Compared too many other sources of pollution; the automobile rates quite low on the scale. The problem is scale; when hundreds or thousands of cars are packing the roads to maximum capacity, the cumulative effects of all these vehicles becomes enormous. When you are sitting in a traffic cue and you are looking at the exhausts in Petersfield, rising to join all the other smog producing contaminates, just think for a moment where that exhaust has been in the seconds prior to your seeing evidence of it.
There is no doubt that automobiles are much cleaner than they were 40 or 50 years ago. New environmental regulations have forced automobile manufacturers to clean up their products and no doubt they have. One of the reasons for continued high levels of pollution is that everyone tends to drive more than was the norm years ago.
Nevertheless, the exhausts in Petersfield have evolved considerably. What are the components of a typical exhaust system?
The typical exhaust system is made up of a number of pipes, all of different shapes. The pipes are designed to fit with each other and to conform to a specific component of the undercarriage which the pipe must go over, under or around. For example, the pipe must be bent to go up and over the rear axle of the car. Every pipe is part of a continuous system which is designed to move the exhaust gasses from the engine to the rear of the car where they are exhausted into the atmosphere. There may be pipes that split into twin paths, pipes of this nature may be found next to the exhaust manifold and again where the system can split into a dual exhaust system.
It may appear to be inefficient to have so many different pipes rather than just one pipe. Each section serves a purpose; they have to go from the exhaust manifold to the catalytic converter and from there through more pipes to the silencer. As each section of the Car exhausts in Petersfield can become damaged or perhaps rust out prematurely, it is also less expensive to replace only one short section rather than the entire pipe or to replace a worn out silencer without disturbing the balance of the system.
