California Air Resources Board

SACRAMENTO – The California Air Resources Board today approved a small engine manufactured by Honda Corp. as the first to meet its 1994 emission standards for utility engines used in lawn, garden and light industrial equipment.

The four-stroke, 188 cc engine is used to power portable generators, small pumps and compressors.

"Limiting pollution from small engines is just as important for clean air as standards for cars, trucks and buses," said James D. Boyd, ARB executive officer. He noted that ARB research as shown some of these engines, particularly two-stroke models, emit up to 50 times more pollution per horsepower than a typical truck engine.

 "Our standards simply require these manufacturers to take the first steps to control their pollution just like other engine makers have been doing for many years," he continued. "Honda should be congratulated for being the first to meet these tough standards, especially since they have done it almost a year before the standards go into effect."

The ARB standards, adopted in late 1990, call for a 46 percent reduction in smog-forming hydrocarbon and nitrogen oxide emissions by 1994 and up to 82 percent by 1999, when carbon monoxide emissions from four-stroke engines must also be cut by 75 percent.

In all, the standards are expected to reduce emissions by about 433 tons per day by the year 2010, as older, more polluting engines are replaced with newer, cleaner models.

In ARB certification of the Honda engine, its combined emissions of hydrocarbon and nitrogen oxide measured 10.1 grams per horsepower, compared to a standard of 12. Its carbon monoxide emissions measured 232 grams per horsepower, compared to a standard of 300.

Manufacturers of four-stroke engines, with overhead valve designs similar to those found in automobiles, were expected to meet the standards by fine-tuning the fuel system, resulting in both lower emissions and improved fuel economy.

Boyd noted that Honda's certification was also noteworthy because of a possible one-year delay in implementing the standards while California waits for the EPA to adopt emission limits which are already overdue for similar types of equipment for farm and construction use.