BS 5306-5.2:1984

Foreword
Committees responsible
Code of practice
0 Introduction
1 Scope
2 Definitions
3 Characteristics of Halon 1211
4 Planning
5 Contract arrangements
6 System design
7 System operation
8 Enclosure characteristics
9 System components
10 System design procedure
11 Maintenance
12 Safety
Appendices
A Deep-seated fires
B Examples of calculation of Halon 1211 quantity where
    there is natural ventilation
C Examples of calculation of Halon 1211 quantity where
    there is forced ventilation
D Example of design calculation for balanced system
E Example of design calculation for unbalanced system
Tables
1 Physical properties of Halon 1211
2 Quality of Halon 1211
3 Halon 1211 flame extinguishment concentrations
4 Halon 1211 inerting concentrations
5 Halon 1211 total flooding quantity
6 Pipes
7 Maximum pipework spans
8 Friction loss in screwed pipe fittings and valves
9 Friction loss in welded pipe elbows
10 Safety clearances to enable operation, inspection,
    cleaning, repairs, painting and normal maintenance
    work to be carried out
Figures
1 Isometric diagram of Halon 1211 pressurized to 25
    bar at 21 deg C
2 Isometric diagram of Halon 1211 pressurized to 10.5
    bar at 21 deg C
3 Pressure drop against mass flow rate for Halon 1211
    in galvanized steel pipes
4 Mass flow rate per unit area against nozzle pressure
    with Halon 1211/Nitrogen for nozzle type A
5 Mass flow rate per unit area against nozzle pressure
    with Halon 1211/Nitrogen for nozzle type B
6 Type A nozzle
7 Type B nozzle
8 Example of balanced system
9 Example of Halon 1211 mass flow rate against
    container pressure for balanced system
10 Example of unbalanced system
11 Example of Halon 1211 mass flow rate against
    container pressure for unbalanced system
12 Label to be displayed at manual control
13 Label to be displayed at entrances to hazard
14 Extended mass flow rate of Halon 1211 to maintain
    concentration in enclosures with openings
15 Initial amounts of Halon 1211 to produce a 2.5 %
    (V/V) residual concentration in enclosures equipped
    for mechanical mixing
16 Initial amounts of Halon 1211 to produce a 5 %
    (V/V) residual concentration in enclosures equipped
    for mechanical mixing
17 Initial amounts of Halon 1211 to produce a 7.5 %
    (V/V) residual concentration in enclosures equipped
    for mechanical mixing
18 Time required for interface between effluxing Halon
    1211/air mixtures and influxing air to descend to
    the centre of enclosures not equipped for mixing

Gives recommendations for the design and installation of Halon 1211 total flooding systems on premises.

This Section of this code gives recommendations for the design, installation, maintenance and safety of Halon 1211 total flooding fire extinguishing systems in buildings or plant.

Such a system consists of an installation designed to convey Halon 1211 from storage containers for the protection of particular plant or parts of the premises against possible fire risk. Such systems may be piped or otherwise connected.

This code provides factual data on the characteristics of Halon 1211 and the types of fire for which it is a suitable extinguishant.

The code does not cover the design of explosion suppression systems.

Two methods of operation, viz. manual and automatic, are described Advice is given on the selection of a system and on the operational method; also included are detailed recommendations on the design, maintenance and efficient operation of installations. Reference is also made to the part which Halon 1211 systems should play in general schemes of fire protection of premises, having regard to safety as well as efficiency.

NOTE 1. Unless otherwise stated, all pressures are gauge pressures (in bar) 1 bar = 10⁵ N/m² = 10⁵ Pa.

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