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Regulations for Emissions from Vehicles and Engines

Final Rule for Revised Carbon Monoxide (CO) Standard for Class I and II Nonhandheld New Nonroad Phase 1 Small Spark-Ignition Engines

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Rule Summary

This rule revises the Phase 1 carbon monoxide (CO) emission standard for Class I and II new nonroad spark-ignition (SI) engines at or below 19 kilowatts. The action increases the CO standard from 469 grams per kilowatt-hour (g/kW-hr) to 519 g/kW-hr. This action addresses the CO emission difference between oxygenated and nonoxygenated fuels that was not reflected when the Agency previously set the CO standard for these nonhandheld engines in a final rule published July 3, 1995.

Rule History

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