MUTCD W5-2a: NARROW BRIDGE and NARROW UNDERPASS Signs
The W5-2a sign is covered in Section 2C.18 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
- Guidance · Recommended (should)A NARROW BRIDGE (W5-2) sign (see Figure 2C-6 ) should be used in advance of any bridge or culvert having a two-way roadway horizontal clearance of 16 to 18 feet, or any bridge or culvert having a roadway horizontal clearance less than the width of the approach travel lanes. Where these conditions exist for an underpass, a NARROW UNDERPASS (W5-2a) sign (see Figure 2C-6 ) should be used.
- Guidance · Recommended (should)Additional emphasis should be provided by the use of object markers, delineators, and/or pavement markings.
Where to read the rest
- Full text: MUTCD Section 2C.18: NARROW BRIDGE and NARROW UNDERPASS Signs
- Minimum sign sizes by roadway type are in the size section for this chapter: Section 2C.03
- Mounting height, lateral offset and retroreflectivity for any sign: MUTCD sign placement guide
Related signs in Section 2C.18
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.