This page last reviewed January 9, 2009.

Level 1 verification is for those technologies achieving at least 25 percent or greater reduction in particulate matter. The current verified technologies are listed below. Please read the verification letter(s) below which provide additional information on the applicability of the device for your particular engine. Click on the link below each system for a list of engine families for which devices have been approved (engine series names are provided for reference in most cases). For more detailed information or to purchase the device, please contact the device manufacturer directly. New information will be posted as additional systems are verified. Please check periodically for updates.

The ARB has verified Engine Control System's AZ Purifier and AZ Purimuffler for certain 1991 to 2003 model year, medium heavy-duty Cummins and Navistar/International diesel engines used in on-road applications operating on ultra low sulfur diesel fuel. The verification has been extended to include certain 1973-1993 model year Detroit Diesel Corporation engines used in on-road applications operating on CARB diesel as well as certain Cummins and DDC heavy heavy-duty engines model year 1991-2002, four stroke, used in on-road applications with ultra low sulfur diesel fuel. The AZ Purifier and AZ Purimuffler uses a diesel oxidation catalyst to achieve a 25 percent reduction in particulate matter emissions, qualifying it for a Level 1 verification. Specific engine families and conditions for which AZ Purifier and AZ Purimuffler have been approved may be found in the Executive Order which is listed below.

The ARB has verified the following Engine Control System's AZ Purifier and AZ Purimuffler for 1996 to 2002 model year off-road diesel engines. The application includes off-road equipment at ports, railway yards, and other intermodal / freight operation. The verification requires the use of ultra low sulfur diesel fuel that contains a maximum of 15 ppm sulfur. The Executive Order includes restrictions for this verification. Please click on the link below for a list of engine families for which the system has been verified.

The ARB has verified Donaldson Company, Inc., DCM Diesel Oxidation Catalyst (DOC) Muffler with Series 6400 catalyst formulation alone and with the Spiracle & Trade Closed Crankcase Ventilation (CCV) Filtration System for 1988 through 2002 model year diesel engines used in on-road applications operating on standard CARB or ultra low sulfur diesel fuel. The DCM DOC muffler system uses either a DOC alone or a DOC with a CCV filtration system to achieve a 25 percent reduction in particulate matter emissions qualifying it for a Level 1 verification. Specific engine families and conditions for which the DCM DOC muffler system have been approved may be found in the revised Executive Order.

The ARB verified the Donaldson Company DCM diesel oxidation catalyst (DOC) muffler with 6000 Series catalyst formulation used with California diesel fuel or fuel with a lower sulfur content for model years 1988-1990. These systems will provide at least a 25 percent reduction in PM emissions. Please read the Executive Orders for conditions which these systems have been approved. Specific engine families that apply are listed in the attachment below.

The ARB verified the Donaldson Company DCM diesel oxidation catalyst (DOC) muffler with 6000 Series catalyst formulation and the Donaldson Spiracle; Closed Crankcase Filtration System used with California diesel fuel or fuel with a lower sulfur content for model years 1988-2002. These systems will provide at least a 25 percent reduction in PM emissions. Please read the Executive Orders for conditions which these systems have been approved. Specific engine families that apply are listed in the attachment below.

The ARB has verified the following Donaldson Company products:

(1)    DCM diesel oxidation catalyst (DOC) mufflers with 6000 Series catalyst formulation plus closed loop crankcase with Donaldson Spiracle closed crankcase filtration systems for use in on-road applications.  Please see the attachment below for specified engine families.

(2)   DCM DOC mufflers with 6100 Series catalyst formulation plus closed loop crankcase with Spiracle closed crankcase filtration systems. This system can be used in engines used in on-road applications belonging to the specified engine families in model years 1991-2002.

(3)  DCM mufflers with 6100 Series catalyst formulation alone on 15 ppm or less sulfur fuel. This system can be used in engines used in on-road applications belonging to the specified engine families in model years 1994-2002. Please see the attachment below for specified engine families.

The ARB has verified the following Donaldson Company DCM diesel oxidation catalyst mufflers with 6000 Series catalyst formulation plus closed loop crankcase with Spiracle closed crankcase filtration system with California diesel or lower sulfur fuel strategy. This system may be used for some off-road four-stroke, turbocharged diesel engines ranging from 150 to 600 hp and has been verified to reduce emissions of diesel particulate matter by an average of at least 25 percent. This system may be used in yard tractors, large lift trucks, top picks, side picks and gantry cranes. Please click on the links below for a list of engine families for which the system has been approved:

The ARB has verified the Extengine Transport Systems Advanced Diesel Emission Control (ADEC) system for 1991 to 1995 model year off-road Cummins 5.9-liter diesel engines from 150 to 200 horsepower, which are used in excavators, dozers, and loaders, all with rubber tires, and utility tractor rigs operating on standard CARB or ultra low sulfur diesel fuel. The ADEC system employs a diesel oxidation catalyst, selective catalytic reduction catalyst, and ammonia slip catalyst to achieve a 25 percent reduction in particulate matter emissions, qualifying it for a Level 1 verification. The system also achieves an 80 percent reduction in NOx emissions. Specific conditions for which the ADEC system has been approved may be found in the Executive Order posted below.

The ARB has verified the Vycon REGEN System for rubber-tired gantry (RTG) cranes equipped with Pre-Tier 1 (pre-1996 model year) off-road diesel engines or Tier 1, Tier 2, or Tier 3 certified off-road diesel engines. The Vycon REGEN System is a flywheel based energy storage device that achieves at least 25 percent diesel particulate matter emissions reduction and meets the January 2009 N02 limit, qualifying it for a Level 1 Plus verification. The device also reduces NOx emissions by at least 30 percent. The Executive Order below includes restrictions for this verification.