(a) 
         The year of initial applicability of a section is indicated by its section number. The two digits following the hyphen designate the first model year for which a section is effective. A section remains effective until superseded.
 
     
    
        
            Code of Federal Regulations
        
        
            Example:
            
                Section 86.411-78
                 applies to 1978 and subsequent model years until it is superseded. If a § 86.411-81
                 is promulgated it would take effect beginning with 1981; § 86.411-78
                 would apply to years 1978 through 1980.
            
        
    
    
        
        (b) 
         A reference to a section without a year designation implies the appropriate model year.
 
     
    
        
            Code of Federal Regulations
        
        
            Example:
            When considering 1979 vehicles a reference to § 86.411
                 implies § 86.411-79
                . However if no § 86.411-79
                 has been promulgated then § 86.411-78
                 is implied; See paragraph (a) of this section.