Abstract
For valuable assets and critical applications, fire suppression might not be enough. Damages caused by an incipient stage fire, secondary damages due to the activation of the fire suppression system itself or downtime of critical assets could cause unacceptable losses. In these cases, fire can be prevented by using hypoxic air (HA) rather than suppressed. HA technology for fire prevention, also known as oxygen reduction system, is based on a continuous reduction of the oxygen in the protected enclosure in order to limit the availability of oxygen to the combustion process: typically a small fraction of the oxygen in the air is replaced with nitrogen. The effect of low oxygen concentrations on the combustion process was investigated by a literature survey of existing pertinent sources. However, most of the tests found in the literature were not performed in a way which is adequately representative of the conditions created by HA systems. Because of this lack in the state of the art, it was therefore decided to develop an ad hoc ignition propensity test method able to assess different configurations. The performance of HA was then explored by carrying ignition propensity test on materials which can be found commonly in applications which lend themselves for HA technology. The tests were also carried out to study the performance of HA beyond the design parameters set by international standards.
Abbreviations
- HAT:
-
Hypoxic air technology
- HA:
-
Hypoxic air
- O2 :
-
Oxygen
- N2 :
-
Nitrogen
- MOC:
-
Minimum oxygen concentration (vol%)
- LFL:
-
Lower flammable limit (vol%)
- C st :
-
Stoichiometric oxygen/fuel concentration (vol%)
- m oxygen :
-
Oxygen concentration (vol%)
- t ign :
-
Ignition time (s)
- PVC:
-
Polyvinylchloride
- PMMA:
-
Polymethylmethacrylate
- FR:
-
PUR rigid foam polyurethane
- P oxygen :
-
Oxygen partial pressure (atm.)
- T:
-
Temperature (K)
- E:
-
Activation energy (kJ mol−1)
- R:
-
Universal gas constant (J K−1 mol−1)
- AIT:
-
Auto ignition time (s)
- MIE:
-
Minimum ignition energy (J)
- MLR:
-
Mass loss rate (g s−1 cm−2)
- V:
-
Flame spread velocity (m s−1)
- FET:
-
Flame exposure time (s)
- PET:
-
Post exposure time (s)
- PP:
-
Polypropylene
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Acknowledgments
The author is grateful to Mr Geir Jensen for specifying research tasks and his valuable comments on the paper.
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Chiti, S. A Pilot Study on Hypoxic Air Performance in Fire Prevention. Fire Technol 51, 393–407 (2015). https://doi.org/10.1007/s10694-014-0393-6
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DOI: https://doi.org/10.1007/s10694-014-0393-6