Traf. Mgmt. & Acci. Inves.

7/31/2019 Traf. Mgmt. & Acci. Inves.

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TRAFFIC MANAGEMENT & ACCIDENT INVESTIGATION

By:

PROF. OSCAR GATCHALIAN SORIANO, LC

BSCrim, MSBA, MACrim, PhDCrim

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History of Transportation

The history of transportation can be conveniently--if over-simply--divided into period during which

motive power was most characteristically furnished

by human and animal muscle, by such natural forces

as wind and gravity, and by fuel-operated machines.

1. Manpower

Stone Age mans transportation of firewood and

of animals killed in the hunt probably led to the

invention of the sled. From the sled early man mayhave got the idea for ski pieces of smooth board

resembling sled runners but worn on the feet of the

hunterand later of snowshoes. The first

watercraft, the man-powered raft and canoe,

probably evolved from the floating log.

The greatest advance in land transport after

the sled was the wheel, probably first invented in

the Tigris-Euphrates Valley sometime before 3500BC. The ancient Egyptians took little or no part

in the invention. The great blocks of stone that

went to make the pyramids were floated on barges

down the Nile River and then moved over land on

sleds running on rollers. Gangs of slaves dragged


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the blocks of stone by means of large ropes, while

other slaves at the rear of sled picked-up the

rollers over which the sled had passed and hurriedaround and place them at the front. To raise the

blocks of stone to their positions in the pyramids,

the Egyptian built ramps.

2. Animal Power

But while human muscle power was still in

widespread use for transport in ancient Egypt,

animal muscle power was being widely exploited in

the other river valley civilizations. The ox, theass, and the camel were tamed somewhere in the

Middle East by 3000 BC. In arctic snows the

reindeer, which can carry a load of about 130 lbs.

(60 kg.) without much effort, is still widely used.

In the higher altitudes of the Himalayas the yak, a

species of ox, is used as pack animal. In India

the beast of burden is often the elephant. In Peru

the llama is domesticated and used as pack animal.

The horse was tamed somewhere in its native

habitat on the steppes of Central Asia. The

invention of the bit and bridle before 3000 BC gave

steppe folk control of the horse for riding. The

stirrup was not invented until Roman times,

probably somewhere in Western Asia. The earliest

known stirrups have been found in South Russia in

tombs dating from between 100 BC and 400 AD.

Until the invention of horse collar, about 900AD, horses were harnessed like oxen. A yoke

passed over the withers, and a strap tightened on

the horses chest when it pulled, half strangling

the animal. The Romans, knowing little anatomy,

did not realize that a good harness for the ox was

a very poor harness for the horse. This fact

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explains why the horse was little used as a draft

animal until late in the middle ages, whereas the

ox almost universally used as draft animal from3000 BC. Where the horse was used for

transportation during the middle ages, it was

mainly as a pack carrier at its sides.

Another invention that played a great part in

the history of transportation was the horseshoe.

In its wild state the horse can gallop for long-

distance on soft grass of the Asiatic steppes. But

if it is driven on a hard, metal road its soft

hoofs soon become broken and it goes lame. An ironhorseshoe, mailed around the edge of the hard hoof,

stops the hoof from breaking away. It appears that

the iron horseshoe was invented in Gaul about the

time of Julius Caesar, and taken to Britain soon

afterward.

3. Wind Power

Primitive man may have hoisted crude sails of

skins on his rafts of canoes, for there is clear

evidence of the migration of peoples over wide

stretches of ocean long before 3000 BC. The ships

of Egypt, Phoenix, and Greece were driven partly by

a large square sail of mid ships and partly by

oars. The war gallery, in which a greater degree of

maneuverability was needed, had narrower lines and

depended more on oars than did the trading vessels.

In other parts of the world the original dugoutcanoe developed into different kinds of watercraft.

In the North Sea a ship that was sharp at both

ends, like canoe, developed, where as the

Mediterranean type of vessel had a rounded stern.

In the Pacific, through rafts remained in the use

in some regions, a completely different type of

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ocean-going watercraft, the outrigger canoe,

developed. In Chinese waters at junk appeared.

Mediterranean ships were all carvel built, that

is, the planks were placed side by side like the

boards on a floor, and the cracks between the

boards made watertight with tar. The ships of the

North Sea, however, were made of overlapping

planks, or clinker built. North Sea ships had only

one steering oar, placed on the steer board, or

starboard, quarter, whereas the Mediterranean ships

had two steering oars one on each side of the

stern. The rudder that is used for steering inmodern ships did not make its appearance until

about 1200 A.D.

A great aid to sea transportation reached

Europe about 1300 AD in the form of the ships

compass, a device first known among Chinese sailors

and then transmitted by the Arabs. An important

improvement in ship-building took place about 1450

AD with the development of the three-master ship.

Thereafter the story of sea transportation is

largely the story of the conquest of the whole

globe by the three-mastered skin.

4. Roads and Vehicles

The Romans brought road building to its highest

point of perfection in ancient times. The Roman

road network reached a total of about 50,000 mi.

(80,000 km.), with feeder roads branching outfrom the main highways. The roads were costly

because Roman road engineers assumed that deep

foundations, formed by layer after of heavy stones

were necessary to make roads that would carry heavy

traffic for many years. This theory was not

completely abandoned until John L. Mc Adam

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perfected the macadamized road in England about

1815. Realizing that dry native soil would support

any weight. Mc Adam made the surface of his roadscompletely watertight and curved so that main would

run off them as off a roof. He did this pounding

and rolling a layer of small stones into a hard

surface. This road remained the best that could be

devised until the rubber tires of the last country.

Significant improvement of road vehicle began

with the adoption of coach spring about 1650. In

the mid 18th century English roads were so bad that

coaches could average only about 4 mph (6.4 km/h),and the mail was usually carried by boys on horses

for delivering the mail. The first mail coach run

in March 1785 and by 1800 the English mail coach

system was in full swing.

Canals, railways, and steamboats. The

improvement in roads, in the horses and in coaches

had solved the problem of fast transportation of

passengers and light freight, but there still

remained the problem of heavy transportation. This

problem was met first by the development of canals

and later by railroads.

In 1761, the Duke of Bridgewater arranged with

an engineer, Jones Brindley, to Manchester, 7 mi.

(11 km) away. As a result the price of coal

dropped by half, while still allowing the Duke

plenty of profit on his investment. Brindleys

success led to England, in particular was coveredby a network of canals. The first American canal,

opened in 1825, connected Lake Erie with the Hudson

River at Albany.

English canals fell into decay with the coming

of the railroad. William Mardlock and Richard

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Trevthick had made early types of locomotives

before 1800. But it was George Stephenson who

pushed through the final stages of the fullydeveloped railway locomotive. Stephenson built his

first model in 1814 for use in hauling trucks of

coal. The first railroad was the Stockton and

Darlington Line, begun in 1825. The second, the

Liver Pool and Manchester, followed in 1829.

At first, it was certain that these early crude

locomotive should be more satisfactory than horses.

It was assumed that locomotives would not be able

to haul heavy loads up an incline, since thewheels, it was thought, would spin without gripping

the rails. This theory was later found to be false,

but only after long sections of English lines, at

great cost, had been made as near horizontal as

possible.

By 1840 the English railways had put nearly all

the main coaching companies out of business, and

the road ceased to be an important factor in inland

transportation until the automobile era began about

1900. In the USA, the Baltimore & Ohio Railroad

Company began work on the first American railroad

in 1828. Construction of Canadas first railroad,

the Champlain and St. Lawrence, began in 1832.

The development of the steamboat proceeded

simultaneously with the development of the steam

locomotive. Here the steam engine was to impart a

rotary motion to paddle wheels. The firstsuccessful steamboat journey in USA was made by

Robert Fultons Clermont up to the Hudson River in

1807. By 1811 the first steamboat appeared on the

Ohio River, inaugurating the great steam boating

era on the inland waterways.

