
The SHA and the larger local jurisdictions have traffic engineering units that routinely address these matters. If the intersection is outside Baltimore City and involves a MD, Interstate, or US numbered route, contact the SHA District Office listed in this pamphlet for the County where the intersection is located. Otherwise, contact the local traffic engineering agency or, if none, the roads, street, public works or law enforcement agency responsible for traffic operations in the city or county where the intersection is situated.

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