JSH 06:04 PM, July 12th, 2010

"Mercaptan" is mixed with LPG as its foul odour helps in detecting a leakage. Automobiles and Internal Combustion Engines, burn the fuel (Petrol/Diesel or LPG or CNG etc) to varying degrees depending on the load and acceleration of the vehicle. Eg: when you push the pedal, more fuel is used, less efficiently to gain that speed quickly. That is why an average speed gives you a better mileage rather than quick acceleration, as there is un-burnt fuel which leaves the exhaust. That is why when LPG is used as motor fuel (Autos, Cars etc) you experience an unpleasant stench, specially when it is accelerating, as gas does not get burnt completely. The original use of Mercaptan is for safety reasons in LPG. However, that is specific to kitchen use where the cylinder is stationary and any leak would produce an unpleasant odour. There is three reasons to why Mercantap should _not_ be used in auto-mobiles: 1. Ever noticed that when you smell any specific odour too much, you have a natural ability to get accustomed to it? This ability is same for sweet (perfumes) or unpleasant (garbage) odours. Same is true for Mercaptan. If you are used to such an important odour, the whole safety net falls apart. 2. Auto-mobiles always have (depending on driving habits and engine quality) some amount of un-burnt gases emitting. (This is the reason the whole city of Bangalore smells like a leaking cylinder, especially when u are behind a 3-wheeler auto). In kitchen, the fuel is burnt completely, leaving little/un-detectable trace of mercaptan. 3. There are bound to be side-effects if you inhale Mercaptan all the time in your city. Leaks in cylinders and kitchen are very dangerous and although infrequent, they should be treated as an alarm at every single instance. Such cases do not lead to side-effects. But if you inhale the exhaust emissions of Auto-Waalas all day, and abuse your body like that, it will be detrimental. Note: This is particularly noticeable to new-comers to Bangalore who have not got accustomed. I, for one, tried to find a reason for this. Before allowing to let the people (and Autos) deploy the same kitchen-fuel (LPG) to vehicles, the government regulatory bodies should have done proper home-work. I agree that LPG is an economy fuel and people want to save on fuel costs. Its not the people to blame as not everyone knows these technicalities. But, for the automobile, the LPG should be _without_ mercaptan. The LPG packers might have to do some more research before playing with public health and specially the government who is providing kitchen LPG to Autos at gas-filling stations. Solution: A replacement for Mercaptan (something that has has even lower boiling/combustion point) should be used, so that the un-burnt fuel is rid of it. All automobiles (specially the new ones) have catalyst converters to treat the un-burnt gases. The govt., however, cannot pass on the buck to the automobile manufacturers, because even older car models (more frequently) use LPG as a fuel. Comments, discussion and divergent views on this are really welcome.

JSH 06:14 PM, July 12th, 2010

The original article I published here:
http://jj-public.blogspot.com/2010/07/why-bangalore-city-smells.html