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5. The Bicycle

The bicycle is important in the history of

transportation, not only in its own right, but

because of the part of bicycle industry played as a

nursery of automobile builders. One of ancestors of

the modern bicycle was the Hob Horse, or Dandy

Horse, which could be seen on the English

macadamized roads after 1818. The wheels of these

machines were of wood, with tires of iron, and the

riders pushed themselves along with their feet onthe ground. There was a steady improvement in the

bicycle throughout the 19th century, until the

safety bicycle, with pneumatic tires, at last

appeared. Some of the earliest automobiles ran on

four bicycle wheels.

7. The Automobile

In England for some times after 1800 it seemed

that the future of mechanical road transportation

with the steam carriage. Stem traction engines were

a familiar sight on many roads throughout the world

toward the end of the 19th century.

The future of mechanical road transport,

however, lay with vehicle driven by the internal

combustion engine, the invention of which usually

attributed to the Frenchman Etiene Lenoir. By 1865

there were 400 Lenoir gas engines in France doingsuch light work as cutting chaff and driving of the

modern automobile when he put toward the invention

of the modern automobile when he put one of this as

engines in a carriage and drove around his factory.

This carriage also made a journey of some miles to

Paris.

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Two German inventors, Nicolaus Otto and

Gottlieb Daimler, also pioneered the manufacture ofgas engines, and Daimler later became a successful

manufacturer of automobiles. At the same time a

small array of inventors was at work in various

countries on the development of early types of

automobiles. The invention of the pneumatic

bicycle tire by Scott, John Boyd Dunlop in 1988

gave a tremendous impetus to this early work.

8. Air Transport

Not until the development of the internal

combustion engine can the era of air transportation

be said to have begun. Men were making balloon and

flights, however, or more than a century before

Wilbur and Orville Wright made their famous first

flight at Kitty Hawk, North Carolina, USA, in 1903.

The progress of air transportation was hastened by

World Wars I and II. An important advances in

aircraft propulsion occurred with the invention of

the jet engine. Until this invention practically

every great advance in transportation techniques

had been the result of the application of the

principle of rotary motion.

The jet engine has made possible speeds that

could never had been attained by the rotary action

of the air-crew is effective only in the earths

atmosphere. The rocket, however is effective

beyond the earths atmosphere, and its developmenthas opened up the era of space exploration and

interplanetary travel.

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The Word Traffic

The word traffic originates from Greco-Roman

word Trafico with reference to the movement of

people that dates back from the dawns of history:

from the domesticated horse-drawn wheels to

horseless carriage. The Greek originally called

the system Trafriga after the early horse-drawn

chariots with spoked wheels.

If savants of Rome are to be believed, there is

no dispute that the word Trafico is a Greco-Romanword, but the word traffic was created from the

famous Trafalgar Square, the hub-center of

commerce and culture in the heart of London.

But in Latin, the word traffic is denominated as

Commercium with reference to the movement and

control of goods in transit from un-wheeled axle to

horseless carriage. This intellectual discourse of

discoveries only reinforced the universal dictum

that traffic refers to the movement of people and

goods and not vehicle. Perhaps this is the missing

jewels in the systematic strategies of traffic

management.

Legal Basis in the Traffic Management Process

1. Republic Act No. 4136, The Land

Transportation Code of the Philippines, asAmended.

2. Republic Act No. 7160, The Act Providing

for a Local Government Code of 1991.

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Definition of Traffic Management

Traffic Management presupposes an understanding

of the motivation behind the behavior of motorist,

commuters, and pedestrians. Any attempt to

redirect their behavior without understanding will

not be able to effectively solve the traffic

problems.

Innovative Policy to Address Traffic Problems

1. Reiterate the use of public roadways as a

matter of privilege and not as matter of right.

2. All forms of privatization of public

thoroughfares should be controlled.

3. Must encourage the development of a mass

transport system and de-emphasize the use of

private vehicles.

The Main Tasks Required to Improve Traffic

Management

1. Consolidate the single road use handbook,

all the traffic laws, rules and regulations,

guidelines, must be revised and issued yearly.

2. Ensure that each traffic user is trainedand disciplined.

3. Revalidate all drivers licenses and all

certificates of vehicle registration.

4. Clear the road network of obstructions.

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5. Streamlining the traffic adjudication

process.

6. Fast-track the shift to a mass transit

system.

7. Complete the basic framework of the road

network.

Causes of Traffic Congestion

1. Immediate

Congestion grows most obviously and at alarming

rate primarily in areas experiencing rapid

population growth, which cause parallel increase in

the ownership and u se of automotive vehicles.

2. Long-Term

Commuting during certain hours add considerably to

traffic congestion. The so-called rush-hours are

concentrated in relatively short period each day,

mainly from 7:00 to 9:00 in the morning and from

5:00 to 7:00 in the evening, when most people rush

to and from work.

Strategies in Resolving Traffic Congestion

1. Supply-Side Strategy

Expansion of the peak-hour carrying capacity of an

areas transportation system seems to be the most

intuitively obvious response to greater congestion

can be implemented through diverse means: 1)

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Building more roads or widening existing ones in

areas that have experienced rapid growth; and 2)

making transportation systems more efficient.

2. Demand Side

One of the demand-side tactics transportation

economist advocate is peak-hour pricing. This is

achieved by charging all drivers who use crowded

highways during peak-hours a toll large enough to

discourage many others from doing so.

Another demand-side strategy is shifting peak-hourtrips to other times of the day. This may be

achieved by staggering work hours among different

organizations, adopting flextime policies or even

four-day weeks. Changing week hours would slightly

more effective at reducing congestion in the

morning.

The 5Es of Traffic Management

The concepts of traffic although originated in

Egypt are being claimed by other countries. While

its sophistication and the principle of the 3Es

Enforcement, Engineering, and Education was

developed in Rome, there is however, no historical

impediment that the original traffic philosophy

began in Egypt.

By historical perspective, 3Es was dovetailedin Egypt, chiseled in Rome and upstaged in the

U.S., by time and event. It was an indispensable

ingredient in the traffic gems, mined from years

after years of event.

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At present time, it is a clinical autopsy on

traffic management to dissect and create new ideas

that can bury the corpse of 3Es concept to givebirth to the 4th E Environment, and the 5th E

Economics. Giving birth to the additional 2Es,

traffic management now a day deals with 5Es, i.e.,

enforcement, engineering, education, environment

and economics.

Definition of Traffic Enforcement

It is an action taken by the traffic lawenforcers and the count to compel obedience to

traffic laws and ordinances, regulating the

movement and use of motor vehicle for the purpose

of creating deterrence to unlawful behavior by all

potential violators.

The Five (5) Essential Steps of Traffic Enforcement

1. Detection

Wholly a traffic law enforcers responsibility

and entails in looking for the defects in the

behavior of motorist, pedestrians, vehicles,

equipment, and roadway condition. However, requires

knowledge of law on the part of the traffic law

enforcers.

2. Apprehension

Wholly a traffic law enforcers responsibility

where the traffic law enforcers are required to

take action at once to prevent continued and future

violations.

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3. Prosecution

While this is a court function the traffic law

enforcers also provides corresponding influence

through preparation and introduction of evidence or

by close contact with the prosecuting officer.

4. Adjudication

While this is obviously a court function, the

traffic law enforcers provides influence on thisstep by acting as witness to the prosecution or

supplying additional evidences, this step

determines the guilt or innocence of the

respondents.

5. Penalization

The court imposes the penalty upon the

respondents. The penalty is greatly influenced by

previous records of conviction as provided by the

traffic law enforcers.

Major Elements of Traffic Law Enforcement

Activities

1. Enforcement System

Consist of legislation, police and the courts.Legislation defines and specifies correct or

incorrect road user behavior. Traffic law

enforcers and the courts is charged with the

responsibility of insuring that these laws are

adhered to.

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2. Road User System

Includes pedestrians, pedal cyclist, drivers,

passengers and others.

3. Traffic System

Consist of the entire road and vehicle complex.

