[Code of Federal Regulations]
[Title 40, Volume 29]
[Revised as of July 1, 2007]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR600.109-78]

[Page 886-887]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 600_FUEL ECONOMY OF MOTOR VEHICLES--Table of Contents
 
    Subpart B_Fuel Economy Regulations for 1978 and Later Model Year 
                       Automobiles_Test Procedures
 
Sec. 600.109-78  EPA driving cycles.

    (a) The driving cycle to be utilized for generation of the city fuel 
economy

[[Page 887]]

data is prescribed in Sec. 86.115 of this chapter.
    (b) The driving cycle to be utilized for generation of the highway 
fuel economy data is specified in this paragraph.
    (1) The Highway Fuel Economy Driving Schedule is set forth in 
appendix I to this part. The driving schedule is defined by a smooth 
trace drawn through the specified speed versus time relationships.
    (2) The speed tolerance at any given time on the dynamometer driving 
schedule specified in appendix I, or as printed on a driver's aid chart 
approved by the Administrator, when conducted to meet the requirements 
of paragraph (b) of Sec. 600.111 is defined by upper and lower limits. 
The upper limit is 2 mph higher than the highest point on trace within 1 
second of the given time. The lower limit is 2 mph lower than the lowest 
point on the trace within 1 second of the given time. Speed variations 
greater than the tolerances (such as may occur during gear changes) are 
acceptable provided they occur for less than 2 seconds on any occasion. 
Speeds lower than those prescribed are acceptable provided the vehicle 
is operated at maximum available power during such occurrences.
    (3) A graphic representation of the range of acceptable speed 
tolerances is found in paragraph (c) of Sec. 86.115 of this chapter.