Sophisticated foam technology solutions can stop blazes in their tracks, but the input of fire-safety experts is crucial in the setup phase.
Fires at petrochemical sites are often frightening in their scale and potential for destruction.
The presence of gas and petroleum tanks at such facilities adds an especially volatile element to the danger, while the environmental fallout from such blazes can be significant. A reminder of the possible fallout came in March 2019 courtesy of a large fire at a Houston-area petrochemicals terminal in the United States which burned for days, sending a plume of toxic smoke 1200m into the air, with the fire spreading to seven storage tanks holding gasoline components.
The key with such fires is to douse or contain them as quickly and efficiently as possible. Encouragingly, an extensive array of firefighting foam concentrates can counter petrochemical fire risks. Foam deluge systems are commonly used to safeguard gas and petroleum tanks, while provision of quality extinguishers and hoses that distribute foam is also part of the safety mix.
The foam systems mix a foam concentrate at specific proportions with water to, in essence, create a foam blanket that smothers the fire and cuts off its oxygen supply.
Seek professional advice
While foam may seem like a relatively simple fire-suppression tool, it is part of a sophisticated system and requires intelligent use.
The best fixed and mobile high-volume foam delivery systems are required when fighting hazardous chemical fires. Two broad categories of foam are typically used – aqueous film-forming foams (AFFFs), FluoroProtein (FP) etc, which contain fluorinated surfactants; and fluorine-free foams. Both foams should pass performance and characteristic testing to ensure they are compatible with system designs for firefighting equipment.
Expert advice is required to choose the most appropriate type of foam for the relevant fire given that some foams may now be subject to strict management and containment requirements due to the risk of toxin compounds such as perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) impacting the environment. Highly publicised issues at airports around Australia have put the spotlight on the use of PFOAs and PFOs, leading to the introduction of new environmental protection policies in some jurisdictions.
Bans on foams may have significant consequences for high-hazard facilities because they have traditionally relied on AFFFs, which contain PFOs or PFOAs. They have long been considered to be more effective than fluorine-free alternatives, so any decision should be made in consultation with fire-suppression specialists.
How it is delivered
Firefighting foam is typically applied in two ways – non-aspirated, through water nozzles, sprinklers or deluge nozzles; and aspirated, through foam-making devices such as branch pipes, top pourers, foam cannons, foam sprinklers or high-expansion generators.
Again, getting advice on the best combination of solutions is critical, while an ongoing maintenance program is also important. Such fire-suppression systems must be able to withstand a hostile and highly corrosive environment while also being easy to maintain.
There is no doubt that foam concentrates can put out fires faster and with lower product volumes than similar agents, which can substantially lessen property damage on petrochemical sites.
However, it takes considerable expertise and experience to design an effective foam-suppression system. Given the high stakes for petrochemical sites as they seek to protect their people and commercial assets, there is no room for complacency or amateurs.
Delta Fire specialises in the fire protection of high-risk, high-hazard environments such as petrochemical and industrial sites. Visit www.deltafire.com.au for more details.