Gallon for gallon — or, given the size of lawnmower tanks, quart for quart — the 2006 lawn mower engines contribute 93 times more smog-forming emissions than 2006 cars, according to the California Air Resources Board. In California, lawn mowers provided more than 2 percent of the smog-forming pollution from all engines.
But as soon as air pollution regulators suggested adding a golf-ball-size catalytic converter to the lawn mower, they found themselves in one of their fiercest political battles of the past decade.
On one side, the federal Environmental Protection Agency and state regulators in California. On the other, the largest lawn and garden equipment maker in the country and a powerful Republican senator. And in the middle, the six million or so lawn mowers shipped to retailers every year.
For older regulators, it is a replay of Detroit’s initial resistance to those who wanted clean up car exhaust by installing catalytic converters, which pull smog-forming chemicals and carbon monoxide out of the exhaust.
“I think it’s very analogous to what happened in the 70’s,” said Robert Cross, chief of the California air agency’s Mobile Source Control Division. “The arguments are all the same.”