Section 1054.103 - What exhaust emission standards must my handheld engines meet?(a)Emission standards. Exhaust emissions from your handheld engines may not exceed the emission standards in Table 1 to this section. Measure emissions using the applicable steady-state test procedures described in subpart F of this part. Table 1 to § 1054.103 -Phase 3 Emission Standards for Handheld Engines (g/kW-hr)
| Engine displacement class | HC + NOX | CO |
| Class III | 50 | 805 |
| Class IV | 50 | 805 |
| Class V | 72 | 603 |
(b)Averaging, banking, and trading. You may generate or use emission credits under the averaging, banking, and trading (ABT) program for HC + NOX emissions as described in subpart H of this part. You may not generate or use emission credits for CO emissions. To generate or use emission credits, you must specify a family emission limit for each engine family you include in the ABT program. These family emission limits serve as the emission standards for the engine family with respect to all required testing instead of the standards specified in this section. An engine family meets emission standards even if its family emission limit is higher than the standard, as long as you show that the whole averaging set of applicable engine families meets the emission standards using emission credits and the engines within the family meet the family emission limit. The following FEL caps are the maximum values you may specify for family emission limits:(1) 336 g/kW-hr for Class III engines.(2) 275 g/kW-hr for Class IV engines.(3) 186 g/kW-hr for Class V engines.(c)Fuel types. The exhaust emission standards in this section apply for engines using the fuel type on which the engines in the emission family are designed to operate. You must meet the numerical emission standards for hydrocarbon in this section based on the following types of hydrocarbon emissions for engines powered by the following fuels: (1) Alcohol-fueled engines: THCE emissions.(2) Natural gas-fueled engines: NMHC emissions.(3) Other engines: THC emissions.(d)Useful life. Your engines must meet the exhaust emission standards in paragraph (a) of this section over their full useful life as described in § 1054.107 .(e)Applicability for testing. The emission standards in this subpart apply to all testing, including certification, production-line, and in-use testing.73 FR 59259, Oct. 8, 2008, as amended at 86 FR 34517, June 29, 2021