Kinds of Traffic Law Enforcers Action

1. Arrest

It is enforcement actions which consist of

taking person into custody for the purpose of

holding or detaining him to answer a charge of law

violation before a court. Arrest is made when the:

1) the offense committed is serious; 2) detention

is necessary to avoid continued violation; and 3)

there is reasonable doubt that the violator will

not appear in court.

2. Traffic Citation

A means of having violators appear in court,

without physical arrest. Kinds of which are: 1)

Traffic Citation Ticket; 2) Temporary Operators

Permit; 3) Traffic Warning.

An enforcement action which does not

contemplate possible assessment of penalty by the

court or otherwise as a results of warning alone.

It is of three (3) types: 1) visual; 2) verbal; and

3) written

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Definition of Traffic Supervision

It is defined as keeping informed on streets,

highways within existing regulations to make their

use safe and expeditious.

Definition of Traffic Control

The control of vehicles or pedestrian at a

certain point or area by mechanical means, fixedobjects or manpower.

Major Causes of Traffic Jams

1. Multiple Head-on Collisions

Statistics tell us that the impact of any head-

on collision on the highway is beyond comprehension

for flesh and debris littered on the roadways. An

even experienced investigator is sometimes shocked

at the gory sight of the tragedy and may cause his

investigation in snail pace. This undue delay is

an invitation to traffic jams.

2. Flooded Area

The cause may be attributed to clog drainage

network or engineering failure to consider theinterplay of ecology in road constructions.

3. Bridged Collapsed

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Rampaging flood due to heavy downpour may cause

soil erosion of the river bank and in the process

weak bridge foundation, collapsed.

4. Landslide

Denudation of the forest, causes to loosen the

earth surface and as a consequence of torrential

rains may cause the earth and boulders to fall or

landslide.

5. Overturned Fourty-Footer Van

When detach may go wayward or uncontrollable

and rest across the street, constricting of fully

block the road to traffic. Its removal can only be

effected by a ten-toner towing machine.

6. Logs Rolled from the Trailer Trucks

A freak accident but may precipitate at traffic

jam if strewn across the road for its removal

cannot be made manually but only either to heavy

crane or bulldozer.

7. Oil Leaks

From tanker that covers three to five kilometer

oil leaks on cemented pavement could create

pandemonium traffic accidents that would give rise

to suits and counter-suits.

Instant Solutions to Traffic Jams

1. One Way Traffic

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An important tool to decongest the traffic

standstill until such time that the density of the

vehicle is reduced to accommodate the regular flow.

2. Counter-Flow Traffic

A temporary scheme when the volume of one lane

direction is so saturated that the movement of the

vehicles is practically nil, while the flow of the

opposites direction is light in scale, the only

solution under the circumstances if to counter-

flow.

3. Re-Routing of Traffic

When the density of vehicles in opposite

directions has reached such proportion tantamount

to a complete halt of movement, the only

alternatives is to adapt the re-routing of traffic

to secondary streets.

4. Diverting of Traffic

When the magnitude of traffic conflicts was on

vast scales: flooded area, landslide, bridge

collapsed and other contingencies, the only

feasible solution is diversion of traffic. The

difference between re-routing and diverting of

traffic, the latter is large in scope, long and

tedious in perspective.

5. To Open Private Roads for Temporary Access

Most often than not, residents of exclusive

subdivisions vigorously opposed the use of their

roads under the many real or imaginary pretext.

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But the objection can be assailed under the police

power of the state.

6. Stop-and-Go Signal

One of the secrets to unlock the monstrous

traffic gridlock is for one lane to move. Unless

this can be affected the problem would be

aggravated by the passage of time. The scheme

should only be implemented when other alternativeis seemingly un-adaptable.

7. X-Option

When the situation is so grave that solutions

are nowhere in sight, traffic enforcers should

adapt the multi-options as the viable approach to

solve the traffic orgy.

Traffic Engineering

Forecasting of future traffic and evaluating

the magnitude of street hazards through traffic

engineering is not as simple as measuring the

height, length and width of the cube.

Taking the prevailing attitudes and atmosphere

of publics impatience towards the strange-shapedof geometrical road design is more than meet the

eye. Public attitude has turned corrosively

negative for they believed they were betrayed by

promises for safe travel. This is the unspoken

sentiment of the public in view of agonizing twists

and turns of events. But what is worse, if we hear

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no voices, except silent murmurs of the despised

citizenry.

To escape from frustrations and wants, traffic

engineering must know all and forestall all effects

whether natural or man-made calamities. A formula

that will dance to the tune of new technology, new

horizon and new vistas to open the floodgate of

traffic engineering in contemporary times.

Definition of Traffic Engineering

Traffic Engineering is the science of:

1. Measuring traffic and travel.

2. The study of basic laws relative to the

traffic law and generations.

3. The application of this knowledge to the

professional practice of planning, deciding, and

operating traffic system to achieve safe and

efficient transportation and goods.

Geometric Design

A traffic engineering phraseology for

forecasting future traffic demand on target year

for road design. It is indicator dictated by

development of land use, industry, economy, andpopulation component.

Many countries vary on the target year for road

design on account of topography, development,

environment, cultural idiosyncrasies and road

factors. From the viewpoint of traffic

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engineering, the maximum life for road design is

within the range of 15 to 25 years, and the

prevailing range now is 20 years.

The geometric design of road in order to have a

reliable forecast for viable projection of traffic

demand is determined by traffic generators, among

others: developmental plan, economic index, zoning

schemes, land use and population growth.

The hourly, daily and annual volume of traffic

is graphically taken into consideration for road

designs. Corollary, to maximize safe and speed,the physical features of the highway is considered

in the formulation of the design speed to determine

road design and safety factors.

Functions of Traffic Engineering

1. Fact finding, surveys and recommendations

of traffic rules and regulations.

2. Supervisions and maintenance to the

application of traffic control devices.

3. Planning of traffic regulations.

Road Check Objectives

The objectives of road check are to detect andinspect the following:

1. Faulty vehicle equipment.

2. Registration and licensing of violations.

3. Intoxicated drivers.

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4. The load or cargo of commercial

transportation vehicle for load weight.

Considerations Taken When Conducting Road Checks

1. Minimum delay to motorist.

2. Thorough checking procedure.

3. Protection, safety of both motorists andpolice officers.

4. Timing, location and frequency.

Kinds of Traffic Control Devices

1. Traffic Signals

2. Road Signs

3. Road Markings

Functional Classification of Traffic Control

Devices

1. Regulatory Devices

It is having an authority of the law and impose

precise requirement upon the action of the road

user.

2. Warning Devices

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Are used to inform the road user of potentially

hazardous roadway conditions or unusual traffic

movements which are not readily apparent to passingtraffic.

3. Guiding Devices

Are employed simply to inform the road user of

route, destination, and other pertinent

information.

Primordial Purpose of Signal Control

1. To minimize traffic conflicts and time

delay.

2. To reduce vehicular accident.

3. To economize manpower.

Classes of Traffic Signs

1. Danger Warning Signs

These signs are intended to warn road users of

danger that lies ahead of its nature.

2. Regulatory Signs

These are intended to warn road users of

special obligations, restrictions or prohibition

with which they must comply. It is subdivided into

three categories:

1) Priority Signs

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These are signs intended to regulate

priority over a particular road section or roadwayintersection.

2) Prohibitory or Restrictive Signs

These signs can be used on specified

section of the road which will be easily seen by

motorist to indicate regulation which is

prohibitive or restrictive in nature.

3) Mandatory Signs

These signs are intended to guide road

users of special rules in which they must comply

for the safety, convenience and smooth flow of

traffic.

3. Informative Signs

These signs are intended to guide road users

while traveling, and are subdivided into:

1) Advance Signs

These are the names and distances of the

principal destination or destination served by the

intersecting roads.

2) Direction Signs

Unlike the advance direction signs, direction

signs shall be placed at the right of intersection

to show the direction and destination of a route.

