Inergen

Inergen is a trademarked fire suppression product of Ansul Corporation. Inergen is a blend of inert atmospheric gases that contains 52% nitrogen, 40% argon, 8% carbon dioxide [ref: Ansul Inergen MSDS Form F-9313-7] . It is considered a clean agent for use in gaseous fire suppression applications. Inergen does not contain halocarbons, and has no ozone depletion potential. It is non-toxic. Inergen is used at design concentrations of 40-50% to lower the concentration of oxygen to a point that cannot support combustion.

A component of Inergen is carbon dioxide, which allows the human body to adapt to the environment of reduced oxygen that is present after discharge of agent. Discharge of Inergen results in an approximate 3% concentration of carbon dioxide within the space. This directs the human body to take deeper breaths and to make more efficient use of the available oxygen.

The nitrogen and argon components are used to offset the weight of the carbon dioxide, which allows the Inergen blend to have the same density as normal atmosphere. This is done in order to prevent special considerations from needing to be taken in order to prevent agent leakage.

Advantages

* Inergen does not contain halocarbons. It has no ozone depletion potential and unlike halocarbon agents, does not chemically react with the fire to create acid byproducts.
* Inergen is safer to use than carbon dioxide in applications where evacuation may not be possible prior to discharge of the agent. Inergen is designed to be breathable after discharge for a short period of time (space evacuation is recommended). Pure carbon dioxide is not.
* Inergen is non-toxic, and does not create the same health risks as the use of halocarbon agents. In certain concentrations, halocarbon agents can cause heart palpitations.
* Inergen has the same density as normal atmosphere. No special considerations are needed in order to prevent agent leakage.
* Inergen does not create a 'fog' during discharge so it will not block views of the exit paths.

Disadvantages

* Inergen requires more space for storage tanks. Unlike carbon dioxide or halocarbon agents, Inergen agent does not liquify under pressure.
* Inergen requires that 40-50% of the room atmosphere be replaced with Inergen in a short amount of time. This creates a large amount of pressure, which must be relieved in order to prevent damage to the enclosure.
* Inergen can only be re-filled in the UK by a TYCO company creating lifetime tie in problems. Whilst it is possible that another company can be responsible for the servicing of the system they will have to use a TYCO company to re-fill the cylinders in the event of a dis-charge.

ee also

* Argonite
* FE-13
* FM-200
* Halon 1211
* Halon 1301

External Sources

* [http://www.ansul.com Ansul Corporation]
* [https://www.ansul.com/AnsulGetDoc.asp?FileID=13368 Data Sheet] (last retrieved 4 nov 2007)