8 May 2003

The California Air Resources Board (ARB) has verified a diesel oxidation catalyst system from Donaldson as a “Level 1” device, bringing at least 25% reduction in particulate matter (PM) emission when used on selected nonroad (off-road) diesel engines. It is the first emissions control device verified by the ARB for use on nonroad engines, including those used in yard tractors, large lift trucks, top picks, side picks and gantry cranes.

The Donaldson system includes a DCM diesel oxidation catalyst muffler with 6000 Series catalyst formulation, combined with Donaldson Spiracle™ closed loop crankcase filtration system. It can be used with standard California diesel or lower sulfur fuel strategy. The system may be used for a number of four-stroke, turbocharged diesel engines ranging from 150 to 600 hp from Case, Detroit Diesel, Caterpillar, Komatsu, and Cummins.

Donaldson received an ARB verification for highway engines in November 2002. Systems verified for highway engines included various combinations of the DCM catalyst muffler with or without the Spiracle™ closed loop crankcase filtration system. Two types of catalyst were used: the more active 6100 Series catalyst suitable for ultra low sulfur fuel applications, and the sulfate-suppressed 6000 Series, suitable for use with all commercial fuels.

All emissions control systems for use in California diesel retrofit programs require formal ARB verification. PM emissions reduction devices can be verified as “Level 1”, of 25% PM emission reduction (this category intended for diesel oxidation catalysts); Level 2, of 50% PM emission reduction; or Level 3, of 85% PM emission reduction (mostly particulate filters).

ARB verification letter
ARB verified systems

Source: California ARB