TRAFFIC CONTROL

This module discusses the principles of

traffic control which involves traffic control
devices and aids used in controlling of traffic
flows. It is imperative for the learner
particularly the future traffic enforcers to
have a vast knowledge on how traffic is
being controlled.
FUNDAMENTALS
OF TRAFFIC
CONTROL
TRAFFIC CONTROL
Ø refers to procedures, devices, and communication
systems that help vehicles and vessels safely share
the same roads, rails, waterways, or air space.
Ø establishes a set of rules and instructions that drivers,
pilots, train engineers, and ship captains rely on to
avoid collisions and other hazards. Safe travel for
pedestrians is an additional goal in highway traffic
control.
A. As Applied to Land Transportation
Øa system of traffic engineering, employing
prescribed traffic rules and regulations
and devices such as signals, and markings,
to relieve vehicular congestion and air
pollution, and to promote safety and
pedestrian mobility, usually in heavily
populated urban areas.
B. Control Techniques
Following are the comprehensive systems used:
1. access-road meters to monitor and control
motorway;
2. closed-circuit television surveillance to detect
quickly any deterioration in traffic flow; and
3. emergency services to provide aid in case of
accident and injury.
C. Other traffic-control techniques include:
1. the use of one-way streets,
2. enforcement of traffic flow regulations,
3. channelization (building traffic islands,
turning lanes and so on), and
4. the use of traffic signals.
D. Highway Traffic control
Ø Motorist depend on traffic control
devices to avoid collisions and travel
safely to their destinations.
1. Traffic Signs
Ø are the most extensively used form of traffic
control in the United States. More than 55 million
traffic signs in the nation’s roadside. They provide
i n fo r m a t i o n a b o u t s p e e d l i m i t s a n d ro a d
conditions. They direct traffic along certain routes
and to specific destinations. By using signs, traffic
control planners tell drivers what to do, what to
watch for, and where to drive.
2. Pavement Markings
Ø Pavement markings separate opposing streams of traffic
and direct vehicles into proper positions on the roadway.

For example:
Ø pavement markings delineate turn lanes at intersection and
establish no-passing zones. White and yellow paint is
customarily used for pavement markings. Reflective devices
are more visible at night and are used in some locations to
mark lanes and other significant places on the road.
3. Traffic-Signal
Ø are installed to permit safe movement of vehicles and
pedestrians at busy intersections.
Ø the light signal is probably the most easily recognized traffic
control device. At a busy intersection in a large city, a traffic
signal may control the movements of more than 100,000
vehicles per day. Traffic signals direct streams of vehicles and
pedestrians when to go, stop, or proceed with caution. The
signals increase the traffic handling capacity of most
intersections. They can work independently on timers, or
connect to computer-controlled system that operates over
several intersections.
4. Priority Control
Ø one of the oldest method of traffic control, one
form of transportation is given priority by
restricting or banning other forms of
transportation.
In the 1st century BC, Roman Emperor Juluis Caesar
banned wheel traffic from Rome during daytime,
which allowed pedestrians and horse riders to move
freely around the city. Some modern cities ban or
restrict truck travel through certain neighborhoods.
5. Restraints
Ø As an alternative to banning traffic, traffic control
planners use devices to discourage heavy use of
route. Island built in the centers of intersections
force drivers to proceed slowly. Speed bumps
discourage high-speed commuting through
residential neighborhoods. Concrete median
strips prevent vehicles from making turns except
at intersections.
Bus-lanes and high occupancy vehicles (HOV)
lanes exist in many urban areas. Only specified
types of vehicles, primarily those carrying
several occupants’ vehicles, primarily those
carrying several occupants, can use these lanes.
By giving priority to high occupancy vehicles,
transportation planners encourage carpooling
and reduce congestions.
6. Restraints
Ø as an alternative to banning traffic, traffic control
planners use devices to discourage heavy use of a
route. Island built in the centers of intersection
force drivers to proceed slowly. Speed bumps
discourage high-speed commuting through
residential neighborhoods. Concrete median
strips prevent vehicles from making turns except
at intersection.
TRAFFIC SIGNS
Traffic Signs
Ø are used to convey quickly and accurately the wide
range of information needed by road users, particularly
vehicle drivers, and to promote a safe and efficient use
of the road system like traffic signal lights and road
markings.
Ø refer to any device mounted on portable support
whereby a message is conveyed by means of words or
symbols officially installed for the purpose of regulating,
warning, or guiding traffic.
Traffic signs are installed to serve
the following functions:
1) to control traffic,
2) to safeguard the flow of traffic,
3) to expedite traffic, and
4) to guide traffic and motorists.
Standardization of traffic signs
Ø shall conform to the standards set forth in the erection
and display of standard road signs and markers as
prescribed by the DPWH as to shape, color, dimension,
shape, size, height, letterings or symbols.

Traffic signs
Ø shall be installed only under public authority or by the
official having jurisdiction for that purpose, and it shall
not bear any commercial advertisement.
A. Historical Background
In Britain
Ø early sign post was erected by private individuals at their own expense.

