LEFT LANE ENDS Sign Requirements

1. When a LEFT LANE ENDS Sign Is Used

Warns that the left travel lane ends ahead and that traffic in the left lane must merge into the adjacent lane where the roadway narrows.

• Left-lane reductions and merging tapers in work zones
• Supplements W20-5 series lane-closure signs where the left lane closes
• Used where the left lane is permanently dropped near work

2. How and Where It Applies

In the field, W4-2L Left Lane Ends is typically positioned at the advance warning area, ahead of the work. Common deployments include left-lane reductions and merging tapers in work zones; supplements W20-5 series lane-closure signs where the left lane closes; used where the left lane is permanently dropped near work. Always confirm its size, retroreflective sheeting, spacing, and placement against the CA MUTCD 2026 and the reviewing agency before finalizing the traffic control plan.

3. Placement and Application Notes

Position W4-2L advance warning area, ahead of the work.

• Place the sign where drivers have a clear, unobstructed view on approach.
• Mount at the standard height and setback from the edge of the traveled way.
• Do not mount with other signs on the same post unless space constraints require it.

4. Standard Sizes and Visibility Considerations

Typical minimum: 48" × 48" on conventional roads; 60" × 60" on expressways and freeways.

• Choose size based on roadway speed, sight distance, and mounting location.
• Maintain high retroreflectivity for maximum night and adverse-weather visibility.

5. California Notes

Used in California lane-closure tapers when the left lane is dropped, reinforcing the merge as the left lane ends and supplementing the word-message lane-closure warnings.

6. Common Field or Planning Mistakes

• Merge direction on the sign does not match the open lane in the field.
• Taper begins before the lane-closure warning is reached.
• Sign spacing not adjusted for the posted speed.
• Wrong size specified for a multilane facility.