Traffic Facts

Will “Children At Play” Signs Help Slow Traffic?

Unnecessary signs can confuse and irritate motorists. They often give a false sense of security and can promote disrespect for all signs. Perhaps the best example is the “CHILDREN AT PLAY” sign.

While it may seem that this sign would protect neighborhood youngsters, facts indicate otherwise. Although some communities have posted these signs in residential areas, not one shred of evidence exists to show these signs help reduce pedestrian accidents or lower speeds. Studies have shown that many signs, which warn of normal conditions in residential areas, fail to improve safety.

Signs, which encourage parents and children to believe they have added protection (which the signs do not provide), result in a great disservice and can do more harm than good.

Children should not be encouraged to play within the street. Federal Standards reject these signs because they are a direct and open suggestion that this behavior is acceptable. Since children live on nearly every residential block, there would have to be signs on each street. Blocks with no signs might imply that no children live there, so it is okay to speed.

Because of these serious concerns, Arizona law does not recognize “CHILDREN AT PLAY” signs. Specific warnings for schools and crosswalks are available for use where they clearly serve a purpose.

Will More Stop Signs Slow Traffic On Our Street?

STOP signs installed in wrong places usually create more problems than they solve. Many requests are received for STOP signs to interrupt traffic or to slow speeding vehicles. However, studies in Arizona, and across the country, show that there is a high number of intentional violations when STOP signs are installed as nuisances or speed breakers.

Studies show that speed was reduced in the immediate vicinity of nuisance STOP signs. However, speeds were higher between intersections than before the signs were installed. This is caused by motorists “making up for lost time.” So-called nuisance STOP signs also increase air pollution, waste fuel, and create more traffic noise. State Law ARS 28-771 requires that (without STOP or YIELD signs): When two vehicles enter an intersection from different streets at the same time, the driver on the left shall yield right-of-way to the driver on the right.

The only exception is at a “T” intersection where the driver on the through street has the right-of-way. Low volume streets within neighborhoods tend to operate best under the State Right-of-Way law. This requires drivers to approach an intersection cautiously, and to control their speed to a reasonable level. However, STOP signs on one street tend to increase speeds on the other street since these motorists feel they no longer have to drive cautiously through the intersection. Under the right conditions, STOP signs can play an important role in traffic safety. National standards have been established to determine when STOP signs should be installed.

These standards consider traffic speed, the volume of vehicles, sight distance, and frequency of “gaps in traffic” to allow safe vehicle entry or pedestrian crossing. For safety purposes, when STOP signs are used, they should stop traffic on the lower volume street. Four-way stops are only helpful (or useful) when traffic volumes are high and approximately equal on all four approaches.

Traffic volumes of at least 500 cars per hour, for a substantial portion of the day, may benefit from four-way STOP signs. Most drivers are reasonable and prudent. When confronted with unreasonable and unnecessary restrictions, motorists are more likely to violate them, and they usually develop a contempt for all traffic signs…often with tragic results.

Will A Traffic Signal Reduce Accidents At Our Intersection?

Traffic signals don’t always prevent accidents. In most cases, accidents and severe injuries increase after they are installed. When signals are installed, right angle collisions are generally reduced, but total accidents often increase – especially rear-end collisions. Additionally, pedestrians are often lulled into a false sense of security. Traffic engineers consider the following points when deciding if a traffic signal will help more than in will hurt:

• Does the number of vehicles on intersecting streets create congestion?
• Is traffic so heavy that drivers on the side street try to cross when it is unsafe?
• Is pedestrian traffic heavy? If so, is the street they are trying to cross a wide, high speed, and busy street?
• Does the number of school children crossing the street require special controls? If so, is a traffic signal the best solution?
• Will a traffic signal allow for a smooth flow of traffic and avoid gridlock with a nearby signal?
• Does an intersection’s accident history indicate a signal will reduce the possibility of a collision?

Traffic engineers compare existing conditions against standards established after many years of study throughout the country. Under these conditions, a new signal will generally operate effectively. If established standards have not been met, congestion and motorist violations occur which cause more accidents.

Traffic signals at collector and local street intersections improve access onto major streets, which can result in more neighborhood cut-through traffic.

NOTE: It is our experience that a properly placed signal can improve the flow of traffic and de-crease accidents. An unnecessary one can be the source of danger and annoyance to all that use the intersection, including pedestrians, bicyclists and motorists.

Will A Lower Speed Limit Help Reduce Speeds?

A common myth is that posting a lower speed limit will cause drivers to slow down and will reduce accidents. Facts indicate otherwise. Research conducted throughout the country, over several decades, has shown that drivers are influenced by the type of street and the prevailing traffic conditions and not the posted speed limit.

Arizona’s Basic Speed Law (ARS 28-701) requires that: A person must drive at a speed that is reasonable and prudent under the existing conditions. In every event, speed must be so controlled as to avoid colliding with any object, person, or vehicle on the highway. It is the duty of all persons to exercise reasonable care for the protection of others.

Under Arizona law, the maximum speed limit in Tucson is 55 miles per hour. Other maximum speed limits established by law include the 25mph limit in residential areas and business districts, and the 15mph limit in alleys.

Even though these speeds are not always posted, all motorists are required to know the basic 15mph, 25mph, and 55mph speed laws. Speed limits between 25mph and 55mph may be established on the basis of traffic engineering surveys. These surveys include roadway conditions, accident records, and the prevailing speed of prudent drivers.

If an unreasonably low speed limit is posted, most drivers will ignore the signs, while a few may try to stay within the posted speed limit. This causes conflicts between faster and slower drivers, resulting in more accidents.

Unrealistically, low speed limits also increase the number of violators, and create a bad image for the police and the community.

Speed limits approaching yellow school crosswalks are 15mph when the portable signs are placed on the street. These zones may only be established based on traffic engineering studies, and used only for children going to and from school, when school is in session. (ARS 28-797)