Which of the following suppresses combustion by disrupting a chemical reaction, by doing so it kills the fire?

A.
Halon

B.
CO2

C.
water

D.
soda acid

Explanation:
Halon is a gas that was widely used in the past to suppress fires because it interferes with the chemical
combustion of the elements within a fire. It mixes quickly with the air and does not cause harm to computer
systems and other data processing devices. It was used mainly in data centers and server rooms.
It was discovered that halon has chemicals (chlorofluorocarbons) that deplete the ozone and that
concentrations greater than 10 percent are dangerous to people. Halon used on extremely hot fires degrades
into toxic chemicals, which is even more dangerous to humans.
Halon has not been manufactured since January 1, 1992, by international agreement. The Montreal Protocol
banned halon in 1987, and countries were given until 1992 to comply with these directives. The most effective
replacement for halon is FM-200, which is similar to halon but does not damage the ozone.
Incorrect Answers:
B: CO2 suppresses fire by starving it of oxygen, not by disrupting a chemical reaction. Therefore, this answer is
incorrect.
C: Water suppresses fire by lowering the temperature of the fuel to below its ignition point or by dispersing the
fuel, not by disrupting a chemical reaction. Therefore, this answer is incorrect.D: Soda acid fire extinguishers are CO2-based fire extinguishers. The soda and the acid react to produce CO2.
CO2 suppresses fire by starving it of oxygen, not by disrupting a chemical reaction. Therefore, this answer is
incorrect.

Harris, Shon, All In One CISSP Exam Guide, 6th Edition, McGraw-Hill, 2013, p. 473