This blog contains following topics study
- Fire definition
- Fire Pyramid ( Fire Triangle + One morden concept element)
- Fire extinguishing
- Stages of Fire & Dire detectors
- Reasons of fire
Fire definition
Fire is a rapid redox reaction which is accompanied by Heat, Smoke and flame.
Fire Pyramid
Four elements are necessary to iginite fire and continue it.
1. Fuel
2. Oxygen or Oxydiser
3. Heat or Source of fire
4. Chain reaction in fire which continues fire.
Incomplete Fire produces carbon monoxide which is toxic and creates invisibility.
Fire extinguishing
Fire can be stopped
1. Stop or remove fuel.
2. Remove oxygen below 14 ~ 18% by adding inert gas like CO2 or Nitrogen
3. Remove heat faster than libration.
4. Break chain reaction by removing free redicals in fire. For this Dry chemical powder or Halogenated Hydrocarbons are used. (Hydrogenated Hydrocarbons are banned in some countries)
Stages of Fire & Dire detectors
1. Incipient stage :
Ionization takes place in this phase. Ionization fire detector can detect this fire.
2. Smoldering stage:
Smoke generation this this step. Photoelectric fire sensor can detect this stage of fire
3. Flame stage:
Flame start in this step smoke is reducing and heat is increasing. Infrared sensor can sense this stage.
4. Heat stage:
Heat, flame, smoke, and gases are generated in this phase.
Reasons of fire
Study of 25000 reported cases from 1968 to 1977 by Government of India
