Notes:
1 - Fire occurs in the vapor/gaseous state.
2 - Fahrenheit 451 refers to the FLASH POINT TEMPERATURE of paper. - When it is hot enough to release enough fuel gases for a fire to start. (Book/movie about censorship – book burning.)
3 - Flammable Range (Lean/Rich) – when there is an appropriate fuel/air mixture for combustion I.e. not too lean (too little fuel), not too rich (too much fuel)
4 - Ignition sources – Static electrical spark, match, pilot light, welding (any spark producing activity), etc.