Off-Road Mobile Sources
This page last reviewed June 23, 2015.
The California Clean Air Act (CCAA) mandates the Air Resources Board (ARB) to achieve the maximum degree of emission reductions from all on- and off-road mobile sources in order to attain the state ambient air quality standards. Off-road mobile sources include:
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Small Off-Road Engines and Equipment Less Than 25 Horsepower (Including Lawn and Garden Equipment, and Small Industrial Equipment) |
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Off-Highway Recreational Vehicles (Including Motorcycles and All-Terrain Vehicles) |
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Off-Road Compression Ignition (Diesel) Engines and Equipment (This is for new equipment. If you are looking for the in-use (existing) diesel equipment please go here .) |
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Off-Road Large Spark Ignition (Gasoline and LPG) Engines and Equipment 25 Horsepower and Greater (Including Industrial Equipment, Forklifts, and Portable Generators) See the newly designed website! |
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Airport Ground Support Equipment |
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Cargo Handling Equipment (Diesel) at Ports and Intermodal Rail Yards |
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Locomotives / Railyards |
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Commercial Marine Vessels |
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Commercial Harbor Craft |
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Recreational Marine (Including Personal Water Craft, Ski Boats, Inboards, and Outboards) |
Emission standards have been adopted by ARB for off-road engines included in the above categories. (Updated March 30, 2010.)
- Emission Standards for Small Off-Road Engines and Equipment Less than 25 Horsepower
- Emission Standards for Off-Highway Recreational Vehicles
- Exhaust Emission Standards for Compression Ignition (Diesel) Engines and Equipment
- Emission Standards for Off-Road Large Spark-Ignition Engines and Equipment
- Exhaust Emission Standards for Recreational Marine
Additional ARB
Programs for Off-Road Engines and Equipment
- Off-Road Equipment (In-Use) Control Measure Proposed control measure to reduce diesel particulate matter (PM) emissions from in-use (existing) off-road mobile equipment (used in construction, mining, and industrial operations).
- Off-Road Engine Aftermarket Parts
- ARB Portable Equipment Program
- Emissions Inventory
- Mobile Source Certification Programs
For the 1990 amendments to the federal Clean Air Act preempt California control of emissions from new farm and construction equipment under 175 horsepower, please view a description of preempt equipment. For further information, you may also be interested in visiting the federal non-road engine emissions control program.