Direction signs are different from mandatory signs,

since these signs gave only information as to

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direction and destination of place, while mandatory

signs require compliance.

3) Place Identification Signs

These may be used to show the frontier between

two countries or for the purpose of showing the

beginning and/or end of built-up areas.

4) Confirmatory Signs

These are used to confirm the direction of a

road. They shall bear the names of one or more

places. Where distances are shown, the figures

expressing them shall be placed after the name of

the locality.

5) Other signs providing useful information

to guide drivers.

6) Other signs indicating facilities for road

users.

Road Classifications

1. According to Political Subdivision

1) National Roads

The main road as conduit system with a

right of way from 20 meters to 120 meters.

2) Provincial roads

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The linkages between two municipalities

with right of way from 15 meters to 60 meters.

3) City Roads

The inter-link between municipalities and

within city proper with right of way of 15 meters.

4) Municipal Roads

All roads within the town proper with

right of way of not less than 120 meters.

5) Barangay Roads

Commonly called farm to market road with

right of way of not less than 2 meters.

2. According to Functions

1) Feeder Roads

Intended for farm-to-market roads.

2) Local Collector Roads

Intended to collect traffic from feeder

road to municipal road.

3) Major Collector Roads

Intended as major arteries to collect

inter-locality traffic to provincial road.

4) Major Highway

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Serves as main artery that caters on big

volumes of vehicular traffic on national roadway.

5) Expressway

A through traffic for free-flow of

vehicular movement.

6) Tunnel Road

A passage of wide section cut through a

hill or sea to shorten circuitous roadway.

7) Subway

An underground conduct running entirely

under the ground for fast travel route of

commuters.

8) Skyway

A modern urban system of roadway above

street level for free-flow traffic.

3. According to Topographical Terrain

1) Flat Road

2) Zigzag Road

3) Steep-Hill Climbing Road

4) Down-Hill Road

5) Winding Road

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6) Mountainous Road

7) Roller Coaster Road

Boulevards and Avenues Distinguished

Many are in the quandary as to the whale of

difference between avenue and boulevard.

There is an international acceptance that they

are both national roads. Both are broadthoroughfares, but boulevard is more prestigious in

sophistication than an avenue. Often than not,

boulevard is teeming with grassplots and tress

along the center, the sidewalk and oftentimes,

boulevard is with lighted post in highly urban

centers of the world. It is for this reason that

the boulevard is named after great men and heroes.

Sidewalks

It is an integral part of the roadways in any

metropolitan cities of the worldit is also one of

the specie of geometric designs. Sidewalk is the

answer for the safety of pedestrian safety. Thus,

sidewalk reduced the hazards of pedestrian to the

slender yardstick of traffic engineering.

Intersections

Today, urban cities of the world walk on 2-legs

man and machine. But the continuity of its

locomotion depends upon the inter-link of

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connecting road network at intersection to meet

traffic demand.

The plan and design of intersection is based on

traffic component, traffic volume, speed, traffic

distribution, canalizations of traffic accidents

and future traffic demand.

Kinds of Intersections

1. Three-Leg Intersection

1) T-Type

2) Y-Type

2. Four-Leg Type

1) Right Angle

2) Oblique

3. Multi-Leg Intersection

4. Rotary Intersection

Fundamental Principles of Intersections

1. Intersection should be avoided on curve

section, bridge, attaching part, cutting, and

crest, near entrance of tunnel and besides railroad

crossing.

2. Intersection should not be greater than 4

legs. While 4-leg intersection is better than 3-

leg intersection, however, if 5-leg intersection is

unavoidable it must be used only as an exit.

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3. Two roads should not intersect as a small

angle. Intersecting at less than 60 degrees makes

it difficult for drivers to turn at acute angle andin effect constrict his visibility particularly 10-

wheeler trucks.

4. Distances between two intersections should

be based on land use of density of road network.

Factors that determine the minimum distance of two

intersectionsqueue length by the control of

traffic signals, length of weaving section, length

of turn and limit of drivers concentration.

Definition of Filter Lane

The word filter in its literal meaning is to

control or constrict the movement of vehicle as it

passes through the lane designated therefore. This

traffic engineering design is to prevent traffic

gridlock at the intersection when turning left at

the green arrow filter signal.

Channelization

A traffic engineering terminology that

separates or regulates the conflict of traffic

movements into a definite paths of travel by means

of traffic island or pavement markings for the safe

and orderly travels of both man and machine.

Principles of Channelization

1. It reduces the area of conflict in large

paved intersection. In view of uncontrolled

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vehicle and pedestrian movements it creates

congestions and accidents.

2. The speed of traffic stream at the

intersection may be controlled by the curvature

employed in the bending of the roadways. Thus the

minor flows will be sent to conform to the main

traffic stream.

3. Likewise, the speed of traffic stream at

the intersection may be controlled by funneling. A

scheme which not only controls the speed of

entering vehicles but prevents overtaking andpassing in a conflict area.

4. It blocks prohibited turns. To divert

traffic streams, islands may be employed to

encourage drivers in the strict observance of

prohibited turns.

5. It provides refuge for turning, and

crossing vehicles. Adequate shadowing provides

safe refuge for waiting vehicle to cross or enter

and uncontrolled traffic stream.

6. It is essentially required for an

effective signal control at intersection with

complex turning movement.

7. It provides location for the installation

of traffic control devices at the intersection of

multi lane roadways with complex turning movements.

Traffic Education

Traffic education is the crowning jewel of

traffic management, an abstract architect of social

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life and an unyielding master of mans destiny on

the roadways.

As one of the 5Es of traffic management, it is

a priceless gem in total gamut of social order on

the road, likened to an oasis in a desert of

roadways. Therefore, traffic education must be

free and there must no economic barrier to its

acquisition.

In sum, what is needed are men of courage and

vision to initiate reforms and craft a more viable

formula that will shape the future quality oftraffic education.

Considerations to Road Discipline

Considered in this light, what has to change is

not culture, but the heart and mind towards road

discipline. A vivid proof that discipline remains

in shaping force of our vision and it towers like

mountain above other values. Safe to say, what is

needed now is to harness the armed conscience of

the silent majority to cease to be silent and join

the crusade against the scourge of moral decay on

the roadways. For only by its fruits can we know

the tree.

Traffic Education as a Merchandize

Traffic education by itself is merchandize

difficult to sell, not only because it is

expensive, but there are varying shades of

acceptability among the masses. And the seeds of

reforms are not always sowed on fertile soil. But

without social transformation, all traffic laws,

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even with punitive sanctions will be ineffective in

the crusade to institute reforms. For there is no

way of inculcating new moral order into theconsciousness of uneducated people.

Mistaken Notion About Traffic Education

Many have the mistaken notion that education is

only the acquisition of knowledge, the accumulation

of facts of learning of information by rote.

Traffic education is more than just the absorption

of information and learning of skills. Trafficeducation is the making of a whole person, of a

human and humane being, of civilized or cultured

individual inculcation in the youth of norms, moral

and ethical behavior, good manners and right

conduct.

Complexity of Traffic Education

Traffic education is too complex to be covered

only by limited topics or by the volume of

scholarly books for it encompasses vast

intellectual novelties that cannot just be left to

the market forces of experts but to the

articulation of the academe. Having put the idea

forward, it must be pursued to the end to reap the

expected dividends. This is not the utopian

demand, but a challenge for a better future and new

order on the roadways.

Only with moral climate can we open new

frontiers and move toward new horizon and learn the

lessons of the past for the present and the wisdom

to know the difference that past failures should

not foreclose future successes.

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Environment

Environment is not a mere creative philosophy,

but a new vision with unique force that could

reshape the world of traffic management. In word

of scholar, environment is a single phrase that is

an anathema to purist and idealist but by word to

ecologist. It reflects the bountiful blessings of

nature in prestige form: tress in greenest state

and seas abounding with fishes and marine life,

until man like carpetbaggers, wrought wantondamages to contemporary damages.

