REPORT 1

AIR POLLUTION BY VEHICLES

Introduction

Nothing is more basic than air. Nothing more essential to life. We breathe about 60 pounds of air everyday. That's 760 tons in a lifetime. Over 625 million breaths.

Our earth is the only known place in the entire universe which is capable of supporting life due to its unique atmosphere. Air is one of five essential component for life i.e. air, water, food, heat & light. For survival of life it is important that air pollution due to various pollutant's adversely human, animal & plant life must be avoided at any cost. Air pollution is defined as change in natural quality & composition of air due to presence of various polluting factor's which are responsible to cause adverse effects on living organisms existing on earth.

Whether industrial, vehicular, or consumer-based, this pollution is real, and dangerous - - despite increases in warnings about air pollution and legislation efforts to control it.

Hydrocarbon pollutants also escape inio the air through fuel evaporation - evaporative losses can account for a majority of the total hydrocarbon pollution from current model cars on hot days when ozone levels are highest.

Diesel fuel is a multi-purpose petroleum fuel used in trucks, trains, boats, buses, planes, heavy machinery and.off-road vehicles. It also remains one of the largest sources of fine particle air pollution, which has serious health impacts. Besides particles or soot, Diesel-fueled engines also emit nitrogen oxides that form ground level ozone ("smog").

2. Reasons of Air Pollution

The air pollutants may include solid particles liquid droplets or gases & may be derived naturally or artificially due to human activities. The air pollutants are classified in to different categories depending on their origin, state of matter & chemical composition.

In cities across the globe, the personal automobile is the single greatest polluter, as emissions from a billion vehicles on the road add up to a planet-wide problem. Driving a private car is a typical citizen's most air polluting activity.

There are many substances in the air which may impair the health of plants and animals (including humans), or reduce visibility. These arise both from natural processes and human activity. Substances not naturally found in the air or at greater concentrations or in different locations from usual are referred to as 'pollutants'.

Pollutants can be classified as either primary or secondary. Primary pollutants are substances directly produced by a process, such as ash from a volcanic eruption or the carbon monoxide gas from a motor vehicle exhaust.

Secondary pollutants are not emitted. Rather, they form in the air when primary pollutants react or interact. An important example of a secondary pollutant is ozone—one of the many secondary pollutants that make up photochemical smog.

Note that some pollutants may be both primary and secondary: that is, they are both emitted directly and formed from other primary pollutants.