Emissions Durability Period and Air
Index Information On Your Engine
Emissions Label
Engines that are certified to meet the California Air Resources Board (CARB) Tier 2 Emission Standards must display information regarding the Emissions Durability Period and Air Index.The engine manufacturer makes this information available to the consumer on emission labels.
The Emissions Durability Period describes the number of hours of actual running time for which the engine is certified to be emissions compliant, assuming proper maintenance in accordance with the Operating & Maintenance Instructions.The following categories are used:
Moderate: Engine is certified to be emission compliant for 125 hours of actual engine running time.
Intermediate: Engine is certified to be emission compliant for 250 hours of actual engine running time.
Extended: Engine is certified to be emission compliant for 500 hours of actual engine running time.
For example, a typical
The Air Index is a calculated number describing the relative level of emissions for a specific engine family.The lower the Air Index, the cleaner the engine.This information is displayed in graphical form on the emisions label.
Emissions Compliance Period On Engine Emissions Compliance Label
After July 1, 2000 certain Briggs & Stratton engines will be certified to meet the United States Environmental Protection Agency (USEPA) Phase 2 emission standards. For phase 2 certified engines, the Emissions Compliance Period referred to on the Emissions Compliance label indicates the number of operating hours for which the engine has been shown to meet Federal emission requirements. For engines less than 225 cc displacement, Category C = 125 hours, B = 250 hours and A = 500 hours. For engines of 225 cc or more, Category C = 250 hours, B = 500 hours and A = 1000 hours.
This engine has an intermediate rating with and Air Index of 3. The EPA Emissions compliance period is Category C.The diplacement of these engines is 305 cc.
Below is a generic representation of the emission label typically found on a certified engine.