Why are evaporative emissions a problem?
As tailpipe emissions are reduced due to improved exhaust emission control systems, the hydrocarbons produced by evaporation of the gasoline during distribution, vehicle refuelling, and from the vehicle, become more and more significant. A recent European study found that 40% of man-made volatile organic compounds came from vehicles [43]. Many of the problem hydrocarbons are the aromatics and olefins that have relatively high octane values. Any sensible strategy to reduce smog and toxic emissions will attack evaporative and tailpipe emissions. The health risks to service station workers, who are continuously exposed to refuelling emissions remain a concern [44]. Vehicles will soon be required to trap the refuelling emissions in larger carbon canisters, as well as the normal evaporative emissions that they already capture. This recent decision went in favour of the oil companies, who were opposed by the auto companies. The automobile manufacturers felt the service station should trap th
