The heat exposure zone is the space around the combustion zone , in which the temperature as a result of heat exchange reaches values that cause a damaging effect on surrounding objects and is dangerous to humans.
By definition, the distance at which the temperature of the air and combustion products reaches more than 60-80 ° C enters the heat-affected zone. Air exchange during a fire is more active than during a quiet time. Cold and hot air is mixed with products of combustion. This process makes him move. As already mentioned above, the products of combustion, along with the hot air rise up, giving way to denser, cold air. Which, in turn, getting into the fire, inflates it even more. When a fire occurs inside a building, an important factor in its intensity is the space over which the fire spreads. Here the important things are the location of the openings in the walls, interior floors (including the materials from which they are made). The height of the room also plays an important role, as well as the composition and quantity of potentially burning objects in this room.
Understanding which way the fire will spread is not so difficult, the main thing is to determine the direction of the airways caused by the fire. Hot air can spread sparks , which, in turn, form a new source of ignition, for example, in the smoke zone . Since the products of incomplete combustion remain, they are the causes of gas explosions (during interaction with oxygen).
See also
- Fire
- Fire safety
- Firefighting