Nevada to enforce diesel exhaust opacity limits

| 1/2/2003

The Nevada Department of Motor Vehicles will begin enforcing stricter opacity standards on exhaust from heavy-duty diesel trucks Jan. 1, 2003, according to a statement. The standards apply in all counties to all trucks and buses with a gross vehicle weight rating of at least 8,500 pounds.

The department says the new limits are more in line with the Environmental Protection Agency's opacity standards, recommended by most neighboring states. The Nevada State Environmental Commission adopted the tiered limits in October, but the state DMV had issued only verbal courtesy warnings through the end of the year.

The department says its goal is voluntary compliance. Fines are waived on a first offense if the vehicle is repaired within 45 days.

Exhaust from trucks with engines manufactured in 1991 or later must block no more than 40 percent of the light passing through it. Engines made between 1977 and 1990 are held to a standard of 55 percent opacity. Engines made between 1970 and 1976 must meet an opacity standard of 70 percent.

Engine families exempted by the California Air Resources Board are also exempt in Nevada. Previously, all trucks with engines 1977 or newer were held to the 70 percent standard.

The department conducts random testing at weigh stations and on the roadside. For more information, visit the Nevada DMV Web site at