STCW Basic Training Exam #1 Latest Questions With Passed Solutions!!

What are the conditions needed for a fire to occur? - Answer-fuel (material that acts as a fuel) sources of ignition (chemical, biological, or physical) oxygen What are the components of the fire tetrahedron? - Answer-heat, fuel, oxygen, chain reaction How do you stop a fire? - Answer-Remove any of the components of the fire tetrahedron (i.e. remove fuel, oxygen, heat, or interrupt the chemical reaction) Oxygen - Answer--21% ambient air -robust flaming combustion down to 15-16% -surface combustion (smoldering) down to about 11% -loss of consciousness in atmospheres with 12% or less oxygen Heat - Answer-anything that produces the required temperature for ignition -sun -open flame -chemical reaction -sparks -friction Fuel - Answer--only vapors burn -liquids and solids must first be vaporized -tendency of a substance to vaporize is an indication of its ability to burn -liquids vaporize more readily than solids Chain reaction - Answer--you can have oxygen, heat, and fuel in the same place and still not have a fire-fuel and oxygen relationship must be balanced (i.e. in the flammable range) -heat must be sufficient to bring fuel to its ignition What is a flash point (of a liquid)? - Answer--the lower temp that a liquid can give off sufficient gas to form a flammable gas mixture near the surface of a liquid -lowest temp at which we can have fire -fire flashes across surface given sufficient oxygen and an external source of ignition What is a Fire point? - Answer--just above the flash point, liquid gives off flammable vapors rapidly enough to support continuous combustion What is ignition temperature? - Answer--substance starts to burn -heat from external heat source -auto-ignitio, no external source of ignition needed What is auto ignition? - Answer-vapor generated ignites without any outside ignition source What is vaporization? - Answer-rate increases with temperature What is spontaneous combustion? - Answer-heat is generated by a chemical action within a substance and this continues until you have ignition (usually begins with oxidation and combines oxygen and gives off energy in the form of heat) What is lower flammable limit? - Answer-the least concentration of flammable vapors in air that will burn What is upper flammable limit - Answer-the greatest concentration of flammable vapors in the air that will burn What are the results of combustion? - Answer-smoke, flame, heat, and gases_____________ is the result of incomplete combustion - Answer-smoke White or light grey indicates ____________ burning - Answer-free