Guidance document for subfleet averaging and reporting for on-road motorcycles: chapter 4


4. Family Emission Limits and Subfleet Averaging Requirements

4.1 What is a family emission limit?

As outlined in section 32.1 of the Regulations, a family emission limit (FEL) refers to “the maximum emission level established by a company for an engine family for the purpose of emissions averaging”.

Using this approach, a company may use emissions averaging as the basis for demonstrating compliance with the Regulations by certifying some motorcycles to specified FELs above the applicable emission standard and other motorcycles to FELs below the standard, provided that the calculated sales-weighted average emissions level of such motorcycles does not exceed the applicable emission standard.

4.2 Family emission limits are used for the purpose of averaging exhaust and fuel tank permeation emissions of a company's new motorcycle subfleet of a given model year. What are the subfleets?

Pursuant to section 32.1, each of the following groupings of motorcycles constitutes a subfleet for the purpose of emissions averaging:

  1. all Class I and Class II motorcycles certified to a family emission limit (FEL) in respect of the optional HC+NOx exhaust emission standard
  2. all Class III motorcycles certified to an FEL in respect of the applicable HC+NOx exhaust emission standard
  3. all motorcycles with a non-metal fuel tank certified to an FEL in respect of the fuel tank permeation emission standard

4.3 Family emission limits are established by a company. Are there restrictions as to how high the family emission limits can be?

Yes. As specified in subsection 32.2(2) of the Regulations, which references section 449 of the U.S. Code of Federal Regulations, the maximum allowable family emission limits (FELs) for HC+NOx emissions for Class III motorcycles are established at 5.0 g/km for the 2006--2009 model years and 2.5 g/km for the 2010 and later model years. Similarly, the maximum allowable FEL for HC+NOx emissions for Class I and Class II motorcycles of the 2006 and later model year is 5.0 g/km. There are no maximum FELs for fuel tank permeation emissions.

4.4 How does a company conform to subfleet averaging requirements?

For the purpose of the subfleet averaging requirements of the Regulations, a company's subfleet of motorcycles that are certified to family emission limits can effectively be divided into two main groups as depicted in Figure 1.


Figure 1: Illustration of the division of a company's given subfleet of
motorcycles certified to FELs.

Image of Figure 1

For most companies subject to the subfleet averaging requirements, the vast majority of their motorcycles available in Canada have equivalent motorcycles (i.e., same engine family) sold concurrently in the U.S. which meet the following criteria (represented by Group A in Figure 1):

  • each motorcycle of the subfleet is covered by a U.S. Environmental Protection Agency (EPA) certificate
  • each motorcycle conforms to the FEL referred to in the certificate
  • each motorcycle belongs to an engine family of which the total number of units sold in Canada does not exceed the total number of units sold in the United States

Paragraph 32.2(3)(a) of the Regulations allows a company's subfleet to include motorcycles that conform to an FEL that is greater than the applicable HC+NOx emission standard, but lower than the maximum allowable values, or the fuel tank permeation emission standard in the group of motorcycles that are sold concurrently in Canada and in the U.S., provided each motorcycle within the subfleet meets the criteria for Group A.

The above provision is included in the Regulations on the basis that the U.S.EPA requirements serve as an anchor towards ensuring that any variation in the environmental performance of this group of motorcycles relative to the average standards would be small.

Group B consists of motorcycles that do not meet the criteria for inclusion in Group A. Accordingly, Group B would consist of motorcycles that are not sold concurrently in Canada and in the U.S. (i.e., “Canada-unique” models with no U.S. equivalent), and motorcycles that are sold concurrently in Canada and in the U.S that belong to an engine family of which the total number of units sold in Canada exceeds the total number of units sold in the United States.

Paragraph 32.2(3)(b) of the Regulations allows a company's subfleet to include one or more motorcycles that conform to a family emission limit that is greater than the applicable HC+NOx emission standard, but lower than the maximum allowable values, or the fuel tank permeation emission standard, but that do not meet all of the criteria for inclusion in Group A. However, the average HC+NOx value or the average fuel tank permeation value, as the case may be, must not exceed the applicable emission standards in respect of

  1. the entire subfleet; or
  2. only those motorcycles in Group B.

4.5 How does a company demonstrate compliance with subfleet averaging requirements?

A company demonstrates compliance with the subfleet averaging requirements by submitting an end of model year report that conforms to the requirements outlined in Chapter 7 of this document and by complying with all applicable standards.

4.6 Can selected motorcycles that meet the criteria for Group A be included in Group B for the calculation of the average emission values?

No. The calculation of the average emission values for Group B, as required under paragraph 32.2(3)(b) of the Regulations, must include only motorcycles that do not meet the requirements of Group A as defined in the previous question.

This requirement is established to remove the opportunity for companies to artificially lower the average emission value for Group B.

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