Yes, perhaps this would never? or rarely occur, but it shouldn’t be allowed at all.

CABO will recommend that the new FHWA interim approval regarding two-stage bicycle turn boxes when applied in Calif. not allow implementation of a mandatory prohibition for bicyclists to perform standard vehicular-style left turns if motorists are not similarly prohibited. I hope that you would support CABO in this effort.

Prohibiting people bicycling from performing a normal vehicular left turn where vehicle operators are not prohibited from making a left turn is an unacceptable diminution of bicyclists ability to travel effectively. I am not opposing the interim approval for use of bicycle turn boxes, only the provision allowing prohibition of bicycle movements. It seems fairly obvious that it benefits people bicycling better to leave the option as it is, for the person bicycling to choose which method of turning left serves them best at any one time and location.

None of the following provisions of the FHWA MUTCD would be necessary when bicyclists intending to turn left have the option/choice/right to use the bicycle turn boxes or to perform a vehicular-style left turn.

The use of regulatory signing for two-stage bicycle turn boxes is required where use of the boxes by turning bicycles is mandatory. The signs used shall be the Two-Stage Bicycle Turn Box Advance (R9-23) regulatory sign and the TwoStage Bicycle Turn Box (R9-23a, R9-23b) regulatory sign as shown in Attachment IA-20-2. The following design and installation conditions apply to the use of regulatory signing for two-stage bicycle turn boxes.
i. Mandatory use of a two-stage bicycle turn box by turning bicycles should be limited to those locations where physical or operational conditions make it impracticable or unsafe for a bicyclist to merge and make the appropriate turn as would any other vehicle.
ii. Where use of a two-stage bicycle turn box by turning bicycles is mandatory, the Two-Stage Bicycle Turn Box Advance (R9-23) regulatory sign shall be mounted in advance of an intersection. The sign should be placed at an adequate distance in advance of the intersection to discourage bicycle traffic from unnecessarily moving out of the bike lane in preparation for a turning movement.
iii. Where use of a two-stage bicycle turn box by turning bicycles is mandatory, at least one Two-Stage Bicycle Turn Box (R9-23a or R923b) regulatory sign shall be mounted at the intersection.
1. When the R9-23a sign is used, it shall be mounted on the near side of an intersection.
2. When the R9-23b sign is used, it shall be mounted on the far side of an intersection iv. The minimum size of the Two-Stage Bicycle Turn Box regulatory and Advance regulatory signs shall be 12 inches in width by 18 inches in height.