It is about time that environment be

institutionalized as a pillar of traffic

management. For one of the real tragedies of

traffic administrator today is the failure of

traffic titans to incorporate environment as the 4th

E of traffic management. If the past experience is

any guide, there are just too many variables that

affect the system whose common denominator of

solutions is equated to environment. It is the

system which destroys and it is the system which

saves.

External Factor

Driving is not a theoretical fixture. In

driving, the attitudinal norms of drivers arevaried, subject to the tempo of time and space,

cultural relativism, values and environment.

Behavioral patterns of drivers are disturbed by

the external factor of environmental elements on

the roadways decreases the drivers skills, keen

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perception and sound judgment. If drivers are

unaware of these unwanted variables while cruising

the highways, they are courting dangers and thus,prone to accidents. The following are the common

external factors:

1. Heat

It is a form of energy which causes the body to

rise in temperature, to fuse and to evaporate that

can excite emotionally the drivers skill while

behind the wheels.

2. Storm

This atmosphere disturbance with strong winds

and rains is usually accompanied by thunder and

lightning. With these ambient atmosphere and

environmental mal-conditions, the drive on wheels

is affected physiologically and emotionally. At

the height of heavy downpour and torrential rains

the visual range is limited impairing his effective

control of the vehicle.

Under these adverse conditions, the driver must

have stock of theoretical and practical knowledge

in driving for experience alone is not sufficient

to measure proficiency.

3. Fog

Unlike the cloud which is visible mass abovethe earths surface, fog is condensed water vapor

in cloudlike masses that forms close to the ground.

This feature is its distinctive difference.

Sometimes fog is caused by masses of floating

materials of either dust or smoke that obscures the

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visibility of the driver to less than 1, 100 yards.

Irritated by this environmental phenomenon,

judgment of the driver is substantially affectednot knowing what to do and what not to do. Against

those backdrops, driver should be guided not by the

dictates of the heart but by the wisdom of the

mind.

In countries where the weather condition is

foggy, vehicle should be equipped with a yellow for

lights. Although there is negative finding that

yellow light does not totally penetrate the foggy

weather, however, in the absence of viablealternative, the usability of yellow fog lights has

its universal acceptance.

Internal Factor

Internal factors is a behavioral pattern of man

which appears early in life. Many voices are

advocating the hypothesis of relationship between

stress and environment. Even doctors failed to

identify the true traits of the individual which

most often do not surface in his personality test.

While today there is commonality of consensus

that internal factors reacts on the chemistry of

environment, still a need arises for savants to the

further flex their intellectual muscles to act as

arbiter of the present and future destiny of the

drivers tailored on human dimensions.

The following are the most common identifiableinternal factors that cause road accidents:

1. Personality

It is in this internal factor that distinctly

distinguishes an individual driver from other

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drivers in relation to environment. The qualities

of the driver constitute his personal being and

social traits. His personality is best tested whenconfronted by the greatest odds of the

environmental factors.

2. Character

From the beginning of time, the complex

characters as to behavior and habits, attitudes and

interests and personal philosophy in life

distinguishes a particular driver from the other.

Another scientific marvel is the discovery of a

detectable organism that is the result pf thepresence of gene or group of genes that

differentiates one driver from the other.

Driver may probably have developed the tenacity

for survival, but his character may yield to

massive onslaught of a violent environment, and

thus brook peril and misfortunes while behind the

wheels. Drivers by way of omissions succumb to

human lapses and adversarial curse of the

environment which may end in road accident.

3. Epilepsy

The word epilepsy is derived from the Greek

word, epilambanein,meaning to take hold. It is

defined as a chronic nervous disorder of the human

brain affecting the mans consciousness and

muscular control with various degrees of severity.

It may be congenital of brain damage caused bytumor, injury, glandular imbalance or toxic

substances and may result in convulsions or lost of

consciousness.

4. Sleeping Sickness

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A chronic disease e occurring in tropical

countries like Africa, this is caused by parasites

trypanosoma gambiense and rhodosiense andcarried by flies.

It causes fever, physical and mental lethargy,

and very often death. It also occurs in Central

Africa and commonly called encyphalitis

lethargica.

What is pathetic is that this incidence becomes

common to drivers while cruising along the mountain

trails and forested areas, when stung by theseinsects, the tendency of the drivers body function

is to diminish or at worst, cease. This in effect

is an ominous sign that danger lurks ahead as the

driver may lose control off the vehicle which may

ultimately end in road mishap or may flung into the

deep ravine.

Threats to Environment

As one travels on the highways or roadways,

probably they are unmindful of the following

environmental threats to man and nature:

1. Greenhouse Effect

Scientifically, the greenhouse effect is a

natural phenomenon that makes earth habitable,

without which the earth would be frozen like Marsand other celestial bodies.

2. Ozone Depletion

The disastrous effect of ozone depletion is the

uncontrolled emission of ultra-violet light and not

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climatic change. Ozone per se is an allotropic

form of oxygen created when oxygen molecules are

bombarded with ultra-violet rays from the sun. Ifthe ozone layer fails to absorb the ultra violet

rays from passing the earths surface, the ultra-

violet radiations causes skin cancer and cataracts.

3. World-wide Effect

Change in UV-B radiation may have been caused

by a chemical reaction as a consequence of gases

spewed into the atmosphere by volcano eruption.

Other scientific findings have reported thatmeasurements by satellite and by high-altitude

balloons detected record of thinning of ozone due

to volcanic eruption.

4. Effect in Climate

The transition fro the Ice Age to warmer

weather in which our civilization flourished took

only a few decades, and the climate could change as

quickly as possible.

Motor Vehicle its Effects to Environment

In so many words the major environmental

effects of the use of motor vehicles are air and

noise pollution:

1. Air Pollution

The most lethal effect of motor vehicle is the

pollution caused by engine exhaust. The finding

shows that the carbon monoxide emission has higher

percentage in highly urbanized areas.

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Air pollution is usually measured in terms of

concentration of pollutants over time, such as

parts per million of air per hour or in terms ofpollution to vehicle usage in grams per vehicle-

mile.

The primary pollutants in motor vehicles

exhausts are carbon monoxide (CO); hydro-carbons

(HC); nitrogen oxides (NO); mostly nitrogen

dioxide; lead (Pb), and particulate matter.

Likewise, larger engines emit considerable amounts

of sulfur oxides (SO), mostly sulfur dioxide.

2. Noise Pollution

Less dangerous than air pollutions, but

admittedly more vexing and annoying, is the problem

of vehicular noise. Of several sources of

vehicular noise, the cars tire-roadway interaction

and truck exhaust noise have been identified as the

primary cause of noise pollution.

Noise levels are measured in decibels (dB) on a

logarithmic, rather than in arithmetic scales.

Study showed that a decrease of only 10dB would

whisper at 5 feet (1.5 m) will register about 34

dB; the interior of a quiet office will average 55

dB; and the sound level at the side of an

expressway may be as high as 90 dB.

The effects of traffic noise on human seem to

be more psychological than physiological. Severalstudies have pointed to annoyance as being the

widespread effect. There is no question that

highway noises alone can causer hearing damage, but

the effects of noise annoyance on behavior and

mental health cannot be disregarded.

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Pollutants Caused by Motor Vehicles

The following pollutants are known to cause

damage to vegetation and thus, to man:

1. Ozone

As a component of the photochemical complex,

ozone is considered to one of the most damaging air

pollutants to vegetation. Ozone produces acharacteristics fleck of stipple on the upper

surfaces of sensitive plants. Prolonged exposure

or high concentrations will cause complete tissue

collapse.

2. Peroxyacyl Nitrate (PAN)

PAN can produce the characteristics systems of

glazing or bronzing of the lower surfaces of the

younger leaves of sensitive plants. Even a low

concentrations, i.e., 0.01 ppm for 8 hours, PAN

produces chlorosis and early senescence.

