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Contact: Kevin R. Malone
1399 American Pacific Dr.
Henderson, NV 89014
Office: (702) 486-1311
Cellular: (702) 499-4278

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FOR IMMEDIATE RELEASE    December 20, 2002
NEWS FROM: Compliance Enforcement Division

Nevada to Enforce Diesel Opacity Limits

Tiered Limits on Smoke Match Surrounding States


The Nevada Department of Motor Vehicles' Compliance Enforcement Division will begin enforcing stricter opacity standards on exhaust from heavy-duty diesel trucks beginning January 1, 2003. The standards apply in all counties to all trucks and buses with a GVWR of 8,500 pounds or greater.

The new limits are more in line with the opacity standards recommended by the EPA and enacted by most neighboring states.  The Nevada State Environmental Commission adopted the tiered limits in October but the Department of Motor Vehicles has issued only verbal courtesy warnings to date. The department's 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 road side. While annual testing is not required for Nevada-based fleets, the department does conduct courtesy inspections at fleet yards. The department uses equipment which adheres to the SAE J1667 standard for opacity measurements adjusted to ambient conditions.

For more information, see the Nevada DMV web site at