BS 3251:1976

Foreword
Co-operating organizations
Specification
Section one. General
1 Scope
2 References
3 Definition
4 Marking
Section two. Design
5 Dimensions
6 Character sizes
7 Presentation of information
8 Colour
Section three. Materials and manufacture
9 Choice of materials
10 Characters
11 Removable characters
12 Finish
13 Protective painting
Section four. Tests
14 Overall requirement
15 Numbers to be tested
16 Impact resistance test
17 Colour stability and resistance to weathering
18 Flexibility
19 Security of removable characters
20 Test certificate
Appendix
A Recommendations for fixing indicator plates
Figures
1 Single class A hydrant indicator plate
2 Single class B hydrant indicator plate
3 Double class A hydrant indicator plate
4 Double class B hydrant indicator plate
5 Class C emergency water supply indicator plate
6 Class D meter bypass indicator plate
7 Removable digit and spacer piece

Dimensions for sheet steel, cast iron, aluminium alloy or plastics indicator plates. Colours and finish, tests for impact resistance, colour stability, resistance to weathering, flexibility and security of removable numerals. Recommendations for fixing.

This British Standard specifies requirements for hydrant, emergency water supply and meter bypass indicator plates made from sheet steel, cast iron, aluminium alloy or plastics materials, together with all removable characters and spacer pieces supplied with them.

Four types of plate are specified.

1. Class A plates: hydrant indicator plates for general use except on roads of motorway standard.
2. Class B plates: hydrant indicator plates for use on roads of motorway standard.
3. Class C plates: indicator plates for emergency water supplies, “EWS??.
4. Class D plates: indicator plates for meter bypass valves.