3. Hydrocarbons

Ethylene is the only hydrocarbon from vehicle

exhaust that is known to cause a variety of

symptoms in many plants, including early

senescence, chronic injury, flower and fruit drop,and growth suppression.

4. Carbon Monoxide

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The effects produced by carbon monoxide are

similar to those of ethylene; however, the

concentrations must be very high.

5. Petrol Additives

Lead, nickel, boron and manganese are known to

be toxic to plants to accumulate in sufficient

quantities. The additives may accumulate in plant

tissue without injuring the vegetation, but they

may prove toxic to animals and human being who

obtain food from these plants.

The Laws of Nature as Applied to Motor Vehicles

Some of known laws of nature that affects the

skill of the driver and efficiency of the machine

in relation to environment are as follows:

1. Inertia

It is the first law of motion as espoused by an

undisputed man of science.

1) Inertia of Rest

Any object at rest will remain at rest

unless no external factor forced it to move. This

is the reason why it is difficult to push stalled

vehicle at rest.

2) Inertia of Motion

Any object in motion will constantly move

in straight line unless other forces intervene to

change its speed or course. This explains why a

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stalled vehicle when in motion finds no greater

obstacle to gain momentum of speed. This law of

motion gives birth to the development of seat beltand other accessories to cushion the impact from

the abrupt change from inertia of rest to inertia

of motion.

2. Centrifugal Force

A scientific term of force that pushes a moving

object in circular motion away from the center. To

better understand its effects, if a ball is tied to

a string and whirled around in fast speed, thepulling of the ball in circular path away from the

center is known as centrifugal force. And is the

string breaks from the ball it shall not follow the

circular path of motion but will follow the

direction where the string breaks.

Similarly, a car negotiating a curved road is

subject to same force as the ball and string model.

The car is to the ball and the string to the

friction between the tire and the road. Thus, if

the friction breaks the car will skid or careen-off

the roadways.

To cushion the effect of centrifugal force on

curve roads, man has developed three kinds of road

surfaces on curves, these are:

1) Crowned Curve

Is designated to better serve the drainage

system but not necessarily the safety factor,

especially on high speed. The curve according to

studies, press the car against the road surface, in

effect lessening the friction between the tires and

pavements.

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2) Flat Curve

According to authorities it offers no

resistance to skidding onward, hence, dangerous at

high speed.

3) Bunked Curve

Of the three, bunked curve is unquestionablythe best for the inertia of motionit is

counteracted by the nature of the road on the car.

3. Gravity

Simply stated, it is a kind of force that tends

to pull all objects to the center of earth. To the

layman, the effect of gravity can be better noticed

when a car is negotiating an uphill trend. Because

of the gravity, it needs to accelerate its power to

counter-balance the pull.

But in downhill course, driver should be extra-

cautious because of the braking force of the engine

pull and gravity pull are on the same direction and

must be counteracted, otherwise the car may careen

off the roadway if uncontrolled.

It should be noted that the center of gravityof an object is the point where its weight is

evenly balance. This is the rationale why the car

designsthe center of gravity is taken into

consideration to forestall a turn-turtle when the

car suddenly changes its course while in motion.

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4. Kinetic Energy

It is an established fact that anything thatmoves possesses this kind of energy. It is safe to

conclude, therefore, that any energy of motion is

denominated as kinetic energy.

To better appreciate its importance, a car

traveling at higher speed demands a period of time

before it can totally stop, because the greater the

speed of moving object, the greater it is kinetic

energy. Unless the driver is conversant of the

implication of this law of nature, he is at perilto meet an accident on sudden brake.

5. Friction

It is that kind of natural force that causes

resistance of one surface against the other when it

comes to contact. This could be better observed

when a car either moves or starts.

According to studies, the increase or decrease

of friction on the pavements depends whether the

road is dry or wet. However, there are three

factors that could reduce the road-wheel friction.

1) Weather condition.

2) Worn tire thread.

3) Bumpy road.

6. Force of Impact

The amount of force when two objects collide is

known as force of impact and it expressed in

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pounds. This force according to authorities is

determined by:

1) The speed of the moving object and the

angle at which they collide.

2) The weight of the object or objects.

3) The distance within which an object is

stopped after the initial impact.

Economics

Economic, oils the wheels of traffic. Time

has come that the economics of traffic be rescued

from the barred waste of wrong perceptions:

traffic and economics are strange bedfellows and

their unity in diversity is a mere fiction.

Experts must have an open mind not just revite4d to

the narrow confines of 3Es of traffic and refuse

to look beyond the costly illusion of its advocate.

These are decisions that might be charting

unpopular course but hope to give shapes and sinews

to empty illusions of the past and to look forward

to the new complexion of the present system with

new vision of the future: the crowning of the 5th E

of traffic, economics.

This is not a choice of necessity but signs of

time. For decades, scholarly studies have noted the

fast decline of the 3Es philosophy from thepedestal of respect and the patterns is traceable

to the shifting demands around the world. The fact

that there is indeed a mountain of books in the

fields of 3Es does not alter the unseen forces of

recession.

Economic-Traffic Interactions

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Human gregariousness craves for many wants and

seems to admit no satisfaction: problems begin.But all of these wants are not free and can only be

acquired at the altar of sacrifice: most goods are

scarce. Goods are not necessarily chosen to

satisfy basic wants either directly or indirectly.

Capital goods are produced for industries to

produce goods for consumption. The element of

choice on how to satisfy the present wants for the

future wants.

Even with modern infrastructure as analternative solution to the ills of traffic will

put to naught if the resources is scarce, a

classical balancing interaction of traffic and

economics.

Economics as the 5th Es of Traffic

Non-incorporations of economics as the 5th Es

of traffic is complex pattern that traffic taipans

would find it difficult to defend. As long as

these traditional thinking experts refuse to veer

away from the old-school to the modern traffic

ideology, then we are creating more problems than

solutions on the road.

This argument is broadened further by the

studies that technocrats are guided and influenced

by their own self interest in shocking disregard ofthe changing world behavior on the traffic system.

Traffic Accident Investigation

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Successful traffic accident investigation

requires considerable basic background knowledge.

To know what question to ask, and what to look for,you must also have some fundamental ideas about

accidents and their causes. To avoid wasting time

and making mistakes, especially during the urgent

activities at the scene of an accident, you need to

plan what you are going to do and to continually

revise your plan as you proceed.

What is a Traffic Accident

A traffic accident is that occurrence in a

sequence of events which usually produces

unintended injury, death, or property damage, or a

traffic accident is something happened that was

not expected. Criminal charges arising out of

traffic accidents are mostly due to negligence on

the part of the driver. Negligence means failure

to take proper care.

There are two (2) main kinds:

1. Errors of Commission

Where a person does thing that he should

not have done.

2. Errors of Omission

Where a person does not do something heshould have done.

Classification of Traffic Accidents

1. Motor-Vehicle Traffic Accident

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Is any motor-vehicle accident occurring on a

traffic way, for example, the ordinary collision ofmotor vehicles on a highway?

2. Motor-Vehicle Non Traffic Accident

Is any motor vehicle accident which occurs

entirely in any place other than a traffic way, for

example, a motor vehicle accident on a farm or in a

private driveway?

3. Non Motor-Vehicle Traffic Accident

Is any accident occurring on a traffic way

involving persons using the traffic way for travel

or transportation, but not involving a motor

vehicle in motion, for example, collision between a

pedestrian and a bicyclist on a sidewalk?

Definition of Motor Vehicle

It is every device which is self-propelled and

every vehicle which is propelled by electric power

obtained from overhead trolley wires, but not

operated upon rails.

Definition of Traffic Way

It is the entire width between the boundary

lines of every way or place of which any part isopen to the use of public for purposes of vehicular

traffic as a matter of right or custom.

Chain of Events of a Traffic Accident

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1. Perception of Hazard

Is the seeing, feeling, or hearing andunderstanding the unusual and unexpected movement

or condition that could be taken as a sign of the

accident about to happen.

