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CFR > Title 49 - Transportation > SUBTITLE B—Other Regulations Relating to Transportation > CHAPTER V—NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (Parts 501–599) > PART 525—EXEMPTIONS FROM AVERAGE FUEL ECONOMY STANDARDS > 525.9—Duration of exemption.
525.9—Duration of exemption.
An exemption may be granted under this part for not more than three model years.