[Code of Federal Regulations]
[Title 40, Volume 18]
[Revised as of July 1, 2003]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR90.111]

[Page 182]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 90--CONTROL OF EMISSIONS FROM NONROAD SPARK-IGNITION ENGINES AT OR 
BELOW 19 KILOWATTS--Table of Contents
 
       Subpart B--Emission Standards and Certification Provisions
 
Sec. 90.111  Requirement of certification--prohibition of defeat devices.

    (a) An engine may not be equipped with a defeat device.
    (b) For purposes of this section, ``defeat device'' means any 
device, system, or element of design which senses operation outside 
normal emission test conditions and reduces emission control 
effectiveness.
    (1) Defeat device includes any auxiliary emission control device 
(AECD) that reduces the effectiveness of the emission control system 
under conditions which may reasonably be expected to be encountered in 
normal operation and use unless such conditions are included in the test 
procedure.
    (2) Defeat device does not include such items which either operate 
only during engine starting or are necessary to protect the engine (or 
vehicle in which it is installed) against damage or accident during its 
operation.