2. Encroachment

Is the movement into the path assigned to

another traffic unit, perhaps the most important

encroachment is crossing a center or barrier line.

Another is entering a crosswalk when it is

occupied. Pedestrians can encroach on the pathassigned to motor vehicles.

3. Leaving the Roadway

Is the moving off the roadway, Roadway is

that portion of traffic way which is improved,

designed, or ordinarily used for vehicular travel

exclusive of the shoulder. The event takes place

when one wheel of the vehicle may leave the

roadway. A vehicle may leave the roadway on the

left as well as on the right side.

4. Leaving the Road

Is the moving off the road and shoulder, if

any, this may mean going into the ditch or over a

curb. The event takes place when one wheel of the

vehicle climbs the curb or goes off the shoulder,

5. Initial Contact

Is the first accidental touching of an object

collides with by a traffic unit in motion, before

this, there is no force between the objects

colliding, and afterwards there is force.

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1. Running off the road.

2. Non-collision on the road.

3. Collision on the road.

Classification of Accident According to Severity

1. Property Damage

It is nay motor vehicle accident in which thereis no injury to any person but damage to the motor

vehicle, to other property including injury to

animals.

2. Non-Fatal

It is any motor vehicle accident that results

in injuries other than fatal to one or more

persons. The injuries maybe as follows:

1) Fatal Injury

It is an injury that results in death

within 12 months of the motor vehicle traffic

accident.

2) Serious Visible Injury

It is a bleeding wound, distorted member,or any condition that requires the victim to be

carried from the scene of the accident. Consider

the injury to be visible if symptoms are present

even though the injury itself is not visible.

3) Minor Visible Injury

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It is an abrasion, bruise, swelling,

limping, or obviously painful movement.

4) Non-Visible Injury

It is complaint of pain without visible

signs of injury; or momentary unconsciousness.

3. Fatal

It is any motor vehicle accident that resultsin fatal injuries to one or more persons.

Crucial Events

It is used instead of key event to characterize

what occurs to each traffic unit individually

rather than to the whole accident and with

reference to the available path rather than the

entire road.

Crucial Events in a Traffic Accident

1. Leaving the available path, not the same

as running of the road.

2. Turning over in the path without

collision.

3. Other non-collision in path.

4. Collision with non-traffic object in or

adjacent to the path.

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5. Collision with other traffic unit in the

path, not marked vehicle.

The Three Points in Traffic Accident

1. Point of Possible Perception

It is the place and time at which the unusual

or unexpected movement or condition could have been

perceived by a normal person. This point always

comes at or before the point of perception. Delayin perception or perception time between the point

of possible perception and the actual perception.

If the hazard is actually perceived as soon as

nearly as possible, perception is said to be

prompt. Maximum delay of perception occurs when

the traffic unit does not sense a hazard until hit

it.

The perception point and the point of possible

perception are used mainly in trying to discover

and evaluate contributions of drivers and

pedestrian to accidents. Did the driver do

anything or fail to do anything before the

perception point that contributed to his

difficulty. Inattention is probably the most

common contribution of driers to their delayed

perception; but speed is a common contributor to

accidents before perception point. The perception

point is particularly useful in trying to discoverwhat the driver or pedestrian did or should have

done but did not do to avoid the accident or to

make it less serious.

2. Point of No Escape

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Is that place and time after or beyond which

the accident cannot be prevented by the traffic

unit under consideration. Nothing the driver orpedestrian can do will save him from this point on,

although he still may be able to mitigate the

accidentfor example, by slowing down as much as

possible before a collision. Sometimes the point

of no escape and point of perception are the same.

Sometimes the point of no escape comes before the

point of perception, for example when a persons

attention is diverted until just before the crash.

Often the point of no escape comes after the point

of perception. This circumstance generallyindicates faulty judgment on the part of the driver

in his attempt to prevent the impending accident.

3. Point of Impact

It is term which, although widely used in

connection with traffic accidents, does not seem to

have very precise meaning. Impact generally means

the same thing as collision but it also means the

force involved. Point of impact is sometimes used

to mean the same as point of initial contact,

sometimes used to mean the same as point of maximum

engagement and sometimes center of force. Because

the term has varied meanings, other more specific

terms are preferable.

Technical Aspects of Traffic Accident Investigation

The traffic accident investigator should know

how to make proper sketch of an accident with

correct measurements of all the important data. He

should know how to photograph the scene of the

accident properly, to show the important facts. He

should know what kind of physical evidence to look

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for in hit-and-run cases. He must know how to get

the facts, records the facts correctly, and then

figure out what happened in order to help theprosecutor present the case in court.

Definition of Attributes

An attribute is any inherent characteristics of

a traffic way, a vehicle or a person making a trip

on a traffic way that affects the probability of a

traffic accident.

Purposes of Traffic Accident Investigation

1. Everyone involved is curious about causes

and circumstances of the accident.

2. Police are also interested in finding out

whether there is enough evidence of law violation

in the accident to take enforcement action.

3. Insurance agencies and adjusters want to

determine negligence on the part of the drivers

involved in the accident so that damage claims can

be properly adjusted.

4. Government officials and other concerned

authorities want specific information about

accidents to know better how to prevent future

accidents.

Basic Steps in Traffic Accident Investigation

1. Go to the scene as quickly as possible.

2. Park correctly to avoid further collision

and facilitate traffic flow.

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3. Assess the situation and call for whatever

assistance is necessary.

4. Care to injured and protect their personal

property.

5. Protect the scene against additional

collision.

6. Locate drivers and establish identities.

7. Interview drivers, participants andwitnesses.

8. Note and record physical conditions at the

scene, locations of vehicles and evidence.

9. Take photograph when possible

10. Test and inspect the vehicles when

applicable.

11. Arrest or cite violators when applicable.

12. Have the scene cleared up.

13. Follow-up at the hospital.

14. Notify relative and survivors.

15. Prepare reports.

Levels of Activity in Accident Investigation

1. Reporting

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2. At-scene Investigation

3. Technical Preparation

4. Professional Reconstruction

5. Cause Analysis

Hit-and-Run Investigation

The search for physical evidence at the scene

of a hit-and-run accident must be done properly andquickly because it is not possible to close-off and

guard the scene of this kind of crime? The roads

must be cleared to permit ordinary flow of traffic

as soon as possible? Another problem is that

passing vehicles will crush of blow away important

pieces of small physical evidence. The following

are the good ways of searching the scene of a hit-

and-run accident:

1. Look over the ground at what seems to be

the point of collision.

2. Follow the path that the vehicle took in

leaving the scene to find out if it left tire

prints in the soft dirt, or where parts of the

vehicle or broken glass fell off as is drove away.

3. Study the objects the vehicle has struck

to see if there is a transfer of physical evidencelike paint.

4. Look for things that may have spilled from

the vehicle.

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The investigator should collect all materials

found at the scene of the crime which cannot

satisfactorily explained. Broken parts of themotor vehicle are the most important physical

evidence in hit-and-run accidents. When the broken

parts match parts still on the car, this is a good

positive identification. Broke parts are more

important than damaged parts. Part of a broken

bumper of door handle is better than a damaged

hubcap.

Proving Driving

In all case of traffic offense, intoxicated

driving or hit-and-run, the first and most

important thing that must be proved is that the

accused person was driving the car at the time of

the offense. This can be done either by eye

witnesses or by physical evidence. But it must be

proved. The investigator must not assume that the

owner of the vehicle was the person actually

driving it.

Nature of Common Hit-and-Run Cases

1. Run over of pedestrian crossing on the

roadway or crosswalk.

2. Sideswiped of pedestrian on the sidewalk

or road shoulders.

3. Collided with a moving vehicle while

overtaking on same direction.

4. Collided with a moving vehicle while

overtaking on opposite direction.

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5. Damaged parked vehicle along the roadside

and parking areas.

