Oxygen candles are used as a backup source of breathable air in an emergency. In addition, they supply an on-demand source of oxygen, utilised in aeroplanes, space stations, and other applications such as safe havens and refuge chambers.
A safe supply of oxygen is critical to support life. We are dependent on oxygen for survival; our bodies consume it to produce energy. If primary oxygen sources are scarce, these generators are on standby, ready to produce a finite amount of oxygen via a chemical reaction.
Oxygen is produced from a thermal, chemical reaction. Oxygen candles house a mixture of sodium chlorate, barium peroxide and iron powder; the oxygen-producing chemical is sodium chlorate.
This chemical reaction requires a significant amount of energy input, hence the need for iron powder. Iron powder burns at a higher temperature around 600°C (1112°F); as it heats the iron becomes very hot and breaks down the sodium chlorate. This reaction produces oxygen, sodium chloride (common salt) and iron oxide through a process known as thermal decomposition.
The initial energy required to start the reaction occurs when a specific initiation mechanism, a brass starter, ignites the iron powder.
2Fe +3O2 -> 2Fe2O3
-> Heat
NaClO3 -> 3O2 +NaCl
Oxygen candles produce a lot of heat. Steps must be followed to ensure everyone’s safety, including the use of gloves and a strict no moving policy.
The candle supplied by MineARC Systems burns for approximately 60-90 minutes, producing 2600L of oxygen. This amount can provide approximately 20 hours of breathable air for four people. An oxygen candle cannot have its oxygen production regulated or halted and once ignited; it produces oxygen at a rate of approximately 28 Litres per minute until it is exhausted.