An innovative new fire-suppression system will help protect airports and combat environmental fallout from firefighting foams.
Health and environmental concerns linked with firefighting foams have put airport operators on notice.
Issues at Sydney Airport, the Army Aviation Centre at Oakey in Queensland and Brisbane Airport, among others, have resulted in the latter introducing a new environmental protection policy. The move comes as airports around the world face pressure over the use of foams containing the compounds perfluorooctane aulphate (PFOs) and perfluorooctanoic acid (PFOAs). The compounds have been used internationally for decades to fight fires.
Under the Brisbane Airport policy, hangars will be approved only if their design prevents the release into the environment of any pollutants spilled inside that facility. At the heart of the problem many airports are facing are the shortcomings of aqueous film forming foam (AFFF) deluge systems and oscillating foam monitors. They have come under criticism for their lack of speed in extinguishing hangar fires, the high volume of water they use and excessive discharges of foam that have caused damage to aircraft and harm to the environment.
Environmental focus
To address such issues, Brisbane Airport is using a limited release fire-suppression system that meets the requirements of the Environmental Protection Authority. Delta Fire installed the new system in a new 2500 square metre aviation hangar at Brisbane Airport. Believed to be the first of its kind in Australia, it complies with the Australian Building Code. It was installed before a highly publicised incident last year in which thousands of litres of toxic foam leaked into the river from another hangar at Brisbane Airport, contaminating the environment and sparking a public warning for people not to eat locally caught seafood.
The Delta Fire installation is an automated foam deluge system that uses high expansion concentrate; in essence, this means it is triggered by triple infrared flame detectors and uses a special concentrate that is discharged via 36 generators.
Among its advantages is that it does not need an electrical supply and nor does it require external air for foam production – the system creates foam from smoke gases, smoke-contaminated air and hot air. This leads to a rapid drop in temperature in a hangar as the hot air is cooled in the generators, where it is aspirated and sprayed with water from the generator nozzles. Smoke emissions are reduced and fire ventilation is unnecessary.
Significantly, the solution requires less than 1000 litres of concentrate to operate the system for 15 minutes, delivering about 2000 cubic metres a minute of the foam. This is just 1% of the water that would be used by a comparable foam monitor installation.
To address leakage concerns, the hangar floor slopes towards a drain at the hangar door. Any liquids are collected in this drain and are contained in an underground tank beneath the fire pump house for licensed disposal off-site. This tank has more than enough capacity to contain foam discharge and any other drained liquids.
Watch this space
Results from the Brisbane Airport hangar project involving Delta Fire will undoubtedly help inform a global response from airports whereby PFOs and PFOAs are likely to be completely eliminated from firefighting efforts at such crucial public sites.
The risks facing airports that get it wrong environmentally with firefighting foams are very real. To manage such dangers, they will need assistance from a reputable fire-protection service with the experience, products and services to meet the most rigorous of standards.
With public safety on the line, there is no room for error.
Delta Fire specialises in the fire protection of high-risk, high-hazard environments such as airports and industrial sites. Visitwww.deltafire.com.au for more details.