In a November 2002 final rule, we established the first U.S. emission standards for new snowmobiles. Subsequent litigation regarding that final rule resulted in a court decision which requires us to: remove the oxides of nitrogen (NO<INF>X</INF>) component from the Phase 3 snowmobile standards set to take effect in 2012, and; clarify the evidence and analysis upon which the Phase 3 carbon monoxide (CO) and hydrocarbon (HC) standards were based. In this action, we are removing the NO<INF>X</INF> component from the Phase 3 emission standard calculation. We are deferring action on the 2012 CO and HC emission standards portion of the court's remand to a separate rulemaking action.