MUTCD R2-4P: Minimum Speed Limit Plaque and Combined Maximum and Minimum Speed Limits Sign

The R2-4P sign is covered in Section 2B.24 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

• Standard · Required (shall)
  A Minimum Speed Limit (R2-4P) plaque (see Figure 2B-3 ) shall be displayed only in combination with a Speed Limit sign. Where used, the R2-4P plaque shall be mounted below a Speed Limit (R2-1) sign.
• Option · Permitted (may)
  Where engineering judgment determines that slow speeds on a highway might impede the normal and reasonable movement of traffic, the Minimum Speed Limit (R2-4P) plaque may be installed below a Speed Limit (R2-1) sign to indicate the minimum legal speed. In lieu of a sign assembly with the R2-1 sign and R2-4P plaque, the Combined Maximum and Minimum Speed Limits (R2-4a) sign may be used.

Where to read the rest

• Full text: MUTCD Section 2B.24: Minimum Speed Limit Plaque and Combined Maximum and Minimum Speed Limits Sign
• Minimum sign sizes by roadway type are in the size section for this chapter: Section 2B.03
• Mounting height, lateral offset and retroreflectivity for any sign: MUTCD sign placement guide

Related signs in Section 2B.24