The provisions of Secs. 85.1405 through 85.1414 apply to retrofit/rebuild equipment which is to be installed on or used with 1993 and earlier model year urban buses whose engines are rebuilt or replaced after January 1, 1995. For the purposes of Secs. 85.1405 through 85.1414, ``equipment'' includes alternative fuels and fuel additives to be used with urban bus engines.