In 1648
Ø parishes were required by law to place guidepost at crossroads

In 1733
Ø these and mileposts were required to be erected and maintained by
Turnpike Trusts.

The Motor Car Act of 1903

Ø made local authorities responsible for placing certain warning and
prohibitory signs.
With increased international travel after World War II, discussions took
place in the United Nations (UN) on the introduction of international
traffic signs.

However, it was not until 1965 that United Kingdom (UK) signs were
changed to conform to the European system.

In 1995, it was estimated that there were 2, 500,000 signs and signals,
850, 000 road markings and 7,000,000 road studs on the roads in England
alone.

On the other hand, the United States (US) adopted the signs in the 1970s
and developed a set of national standards for sign, color, shape, and
usage.
On June 6, 1973
Ø the Philippines through P.D. 207 declared as part of the
laws of the Philippines the UN Vienna Convention on
road traffic, signs, markings and signals.
Ø the participating countries of this convention have
agreed to accept the system of traffic, road signs,
signals and symbols and road markings described in
said convention and to adopt the same to facilitate
international road traffic and to increase road safety.
B. International Traffic Signs
Ø as explained in the Vienna convention, the
sy ste m o f s i g n s a n d s i g n a l s w h i c h i t h a s
prescribed is based on the use of shapes and
colors, characteristics of each class of sign, and
whenever possible on the use of graphic symbols
rather than inscriptions with few exceptions one
of which is the STOP sign of the United States.
Basic sign shapes:
1. Round and red sign
Ø regulates the movement of turning and passing traffic
regulations
2. Round black yellow signs
Ø a warning that you are approaching a railroad crossing
3. Equilateral triangle red signs
Ø a sign at the intersection directing drivers to yield the
right-of-way to vehicles in the road being crossed
4. Eight-sided (octagonal) red and white stop sign
Øthe most popular and understood sign by all
tongues and colors
5. Triangle red and black sign
Øapproaching a danger zone, hill, slope, winding
road, and other
 C. Classification of International
Traffic Signs
1. Danger Warning Signs
Ø these signs are also known as “caution signs.”
Ø these signs have an equilateral triangular shape
with one side horizontal and having red borders.
These are signs intended to:
a. warn motorist of approaching
hazardous road conditions,
b. seek caution for the approaching
road hazards, and
c. call the reduction of speed.
2. Regulatory Signs
Ø these are signs which impose legal restrictions
applicable at particular location usually
enforceable in the absence of such signs.
Ø are usually round in shape with the exception of
“Stop Signs” and “Yield Signs”.

These signs are further classified into two:

a. prohibitive and restrictive signs, and
b. mandatory signs.
These are intended to:
a. inform road users of certain laws and
regulations, and
b. special obligations, instructions, or
prohibitions which they must comply with
and violations of which constitute
misdemeanor.
3. Informative Signs
Ø these signs are also known as “guide signs”,
or “direction signs.”
Ø the rectangular shape white-colored on
blue background is used for informative
signs.
Ø green background is usually used for route
markers and destination signs.
Informative signs are intended to:
a. guide motorists along established routes,
b. inform the motorists of the proper roads,
and
c. help motorists along the way in the
simplest and direct method.
CLASSIFICATION OF TRAFFIC SIGNS IN
THE PHILIPPINES
Road signs in the Philippines
Ø are regulated and standardized by the Department of Public
Works and Highways.
Ø most of the signs reflects minor influences from American and
Australian signage, but keeps close to the Vienna Convention as
an original signatory.
I. REGULATORY SIGNS
ØRegulatory signs indicate the application of legal
or statutory requirements.
Øthese signs require driver's compliance.

