W1-11 HAIRPIN CURVE Requirements
Application notes for W1-11 HAIRPIN CURVE. The official manual distinguishes mandatory standards, recommended guidance, and optional applications; consult the linked sources for the provisions that apply.
California Application & Variants
May be used for a change in alignment of 135 degrees or more. Match the direction; California recommends a large-arrow sign or chevrons on the outside of the curve when this sign is installed. The displayed official face is the left-oriented example; select the orientation that matches the site.
1. When HAIRPIN CURVE Is Used
Warns of a sharp hairpin curve ahead.
- Roadway geometry and approach-warning review
2. Placement and Application Notes
Position W1-11 in advance of the condition, with placement determined from the approach speed, sight distance, and applicable California manual provisions..
- 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: 30" × 30"; 36" × 36"; 48" × 48". 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 W1-11 and its orientation to the actual roadway condition.
- May be used for a change in alignment of 135 degrees or more. Match the direction; California recommends a large-arrow sign or chevrons on the outside of the curve when this sign is installed. The displayed official face is the left-oriented example; select the orientation that matches the site.
- Select size and installation using the applicable California table and responsible agency requirements.
Related Resources
Browse All Sign Series
Verify W1-11 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.
Need to Rent or Purchase This Sign? Contact Public Ready.
Public Ready supports sign selection, project-ready sign packages, and equipment sourcing through qualified providers — with expert support built for compliance.