W20-8 SLOW (STOP/SLOW PADDLE) Requirements
Application notes for W20-8 SLOW (STOP/SLOW PADDLE). The official manual distinguishes mandatory standards, recommended guidance, and optional applications; consult the linked sources for the provisions that apply.
California Application & Variants
Caltrans publishes a California-modified W20-8 STOP/SLOW paddle drawing with a 24 × 24-inch face. The federal designation remains W20-8; a separate (CA) code is not assigned. The existing federal 18-inch layout is retained below, while the California drawing is provided separately. Use the applicable flagger-control requirements to select the paddle size.
California STOP/SLOW paddle — 24 × 24 inches
Caltrans modification dated July 19, 2021. The sheet shows both STOP and SLOW faces. These are overall face dimensions.
1. When SLOW (STOP/SLOW PADDLE) Is Used
The SLOW face of a flagger's STOP/SLOW paddle tells approaching traffic to proceed slowly when directed by the flagger. The linked drawing also shows the separate R1-1 STOP face on the reverse side.
2. Placement and Application Notes
Position W20-8 in the flagger’s hand as a STOP/SLOW paddle, per CA MUTCD Chapter 6D.
- Place the sign where the intended road users have a clear, unobstructed view on approach.
- Use the mounting height and lateral placement specified for the sign and installation type.
- Use sign assemblies and supplemental plaques only as provided in the applicable manual and approved design.
3. Layout Sizes and Visibility Considerations
Linked-layout dimensions: 18" × 18". Check the applicable MUTCD and agency requirements for the required installation size.
- Choose size based on roadway speed, sight distance, and mounting location.
- Use the visibility and material requirements specified for this sign and installation.
4. Sign Selection Checks
- Match W20-8 and its displayed legend to the intended condition.
- Check the source drawing for the required directional or message variant.
Related Resources
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Verify W20-8 Requirements
This is an educational reference. Verify sign use, size, placement, and application against the current CA MUTCD, Caltrans sign specifications, Standard Plans, and the reviewing agency. Official source links are gathered in one place.
View official sourcesEducational reference only. This is not an official Caltrans, FHWA, or local agency publication and is not legal or engineering advice. Always verify sign selection, size, placement, spacing, and application against the current CA MUTCD 2026, Caltrans sign specifications, Standard Plans, project documents, and the reviewing agency’s requirements. Local jurisdictions may impose additional requirements, and final selection, placement, and dimensions may require engineering judgment or agency approval. Reference editions: California MUTCD 2026 (effective January 18, 2026) and the Federal MUTCD 11th Edition with Revision 1.
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