6. Crushed police road blocks.

7. Bumped stray animal on the roadway.

Technical Preparation

Delayed traffic accident data collection and

organization for study and interpretation. Thedata collected are essentially factual. Technical

preparation includes making additional measurements

and photographs, preparing maps and diagrams,

simple speed estimates, matching damage areas, and

making experiments to obtain specific data. It is

third level of traffic accident.

Triangulation

A method of locating a spot in the area by

measurements from two or more reference points, the

location of which are identical for future

reference. Compare with coordinates.

Determining Speed from Skid marks

One of the most common problems in accidentinvestigation is: How fast was he going? it is

difficult question to answer, but speeds in excess

of the legal limits are important to the police,

because they must decide if the driver did his best

to avoid accidents. The criminalist cannot

determine exactly how fast a vehicle was traveling,

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but he can make a very good estimate by

mathematical calculations based on the skid marks

left by a vehicle before the collision. It isimportant that the field investigator take correct

and accurate measurements to help the criminalist

make correct calculations.

Skid Marks

Skid marks are marks lefts on the road by tires

that are not moving because the brakes are applied

strongly enough to lock the wheels. There are two(2) kinds of skid marks:

1) made by a car going straight ahead, and

2) made by a car going sideways.

The second type is commonly called scuffs.

It is important not to confuse skid marks with tire

prints. Tire prints indicate that the wheel was

still turning. Tire prints should not be used in

calculating speed. To make an accurate estimate of

speed, it is important that the marks of all four

tires are obtained.

A car is always going faster than the speed

calculated from skid marks, because in addition to

losing speed in sliding as shown by the skid marks,

the car also losses its speed in one or more of the

following ways:

1. Skid marks do not happen until the tire

slides far enough to get hot enough to smear the

rubber on the paving.

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2. The total distance of the skid marks

cannot be seen because the car hits something

before stopping.

3. Some braking action occurs before the skid

marks appear.

4. The brakes are not put on hard enough to

lack the wheels.

In accidents with pedestrian, the skid marks

are most reliable because there is nothing to stop

the forward movement of the car. In a collisionaccident, the amount of damage to the cars must be

considered in determining the reliability of speed

from skid marks.

Scuffmarks

A friction mark on pavement made by a tire

which is both rotating and slipping, acceleration

scuff yaw marks, flat tire marks.

Skip-Skid

A braking skid marks interrupted at frequent

regular intervals, the skid mark made by a bouncing

wheel on which brakes keep the wheel from turning,

compare with gap skid.

Gap Skid

A braking skid marks which interrupted by

release and reapplication of brakes or which

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terminates by release of brakes before collision,

compare with skip skid.

Flip

The movement of vehicle without touching the

ground from a place where its forward velocity is

suddenly stopped by an object such as curbs or

furrow-in below its center of mass with the result

that the ensuing rotation lifts vehicle off the

ground. A flip is usually sidewise, but if it isendwise, it is spoken as a vault.

Length of Vehicle

The investigator sometimes makes mistakes of

determining the speed from the total length of the

skid marks he finds. Remember that the beginning

and end of the skid marks may include both the

front and rear wheels of the car and unless it is

possible to measure each wheel base, distance

between the middle of the hubcap of the front wheel

to the middle of the hubcap of the back wheel,

should be subtracted from the total length of the

skid marks.

Grade or Slope

Grade or slope means the steepness of a hill

and is important in calculating speed from skid

marks, because a car going downhill take longer to

stop than a car going uphill, or slope is the

number of meters the road rises for each meter of

level distance along the road. The resulting

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number is less than 0.1 except for very steep hill.

It can be measured by using traffic template or

with an ordinary carpenters level. Put thecarpenter level on the road with one end uphill and

the other down. Raise the down hill end until the

bubble centers. Hold the level in that position

while you measure the distance from the bottom of

the level down the road. Divide this distance by

the length of the level. For example, if the level

is one meter long and lower end is one centimeter

off the ground the grade would be 0.01.

Calculation of Speed from Skid marks

There are charts and tables and even special

measuring devices from which the speed can be

calculated from the skid mark. The criminalistic

investigator, however, should understand the exact

mathematical formula which the speed is calculated

because he may ask by the judge in court to explain

how he arrived at his estimate. The formula is not

difficult and the only hard part is determining the

square root. This can be easily done by means of a

set of tables or a slide rule, but in the range of

measurement with which the investigator is

concerned, there is a simple formula for

determining square root that is sufficiently

accurate for the purpose.

Find the nearest number to your measurement

which has an even square. Example: 4, 9, 25, 36,64, 81, 100, etc. If the number in your

calculation is 30, for example, the closest number

is 25 which is only 5 numbers away rather than 36,

which is 6 numbers away. Since 5 X 5 equals 25,

divide your number by 5, then average the result by

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the divisor, and you will get a square root

sufficiently accurate for the purpose.

Formula:

S = 15.9 d X (F + g)

-

Where:

S = speed in kilometer per hour

d = slide-to-stop distance in meters

g = grade or slope

F = drag factor

or

S = 5.5 d X (F + g)

-

Where:

S = speed in miles per hour

d = slide-to-stop distance in meters

g = grade or slope

F = drag factor

Example:

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A vehicle going down hill with a slope of 0.15

and a drag factor of 0.70, leaves a skid marks of

20.6 meters. What is the speed of the vehicle?

1. SPEED = 15.9 20.6 X (0.70 - 0.15)

The vehicle is going down hill, so the grade is

negative and is subtracted.

2. SPEED = 15.9 20.6 X 0.55

= 15.9 11.33

The nearest whole number whose square is

closest to 11.33 is 3 (3 X 3 = 9).

3. 11.33/3 = 3.78

4. 3.78 + 3 = 6.78/2 = 3.39

5. SPEED = 15.9 X 3.39 = 53.90 km/hr

All calculations are resolved in favor of the

driver, so:

6. SPEED = 54 km/hr

Factor

Any circumstances contributing to a resultwithout which the result could have not occurred;

an element which is necessary to produce the

result, but not by itself, sufficient, operational

factor and conditional factor.

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Operational Factor

Functional failure of the highwaytransportation system that contribute to the cause

of traffic accident. The failures may be

malfunctions or perception, decisions, or

performance in trip planning driving strategy, or

evasive tactics.

Sequential Factor

Factors which must be present at the same time

to contribute to the cause of an accident,generally operational factors.

Simultaneous Factor

Factors which must present at the same time to

contribute to the cause of accident, generally

condition factor.

Drag Factors

It is a number representing the acceleration or

deceleration of vehicle or other body as decimal

fraction of the acceleration of gravity, the

horizontal force needed to produce acceleration in

the same direction divided by the weight of the

body to which the force is applied. When a vehicle

slides with all the wheels locked, the coefficientof friction and drag factor have the same value.

Co-Efficient of Friction

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The number representing the resistance to

sliding of two surfaces in contact; the drag factor

of a vehicle or other object sliding on a roadwayor other surfaced required to keep an object

sliding on that surface in motion, divided by the

force of the object against that surface, measured

in pounds per pounds, often designated by the Greek

letter Mu.

Reaction Time

The time from perception to reaction.

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ANSWERS TO REVIEW QUESTIONS IN TRAFFIC

MANAGEMENT & ACCIDENT INVESTIGATION

===========================================================

1. B 26. C 51. C 76. A

2. C 27. C 52. A 77. B

3. A 28. A 53. B 78. A

4. A 29. A 54. D 79. B

5. B 30. C 55. C 80. D

6. A 31. A 56. A 81. C

7. B 32. B 57. C 82. A

8. B 33. A 58. A 83. C

9. B 34. D 59. B 84. B

10. A 35. C 60. D 85. A

11. D 36. D 61. C 86. B

12. A 37. A 62. C 87. D

13. C 38. B 63. B 88. A

14. D 39. D 64. B 89. A

15. D 40. C 65. A 90. B

16. B 41. A 66. B 91. C

17. C 42. B 67. D 92. D

18. C 43. B 68. A 93. D

19. D 44. D 69. A 94. C

20. D 45. B 70. B 95. D

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