Flammable liquids
Water solubility
Ability to mix with water Often affects fire extinguishment "Alcohol" foam Hydrocarbons don't mix Polar solvents do mix
Hydrocarbons
Compounds composed of only carbon and hydrogen Ex: gasoline, kerosene, diesel fuel, solvents and heavy lubricating oils.
Pyrophoric liquid
A liquid that will ignite spontaneously in air at or below 130 *F.
Flammable liquid
A liquid with a flashpoint below 100*F and vapor pressure below 40 psi at 100* F Vapors can readily ignite. Example: gasoline
Polar solvents
Liquid fuels which are water soluble or water miscible Ex: alcohols, ketones acetone, amines, and anhydrides
Combustible liquids
Liquids with a flashpoint equal to or above 100* F Ex: fuel oil
Flashpoint
Minimum temp to which a liquid must be heated to produce enough vapor to allow a vapor flash to occur when an ignition source is present.
Ignition Temperature
Minimum temp to which a material must be heated to cause the material to ignite. ( no spark or open flame needed)
Fire point
Temperature at which a liquid gives off sufficient vapors to sustain combustion.
Boiling point
Temperature at which vapor pressure equals atmospheric pressure Liquid rapidly becomes a vapor
Flammable range (explosive range)
The concentration of fuel vapor and air needed to form an ignitable mixture. Expressed in % vapor/ air. Ex: gasoline UEL: too rich (7.6%) LEL: Too lean (1.4%) So anything between 1.4-7.6 is flammable
Vapor pressure
The pressure resulting from the evaporation (vaporization) of a liquid. - vapor pressure increases with temperature - vapor can push through a foam blanket Ex: gasoline= 2-3 psi
Vapor density
VD of air=1 VD below air rises VD above air sinks
Specific gravity
Weight of a liquid compared to water SG of water: 1 SG less than 1 floats SG more than 1 sinks