They’ve been around for decades, but will an industry push towards environmentally acceptable alternatives see traditional scheduled extinguishing agents become a thing of the past?
FM-200, NAF-SII, Halon 1301. Generations of fire protection professionals have come to appreciate the effectiveness of these traditional ozone depleting substances (ODS) and synthetic greenhouse gases (SGG), but as their name suggests, they’re not so great for the environment.
ODS damage the Earth’s protective ozone layer, allowing more harmful ultraviolet (UV) radiation from the sun to reach the earth, and SGG contribute to global warming which traps heat in the atmosphere.
Still, these agents are widely used across the industry, despite a number of readily available environmentally acceptable alternatives on the market.
Inert gases, FK-5-1-12 fluid, CO2 fixed fire suppressions, water sprinkler systems, water mist systems, hybrid water mist/inert gas systems, condensed aerosols and oxygen reduction fire prevention (ORFP) systems are all available for a variety of uses, but unlike their predecessors have no ozone-depleting potential and nil or very little global warming potential.
The Fire Protection Industry (ODS & SGG) Board, also known as the FPIB, has been working hard to shed light on the benefits of using these alternatives when designing a new or upgrading an existing fire protection system.
A webinar I hosted in May talked industry members through the benefits and uses of alternatives, and discussed the need for an industry-wide transition.
In the webinar I gave an example; if we took a typical sized system with about 250kg of scheduled extinguishing agent HFC-227ea, that would relate to about 805 metric tonnes of CO2 equivalent.
In terms of greenhouse gas emissions, it would be equivalent to 172 passenger vehicles driven for a year, or in terms of emissions, 4.4 rail cars worth of coal burnt. This is why we talk about transitioning.
FPIB’s discussion couldn’t have come at a better time – Australia’s gradual hydrofluorocarbon (HFC) phase down began on 1 January 2018.
The phase down is part of a government push to convert industry away from the traditional agents through a gradual reduction in the maximum amount of bulk HFCs permitted to be imported into Australia.
The aim is to achieve an 85 per cent reduction in imports of HFCs by 31 December 2035, and a greater industry move towards environmentally acceptable alternatives, as agreed to in the Montreal Protocol.
These alternatives each have their own extinguishing mechanisms, benefits and uses.
Inert gases reduce the oxygen in a risk environment to the point that fire cannot be sustained. In most cases it also prevents oxygen in the room from decreasing to an unsafe level.
FK-5-1-12 fluid, of which Novec 1230 is a common brand name, is a man-made clean agent that can be used in occupied areas. It suppresses the fire by removing the heat and interrupting the combustion process.
CO2 fixed fire suppression systems contain carbon dioxide in liquid form. When released into the area being protected it decreases the percentage of oxygen available for combustion.
Water sprinkler systems are still one of the most useful and cost-effective ways to put out a fire. These systems control the spread of fire to allow egress out of the building and protect the building from the fire growth, and can be used for Class A fires involving combustible materials. They are not suitable for Class B liquid fires.
Water mist systems discharge very fine water droplets. The mist controls, suppresses or extinguishes fires by cooling the flame and surrounding gases by evaporation. Environmentally friendly, these systems are highly effective at extinguishing large flammable liquid fires.
Hybrid water mist systems are a combination of clean agent inert gas and water. The mist is produced by having nitrogen injected into the water stream at the nozzle. This creates extremely small droplets and acts to reduce the oxygen concentration in the protected risk.
Condensed aerosol fire extinguishing agents consist of very fine, usually potassium-based particles suspended in a gas. The particles interfere with and stop the fire chain reaction. While very efficient, condensed aerosols are not classed as clean agents as they leave a residue after discharge.
Oxygen reduction fire prevention (ORFP) systems prevent, rather than supress, fires. These systems use a technology that produces hypoxic air by partly filtering out oxygen from the ambient atmospheric air to below 15 per cent. At this level, common flammable solid materials and liquids cannot ignite.
While the industry should consider these systems, rest assured there is no urgency to do anything.
You do not need to go out and replace systems that you have immediately because of this phase down.
Supply will continue and HFCs already in the country won’t be impacted, however, there are a number of points along the life of the system where alternatives can be considered.
Possible times to switch to an alternative include during a facility upgrade or change, at the time of the 10-yearly pressure testing of cylinders, when there is a change in the fire risk of the protected areas or following a discharge.
However, no change over should be carried out without proper planning and consideration.
Plans should include an analysis of the alternatives to determine which is the best system for the job, taking into account cost, application, space and storage needs, amount of agent required, discharge time and speed and maintenance.
It’s also essential you engage with your service provider to ensure a smooth transition and the safe decommissioning of an existing system.
If you haven’t got a plan and you have a discharge, you’re under a lot of time pressure then to come back and make sure your system or facility is protected.
For more information, go to www.fpib.com.au/media/281663/fpib_alternative_systems_brochure.pdf
About the Author
Daniel Wilson is a Fire Protection Industry (ODS & SGG) Board member.
