BS 1125:1987

Foreword
Committees responsible
Specification
Section one. General
1 Scope
2 Definitions
3 Marking
Section two. Materials and design
4 General requirements
5 Requirements for particular materials
6 Soft solder
7 Hard solder
8 Flushing apparatus
9 Volume of discharge per flush
10 Rate of discharge
11 Water line
12 Spill-over level
13 Warning pipes
14 Float operated valves
15 Covers
Section three. Construction
16 Shell
17 Operating lever and pull
18 Flush pipe connection
19 Bottom connection cisterns
Section four. Flush pipes
20 General requirements
21 Special requirements for flush pipes for use with
    cisterns at high level
22 Special requirements for flush pipes for use with
    cisterns at low level
Appendices
A Distortion and dead load tests
B Front thrust test
C Impact test
D Volume of discharge test
E Rate of discharge test for full flush
F Options: Information to be supplied by the purchaser
Figures
1 Flush pipes
2 Front thrust test apparatus
3 Test flush pipe for low level cistern

Cisterns with valveless siphons, nominally 9 litres, for high level, low level and close coupled positions, in both ceramic and plastics.

BS 1125 specifies requirements for WC flushing cisterns with valveless siphons, nominally 9 L (litres), for high level, low level and close coupled positions, together with the necessary flush pipes.

The cisterns specified are of the type which flushes 9 L only, (i.e. the single flush type), or of the type which flushes, as selected, either 4.5 L or 9 L, (i.e. the dual flush type).

Float operated valves and methods of fixing are not covered by BS 1125.

NOTE 1 Dual flush type cisterns are intended for use with washdown pans in domestic premises only.

NOTE 2 The titles of the publications referred to in this standard are listed on the inside back cover.