Division 2.2.2 Provision shall be made to prevent excess evaporative emissions and fuel spillage caused by a missing fuel filler cap. This may be achieved by using one of the following:

an automatically opening and closing, non-removable fuel filler cap,

design features which avoid excess evaporative emissions in the case of a missing fuel filler cap,

any other provision which has the same effect. Examples may include, but are not limited to, a tethered filler cap, a chained filler cap or one utilizing the same locking key for the filler cap as for the vehicle’s ignition. In this case the key shall be removable from the filler cap only in the locked condition.