[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: 40CFR91.117]

[Page 306]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 91--CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES--Table of 
Contents
 
       Subpart B--Emission Standards and Certification Provisions
 
Sec. 91.117  Certification procedure--service accumulation.

    (a)(1) Any engine required to be tested under Sec. 91.118 must be 
operated with all emission control systems operating properly for a 
period sufficient to stabilize emissions prior to such testing.
    (2) A manufacturer may elect to consider emission levels as 
stabilized when the test engine has accumulated 12 hours of service.
    (b) No maintenance, other than recommended lubrication and filter 
changes, may be performed during service accumulation without the 
Administrator's approval.
    (c) Service accumulation is to be performed in a manner using good 
engineering judgment to ensure that emissions are representative of 
production engines.
    (d) The manufacturer must maintain, and provide to the Administrator 
if requested, records stating the rationale for selecting a service 
accumulation period different than 12 hours and records describing the 
method used to accumulate hours on the test engine(s).