| gas emission | 17.18 | Airplanes are used to check gas emissions. | ||
| greenhouse emission | 15.87 | We need to reduce greenhouse gas emissions. | ||
| carbon emission | 3.95 | The forest land absorbs carbon emissions. | ||
| auto emission | 2.50 | One caller even asked about auto emissions. | ||
| vehicle emission | 2.24 | India is to introduce tighter controls on vehicle emissions. | ||
| exhaust emission | 2.17 | From Los Angeles to Athens, city authorities have tried to enact measures to limit exhaust emissions. | ||
| tailpipe emission | 1.91 | All of these items directly affect tailpipe emissions. | ||
| mercury emission | 1.65 | The harm from mercury emissions is still uncertain. | ||
| nitrogen emission | 1.25 | Nitrogen oxide Forty percent of nitrogen oxide emissions in Britain come from vehicles. | ||
| oxide emission | 1.25 | Nitrogen oxide Forty percent of nitrogen oxide emissions in Britain come from vehicles. | ||
| sulphur emission | 1.25 | The report recommends a threefold cut in sulphur emissions. | ||
| diesel emission | 1.12 | The technology for reducing diesel emissions is expensive. | ||
| sulfur emission | 1.05 | In the process, it is reducing sulfur emissions. | ||
| air emission | 0.99 | Two years ago, California moved to crack down on air emissions by SUVs. | ||
| greenhouse-gas emission | 0.99 | But whether the warming results from rising greenhouse-gas emissions is an open question. | ||
| dioxide emission | 0.92 | The result has been a halving of sulphur dioxide emissions in the flue gases.. | ||
| radio emission | 0.86 | Foremost of these is the absence of strong radio emissions from the mystery object. | ||
| fuel emission | 0.79 | Definitely A Priority Pollution from fuel emissions is killing Metro Manilans. | ||
| car emission | 0.72 | It wants even deeper reductions in car emissions than California has proposed. | ||
| pollution emission | 0.66 | They also said a voluntary state program is reducing pollution emissions. |