LOCAL APPLICATION SYSTEMS
Local application systems are used to
protect hazards, such as oil-filled transformers
and paint dip tanks. Ventilating fans,
conveyors, flammable liquid pumps and mixers
associated with the operation may be
interlocked to shut down automatically when
the protection system is activated.
A typical arrangement of a local
application carbon dioxide system is shown in
HALOGENATED GAS SYSTEMS
Several types of halogenated gas systems
have been developed for fire protection
purposes: Halon 104, Halon 1001, Halon
1011, Halon 1202, Halon 1211, Halon 1301,
and Halon 2402. The numbers relate to the
chemical formulas of the gases. The first digit
identifies the number of carbon atoms in the
chemical molecule; the second digit identifies
the number of fluorine atoms; the third digit
identifies the number of chlorine atoms; the
fourth digit identifies the number of bromine
atoms; and a fifth digit, if any, identifies the
number of iodine atoms present. Primarily,
Halon 1301 and Halon 1211 are in general use
in the United States today. These two types are
recognized by the National Fire Protection
Association (NFPA). Standards for their
installation and use are published in the
National Fire Codes.
Halogenated gas systems are used in the
l A clean extinguishing agent is needed.
l Energized electrical or electronic circuits
are to be protected.
Figure 8-34.Local application carbon dioxide system installation.