[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: 40CFR90.103]

[Page 173-176]
 
                   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. 90.103  Exhaust emission standards.

    (a) Exhaust emissions for new Phase 1 and Phase 2 nonroad spark 
ignition engines at or below 19 kilowatts (kW), shall not exceed the 
following levels. Throughout this part, NMHC+NOX standards 
are applicable only to natural gas fueled engines at the option of the 
manufacturer, in lieu of HC+NOX standards.

[[Page 174]]



                                   Table 1--Phase 1 Exhaust Emission Standards
                                            [Grams per kilowatt-hour]
----------------------------------------------------------------------------------------------------------------
                                          Hydrocarbons+oxides
        Engine displacement class             of nitrogen        Hydrocarbons   Carbon monoxide     Oxides of
                                                (HC+NOX)                                          nitrogen (NOX)
----------------------------------------------------------------------------------------------------------------
I.......................................               16.1    ...............              519  ...............
II......................................               13.4    ...............              519  ...............
III.....................................  ...................              295              805             5.36
IV......................................  ...................              241              805             5.36
V.......................................  ...................              161              603             5.36
----------------------------------------------------------------------------------------------------------------


              Table 2--Phase 2 Class I-A, Class I-B, and Class I Engine Exhaust Emission Standards
                                            [grams per kilowatt-hour]
----------------------------------------------------------------------------------------------------------------
          Engine class                HC+NOX         NMHC+NOX           CO                Effective date
----------------------------------------------------------------------------------------------------------------
I...............................            16.1            14.8             610  August 1, 2007; in addition,
                                                                                   any Class I engine family
                                                                                   initially produced on or
                                                                                   after August 1, 2003 must
                                                                                   meet the Phase 2 Class I
                                                                                   standards before they may be
                                                                                   introduced into commerce.
I-A.............................              50                             610  2001 Model Year.
I-B.............................              40              37             610  2001 Model Year.
----------------------------------------------------------------------------------------------------------------


                                        Table 3--Phase 2 Class II Engine Exhaust Emission Standards by Model Year
                                                                ]grams per kilowatt-hour]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                       Model Year
---------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                              2005  and
                 Engine Class                          Emission requirement             2001          2002          2003          2004          later
--------------------------------------------------------------------------------------------------------------------------------------------------------
II............................................  HC +NOX                                     18.0          16.6          15.0          13.6          12.1
                                                NMHC+NOX                                    16.7          15.3          14.0          12.7          11.3
                                                CO                                         610           610           610           610           610
--------------------------------------------------------------------------------------------------------------------------------------------------------


                       TABLE 4--Phase 2 Handheld Exhaust Emission Standards by Model Year
                                            [grams per kilowatt-hour]
----------------------------------------------------------------------------------------------------------------
                                                                                 Model year
                                                           -----------------------------------------------------
            Engine class              Emission requirement                                                 2007
                                                              2002     2003     2004     2005     2006     and
                                                                                                          later
----------------------------------------------------------------------------------------------------------------
Class III..........................  HC+NOX...............      238      175      113       50       50       50
                                     CO...................      805      805      805      805      805      805
Class IV...........................  HC+NOX...............      196      148       99       50       50       50
                                     CO...................      805      805      805      805      805      805
Class V............................  HC+NOX...............                        143      119       96       72
                                     CO...................                        603      603      603      603
----------------------------------------------------------------------------------------------------------------

    (1) Each engine displacement class has a unique set of exhaust 
emission standards. Boundaries for each class are indicated in 
Sec. 90.116(b).
    (2) Emission standards for classes III, IV, V may be used only if an 
engine meets at least one of the following requirements:
    (i) The engine must be used in a piece of equipment that is carried 
by the operator throughout the performance of its intended function(s);
    (ii) The engine must be used in a piece of equipment that must 
operate multipositionally, such as upside down or sideways, to complete 
its intended function(s);
    (iii) The engine must be used in a piece of equipment for which the 
combined engine and equipment dry weight is under 14 kilograms, no more 
than two wheels are present on the equipment, and at least one of the 
following attributes is also present:
    (A) The operator must alternately provide support or carry the 
equipment throughout the performance of its intended function(s); (B) 
The operator

