(a) Divide your product line into families of portable fuel containers that are expected to have similar emission characteristics throughout the useful life.

(b) Group containers in the same emission family if they are the same in all the following aspects:

(1) Type of material (including pigments, plasticizers, UV inhibitors, or other additives that may affect control of emissions).

(2) Production method.

(3) Spout and cap design.

(4) Gasket material and design.

(5) Emission control strategy.

(6) Strategy for venting pressure.

(c) You may subdivide a group of containers that is identical under paragraph (b) of this section into different emission families if you show the expected emission characteristics are different.

(d) You may group containers that are not identical with respect to the things listed in paragraph (b) of this section in the same emission family if you show that their emission characteristics will be similar throughout their useful life.

[72 FR 8533, Feb. 26, 2007, as amended at 80 FR 9089, Feb. 19, 2015]