[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: 40CFR610.34]

[Page 1005]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 610_FUEL ECONOMY RETROFIT DEVICES--Table of Contents
 
                   Subpart C_Test Requirement Criteria
 
Sec. 610.34  Special test conditions.

    If the Administrator determines that a device may have potentially 
detrimental effects on the operation of a vehicle when operated in 
ambient conditions outside the range specified in 40 CFR part 86, or if 
the device manufacturer claims a fuel economy improvement in such 
conditions, additional tests may be performed. These tests will 
determine whether the device will significantly limit the operational 
usefulness of the vehicle and will assess the claimed fuel economy 
benefit.
    (a) Extreme temperatures. As required by the Administrator, tests 
will be conducted at extreme ambient temperature conditions to determine 
the effect due to devices (e.g. engine heaters) for which fuel economy 
improvements at extreme temperatures are made. For other devices it may 
be necessary to determine whether the cold starting and driving 
capability of device-equipped vehicles is affected sufficiently to make 
them dangerous, or whether fuel economy characteristics at extreme 
temperatures are significantly worse than before the device was 
installed.
    (b) High altitude. Devices for which specific claims of improved 
fuel economy at high altitude are made may be tested using the 
procedures in subpart D, at altitudes above 4000 feet. For other 
devices, testing at high altitude may be necessary for determining 
whether a device will make the vehicle less useful or efficient when 
operated at various altitudes. The Administrator will determine when 
such testing is required.