[[Page 175]]

must provide support or attitudinal control for the equipment throughout 
the performance of its intended function(s); and
    (C) The engine must be used in a generator or pump;
    (iv) The engine must be used to power one-person augers, with a 
combined engine and equipment dry weight under 20 kilograms;
    (v) The engine must be used in a recreational application, with a 
combined total vehicle dry weight under 20 kilograms;
    (vi) Where a piece of equipment otherwise meeting the requirements 
of paragraph (a)(2)(iii) or (a)(2)(iv) of this section exceeds the 
applicable weight limit, emission standards for class III, IV or V, as 
applicable, may still apply if the equipment exceeds the weight limit by 
no more than the extent necessary to allow for the incremental weight of 
a four stroke engine or the incremental weight of a two stroke engine 
having enhanced emission control acceptable to the Administrator. Any 
manufacturer utilizing this provision to exceed the subject weight 
limitations shall maintain and make available to the Administrator upon 
request, documentation to substantiate that the exceedance of either 
weight limitation is a direct result of application of a four stroke or 
enhanced two stroke engine having the same, less or very similar power 
to two stroke engines that could otherwise be used to power the 
equipment and remain within the weight limitations.
    (3) Notwithstanding paragraph (a)(2) of this section, two stroke 
engines used to power lawnmowers or other nonhandheld equipment may meet 
Phase 1 Class III, IV or V standards and requirements, as appropriate, 
through model year 2002 subject to the provisions of Sec. 90.107(e), (f) 
and (h). Such engines shall not be included in any computations of Phase 
2 averaging, banking, or trading credits or eligible production.
    (4) Notwithstanding paragraph (a)(2) of this section, two-stroke 
engines used to power snowthrowers may meet class III, IV, or V 
standards.
    (5) Notwithstanding paragraph (a)(2) of this section, engines used 
exclusively to power products which are used exclusively in wintertime, 
such as snowthrowers and ice augers, at the option of the engine 
manufacturer, need not certify to or comply with standards regulating 
emissions of HC, NOX, HC+NOX or 
NMHC+NOX, as applicable. If the manufacturer exercises the 
option to certify to standards regulating such emissions, such engines 
must meet such standards. If the engine is to be used in any equipment 
or vehicle other than an exclusively wintertime product such as a 
snowthrower or ice auger, it must be certified to the applicable 
standard regulating emissions of HC, NOX, HC+NOX 
or NMHC+NOX as applicable.
    (6) In lieu of certifying to the applicable Phase 2 standards, small 
volume engine manufacturers as defined in this part may, at their 
option, certify their engine families as Phase 1 engines until the 2010 
model year for nonhandheld engine families excluding Class I-A and Class 
I-B engine families, until the 2008 model year for Class III and Class 
IV engine families, and until the 2010 model year for Class V engine 
families. Such engines shall not exceed the applicable Phase 1 standards 
and are excluded from the averaging, banking and trading program and any 
related credit calculations. Beginning with the 2010 model year for 
nonhandheld engine families, the 2008 model year for Class III and Class 
IV engine families, and the 2010 model year for Class V engine families, 
these engines must meet the applicable Phase 2 standards.
    (7) In lieu of certifying to the applicable Phase 2 standards, 
manufacturers of small volume engine families, as defined in this part 
may, at their option, certify their small volume engine families as 
Phase 1 engines until the 2010 model year for nonhandheld engine 
families excluding Class I-A and Class I-B engine families, until the 
2008 model year for Class III and Class IV engine families, and until 
the 2010 model year for Class V engine families. Such engines shall not 
exceed the applicable Phase 1 standards and are excluded from the 
averaging, banking and trading program and any related credit 
calculations. Beginning with the 2010 model year for nonhandheld engine 
families, the 2008 model year for Class

[[Page 176]]

III and Class IV engine families, and the 2010 model year for Class V 
engine families, these engines must meet the applicable Phase 2 
standards.
    (8) Notwithstanding the standards shown in Table 3 of this section, 
the HC+NOX (NMHC+NOX) standard for Phase 2 Class 
II side valve engine families with annual production of 1000 or less 
shall be 24.0 g/kW-hr (22.0 g/kW-hr) for model years 2010 and later. 
Engines produced subject to this provision may not exceed this standard 
and are excluded from the averaging, banking and trading program and any 
related credit calculations.
    (b) Exhaust emissions will be measured using the procedures set 
forth in subpart E of this part.

[60 FR 34598, July 3, 1995, as amended at 61 FR 58300, Nov. 13, 1996; 62 
FR 42643, Aug. 7, 1997; 64 FR 15236, Mar. 30, 1999; 65 FR 24305, Apr. 
25, 2000; 67 FR 68340, Nov. 8, 2002]