Inergen
Encyclopedia
INERGEN is a blend of inert atmospheric gases that contains 52% nitrogen
, 40% argon
, 8% carbon dioxide
, used for fire suppression system agent. 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 35-50% to lower the concentration of oxygen to a point that cannot support combustion, but still safe for humans.
Inergen has replaced the use of CO2 in fixed firefighting applications due to the dangers associated with lack of oxygen following activation of a CO2 system. The name is a portmanteau of the name of the lead engineer
on the project, Dr Innes R. Geneson.
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 2% 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 offset the weight of the carbon dioxide, which allows the Inergen blend to have the same density as normal atmosphere. This eliminates the need for special considerations to prevent agent leakage.
Nitrogen
Nitrogen is a chemical element that has the symbol N, atomic number of 7 and atomic mass 14.00674 u. Elemental nitrogen is a colorless, odorless, tasteless, and mostly inert diatomic gas at standard conditions, constituting 78.08% by volume of Earth's atmosphere...
, 40% argon
Argon
Argon is a chemical element represented by the symbol Ar. Argon has atomic number 18 and is the third element in group 18 of the periodic table . Argon is the third most common gas in the Earth's atmosphere, at 0.93%, making it more common than carbon dioxide...
, 8% carbon dioxide
Carbon dioxide
Carbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...
, used for fire suppression system agent. It is considered a clean agent for use in gaseous fire suppression
Gaseous fire suppression
Gaseous fire suppression is a term to describe the use of inert gases and chemical agents to extinguish a fire. Also called Clean Agent Fire Suppression. These Agents are governed by the NFPA Standard for Clean Agent Fire Extinguishing Systems - NFPA 2001 in the USA, with different standards and...
applications. Inergen does not contain halocarbons, and has no ozone depletion
Ozone depletion
Ozone depletion describes two distinct but related phenomena observed since the late 1970s: a steady decline of about 4% per decade in the total volume of ozone in Earth's stratosphere , and a much larger springtime decrease in stratospheric ozone over Earth's polar regions. The latter phenomenon...
potential. It is non-toxic. Inergen is used at design concentrations of 35-50% to lower the concentration of oxygen to a point that cannot support combustion, but still safe for humans.
Inergen has replaced the use of CO2 in fixed firefighting applications due to the dangers associated with lack of oxygen following activation of a CO2 system. The name is a portmanteau of the name of the lead engineer
Engineer
An engineer is a professional practitioner of engineering, concerned with applying scientific knowledge, mathematics and ingenuity to develop solutions for technical problems. Engineers design materials, structures, machines and systems while considering the limitations imposed by practicality,...
on the project, Dr Innes R. Geneson.
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 2% 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 offset the weight of the carbon dioxide, which allows the Inergen blend to have the same density as normal atmosphere. This eliminates the need for special considerations to prevent agent leakage.
Advantages
- Inergen contains no halocarbons. It has no ozone depletionOzone depletionOzone depletion describes two distinct but related phenomena observed since the late 1970s: a steady decline of about 4% per decade in the total volume of ozone in Earth's stratosphere , and a much larger springtime decrease in stratospheric ozone over Earth's polar regions. The latter phenomenon...
potential, and unlike halocarbon agents, it will not produce toxic or corrosive decomposition. - Inergen is safer than carbon dioxideCarbon dioxideCarbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...
in applications where evacuation may not be possible prior to the application of the agent. Inergen systems reduce oxygen concentration only enough to suppress combustion while stimulating breathing efficiency to a disproportional advantage (although human evacuation is clearly recommended). - Inergen is non-toxic, and does not threaten the health, as halocarbon agents do. In some concentrations, halocarbon agents palpitate the heart.
- Inergen has almost the same density as normal atmosphere. No special considerations are needed to prevent agent leakage.
- Because Inergen creates no 'fog' during discharge, escape routes remain visible.
Disadvantages
- Unlike carbon dioxide or halocarbon agents, Inergen agent does not liquify under pressure. Hence Inergen requires more space for storage tanks.
External sources
- Ansul Corporation
- Data Sheet (last retrieved 9 July 2009)