Single File Traffic supplementary plate - Diagram 518
The Single File Traffic plate tells drivers to proceed in single file where a road that normally carries two lanes has been narrowed. It is a face-only supplementary plate for quick-fit frames, fitted beneath a Road Narrows sign (Diagram 517L or 517R): printed on RA1 Class 1 engineering-grade reflective sheeting on a 3mm plastic backing, conforming to Chapter 8 and The Red Book, and made in the UK.
Key features
-
Diagram 518 - the standard Single File Traffic supplementary plate.
-
Pairs with Road Narrows faces - fits beneath Diagram 517L or 517R in the same set-out.
-
Chapter 8 compliant - conforms to Chapter 8 of the Traffic Signs Manual and The Red Book.
-
RA1 Class 1 reflective - engineering grade for lower-speed roads.
-
725 x 275mm on a 3mm plastic backing.
-
300mm hole centres - suits mini quick-fit frames.
-
Non-metallic - no scrap value.
-
Made in the UK.
Where it is used
- Beneath Road Narrows warning faces on street works
- Single-file running past roadworks, plant and obstructions
- Urban, residential and other lower-speed roads
- Utility, civils and construction works
- Event routes and site access
Pairing and set-out
Diagram 518 is a supplementary plate, so it does not stand alone - fit it below a Road Narrows Left or Right face (Diagram 517) so drivers know why they are merging. Refer to current government guidance for placement and spacing.
Fixing and compatibility
This listing is the printed face only - quick-fit frames are sold separately. The plate is drilled on 300mm hole centres to suit mini quick-fit frames; check the toggle centres on your existing frames before ordering.
Specification
| Specification |
Detail |
| Diagram reference |
518 (Single File Traffic) |
| Length |
725mm |
| Height |
275mm |
| Depth |
3mm |
| Backing |
3mm plastic board |
| Reflective grade |
RA1 Class 1 (engineering grade) |
| Hole centres |
300mm |
| Compliance |
Chapter 8, The Red Book |
| Origin |
Made in the UK |
Customisation
Faces can be printed to your specification in GRP, composite, aluminium or plastic, with 300mm, 450mm, 750mm or 900mm hole centres. Email sales@streetsolutionsuk.com for custom plates or ask about trade-account pricing.