MUTCD R15-4: Light Rail Transit Only Lane Signs
The R15-4 sign is covered in Section 8B.12 of the Manual on Uniform Traffic Control Devices, 11th Edition. Below are the provisions from that section that describe when the sign is used and how it is placed.
What it means and when it is used
- Option · Permitted (may)Light Rail Transit Only Lane signs may be used on a roadway lane limited to only LRT use to indicate the restricted use of a lane in semi-exclusive and mixed alignments.
- Guidance · Recommended (should)If used, the R15-4a, R15-4b, and R15-4c signs should be installed on posts adjacent to the roadway containing the LRT tracks or overhead above the LRT only lane.
Placement and mounting
- Option · Permitted (may)If the trackway is paved, preferential lane markings (see Chapter 3E) may be installed, but only in combination with Light Rail Transit Only Lane signs.
Where to read the rest
- Full text: MUTCD Section 8B.12: Light Rail Transit Only Lane Signs
- Mounting height, lateral offset and retroreflectivity for any sign: MUTCD sign placement guide
Source: Manual on Uniform Traffic Control Devices, 11th Edition (Federal Highway Administration, December 2023, public domain). Excerpts are shortened and shown out of context; read the full section before specifying a sign. Your state may still be operating under the 2009 edition or a state supplement. Official manual: mutcd.fhwa.dot.gov.