STOP SIGNS
Stop signs are used where traffic is required to stop, except where an intersection
is signalized. Due to the substantial inconvenience to motorists, stop signs are used only where warranted
or required by law. This means that the installation must be justified by the specific circumstances and unique
features of a particular intersection. The following technical criteria are found in the Caltrans Traffic Manual
and usually provide for the smaller or lower volume street to stop for the larger and higher traffic volume
(busier) street.
The following conditions may warrant the installation of a stop sign:
- On a less-traveled road at its intersection with a main road.
- On a rural road or city street at its intersection with a state highway.
- At the intersection of two main highways. The highway traffic to be stopped depends on approach speeds,
volumes and turning movements. For a two-way stop, the signs are posted on the minor street to stop the lesser
flow of traffic.
- On a street entering a legally established "through" highway or street.
- On a minor street where the safe approach speed to the intersection is less than 10 miles per hour.
- At other intersections where a combination of high speed, restricted view and accident records indicates
a need for right-of-way control.
- At a blind intersection. A blind intersection is a location where the driver has less than one hundred
(100) feet of sight distance for approaching cross traffic. Stop signs are generally posted for the less-traveled
street, but, there may be cases where studies justify the posting of a stop sign for a major street, as with
a multi-way (4-way) stop. Safety considerations may also justify the stopping of the greater flow of traffic
to permit left-turning traffic to proceed safely.
The multi-way stop (otherwise known as a 3-way or a 4-way stop) can prove useful
at some locations. It is ordinarily used at intersections where the volume of traffic is approximately equal.
In evaluating the need for a multi-way stop, Fontana Traffic Engineers compare the existing conditions with
the minimum guidelines or "warrants."
The following warrants or guidelines are used to consider the installation of a multi-way stop installation.
Warrant 1 - Traffic Signal is Warranted
For intersections where traffic signals are needed and warranted, the multi-way stop sign can be installed
as an interim (or temporary) measure to control the traffic flows while arrangements are being made for the
financing and construction of the traffic signals.
Warrant 2 - Traffic Collision Problems
An intersection would be considered a problem if there were three or more reported collisions within a twelve
(12) month period that were susceptible to correction by the installation of a multi-way stop. The type of
collisions susceptible to correction by the installation of a multi-way stop are left-turn and right-turn collisions
as well as right angle collisions.
Warrant 3 - Minimum Traffic Volumes
For an intersection to meet this warrant, the total number of vehicles entering an intersection from all directions
must average at least 500 vehicles per hour for any 8 hours of an average day. The intersection must also have
a combined vehicle and pedestrian volume on the minor street or highway of at least 200 units (the combination
of vehicles and pedestrians) per hour for the same 8 hours, with an average delay of at least 30 seconds per
vehicle on the minor street during the maximum (peak) hour. The above guidelines are applicable where the approach
speed on the major street is less than 40 mile per hour. When the 85th percentile approach speed
of the major exceeds 40 miles per hour, the minimum vehicle volume warrant is 70 percent of the above requirements.
The 85th percentile speed is the speed at which 85 percent of all vehicles do not exceed during
off peak traffic conditions.
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