For example:
Øobligation to give way at intersections, control of
parking of vehicles, and speed limits.
TYPES OF REGULATORY SIGNS
A. PRIORITY SIGNS
B. DIRECTION SIGNS
C. RESTRICTIVE SIGNS
C. RESTRICTIVE SIGNS
C. RESTRICTIVE SIGNS
D. SPEED SIGNS
E. MISCELLANEOUS SIGNS
II. WARNING SIGNS
ØWarning signs are used to warn
motorists of potentially hazardous
conditions on or adjacent to the
road.
TYPES OF WARNING SIGNS
A. Horizontal Alignment Sign
B. Intersection and Junction Sign
B. Intersection and Junction Sign
C. Road Obstacle Signs
C. Road Obstacle Signs
III. GUIDE OR INFORMATION
SIGNS
ØGuide or information signs inform
road users about the direction and
distances on the route they are
following.
TYPES OF GUIDE OR INFORMATION SIGNS
A. Advance Direction Signs
B. Intersection Direction Sign
C. Reassurance direction signs
TRAFFIC SIGNAL
LIGHTS
A. Rationale
Ø Regulating traffic flow at intersections and road
crossings is just a matter of alternating the GO
and STOP signal so that every driver gets his
"fair share".
Ø As a result of this, traffic lights were invented
to relieved the traffic policeman of the
mechanical duties of alternating traffic to make
everybody happy.
B. Problems Concerning Traffic Lights
1. A society that has little or no respect for traffic laws will have a hard
time respecting the advantages that a traffic light can offer specially when
there are no traffic enforcers around. Sadly, to say, Filipino society is one
o f t h o s e i n w h i c h re s p e c t fo r t ra f f i c l aws n e e d s t re m e n d o u s
improvements.
2. When a traffic light suddenly becomes inoperative, very seldom does
order and a sense of discipline prevail. It always ends up as a massive
free for all.
3. Not only drivers are guilty of disobeying traffic lights but PEDESTRIANS
have a habit of turning DON'T WALK signs into WALK signs effectively
STOPPING traffic that should really be GOING.
4. Even if there are traffic enforcing officers present, they very seldom do
anything about pedestrians swarming around in droves, holding up traffic.
C. Classifications of Traffic Signal Lights
1. Traffic Control Signals
Ø these are signal lights designed primarily to
control and regulate traffic flows.
Ø are devices placed along, beside, or above a
roadway to guide, warn, and regulate the flow
of traffic, which includes motor vehicles,
motorcycles, bicycles, pedestrians, and other
road users.
2. Special Pedestrian Signals
Ø help pedestrians cross at intersections with traffic
lights. The signal for pedestrians to walk is a white
walking symbol.
Ø pedestrians who have already begun to cross when
the hand signal appears, should go as quickly as
possible to a safe area. While they are crossing,
pedestrians still have the right-of-way over vehicles.
Ø these signal lights provide regulation for
pedestrians like the “WALK” and “DO NOT WALK”
signal lights.
3. Train Approach and Gates Signals
Ø these are usually installed on road-rail
intersections designed to inform
motorists of any approaching train on the
intersection.
4. Other Special Traffic Signals
Ø these are installed on traffic ways where
special regulations are emphasized like
“YIELD TO VEHICLES COMING FROM THE
LEFT”, and other similar regulations.
Traffic Signal Systems
1. The Fixed-time System
Ø a traffic control signal by which traffic is alternately commanded to
stop and permitted to proceed in accordance with predetermined time
schedule.
2. Progressive System
Ø these are signals at successive intersections along the artery are timed
to change from red to green at staggered intervals, permitting a vehicle
that maintains a constant speed to proceed without interruption under
normal circumstances.
3. Computerized Control of Signal Networks
Ø signal changes are not predetermined, but are ordered by the
demands of traffic and are directed by computers that operate on the
basis of traffic information relayed from vehicle sensors on the streets.
D. Specific Meaning of Traffic Lights
1. Steady Red
a) STOP at the designated line.
b) Vehicles will be crossing from the "other side".
c) Expect pedestrians to cross at the pedestrian
lane.
d) Unless specified, you can TURN RIGHT after a
FULL STOP to clear traffic coming from the left.
2. Steady Green
a) It is the turn of the vehicles on the other side to
STOP.
b ) Pe d e st r i a n s a re n o t a l l o we d to c ro s s t h e
pedestrian lane in front of you.
c) Unless specified, you can move up to the middle
section of the intersection and make a left turn when
clear.
d) Vehicles GOING STRAIGHT have the right of way.
e) DO NOT ANTICIPATE A GREEN LIGHT.
3. Steady Green Arrow
a) GO
b) Vehicles turning left can do so.
c) On coming straight traffic is still RED
to give way for the vehicles turning left.
d) DO NOT ANTICIPATE A GREEN ARROW.
4. Steady Yellow
a) PREPARE TO STOP
b) It is the turn of the vehicles on the
other side and will be given the GO
signal shortly.
c) DO NOT BEAT A YELLOW LIGHT.
5. Flashing Red
a) This is the same as a STOP SIGN.
b) STOP at the designated line.
c) Vehicles will be crossing from the "other
side".
d) Expect pedestrians to cross at the
pedestrians’ lane.
e) PROCEED WHEN CLEAR.
6. Flashing yellow
a) This is the same as a YIELD SIGN.
b)Proceed through the intersection with
CAUTION.
c) You have the right of way over a flashing
RED LIGHT.
d) Vehicles on the other side will proceed
after coming to a FULL STOP.
7. Steady Green and Steady Left/Right
Arrow
a) Vehicles can go straight or vehicles on the left
lane can make a left turn.
b) Vehicles can go straight or vehicles on the right
lane can make a right turn.
c) The RIGHT GREEN signal might or might NOT
have a road sign disallowing a right turn while
the RED light is ON.
TRAFFIC SIGNAL BLACKOUT
Ø If all traffic signal lights are not working
because of an electrical power failure, you
must stop at the intersection and then
proceed when you know other turning and
approaching vehicles, bicycles, or pedestrians
have stopped. A blacked-out traffic signal
works the same as a four-way stop
intersection.