Dolmar MS-250.4 Manuel D'instructions page 24

EMISSION COMPLIANCE PERIOD
For handheld 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.
Category C=50 hours, B=125 hours, and A=300 hours.
Air Index and durability period information
The Air Index Information hang-tag for this engine is provided in accordance
with the California emission regulations.
The graphical representation of the Air Index on the hang-tag shows the
emissions performance of this engine, and can be used to compare the
emissions performance with other available engines.
The lower the Air Index, the less pollution.
Note: Remove the hang-tag before operating the engine.
The Emissions Durability Period referred to on the hang-tag indicates the
number of operating hours for which the engine has been shown to meet the
California emission requirements.
Descriptive term
Moderate
Intermediate
Extended
Applicable to Emissions Durability Period
50hours (0-80 cc, inclusive)
125hours (0-80 cc, inclusive)
300hours (0-80 cc, inclusive)
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