Question

CLASS D fire is caused by?
●Solid Substances
●Liquid Substances
● Gaseous Substances
●Chemical Substances​

Answer 1

Answer:

-/Solid Substances

Explanation:

Class D fires involve combustible metals

- /especially alkali metals like lithium and potassium.

-/It also includes metals (Such as -Sodium, Potassium ) that burns when it comes in contact with the room temperature .

Answer 2

Answer:Fire extinguishers contain different chemicals, depending on the application. Handheld extinguishers, which are commonly sold at hardware stores for use in the kitchen or garage, are pressurized with nitrogen or carbon dioxide (CO2) to propel a stream of fire-squelching agent to the fire. The active material may be a powder such as potassium bicarbonate (KHCO3), liquid water, an evaporating fluorocarbon or the propelling agent itself. The most effective and common fluorocarbon used until recently for this application had been bromochlorodifluoromethane (CF2ClBr), referred to as halon 1211. By international agreement, however, production of all types of halons ceased in 1994 because the bromine and chlorine atoms in the chemical were found to migrate over time to the stratosphere, where they react to deplete ozone in a very efficient catalytic cycle.

Many fire extinguishing systems are built into the building or other structure being protected. Water sprinklers are by far the most common type of fixed system because they are inexpensive, highly reliable and safe for people. But water damage cannot always be tolerated (say, in a computer room); it is sometimes ineffective (a fuel storage system); and it is impractical where weight and space are limited (in an airplane). In these situations, fire extinguishers use different materials--ones that flood a protected compartment with a fire-fighting gas. CO2 works well, but is fatal at the concentrations necessary to extinguish a fire, and so cannot be used where people will be present. Bromotrifluoromethane (CF3Br, or halon 1301) is a close cousin to halon 1211, but has a much lower boiling point and toxic level--properties that have made halon 1301 the firefighting chemical of choice for applications where sprinklers cannot be used.

Explanation: