Industrial Fire Journal - Fire & Rescue - Hemming Group Ltd
No escaping the trends
Published:  11 April, 2008

Bio fuels have already had a big impact on our everyday lives – even Virgin Atlantic has tested bio fuels in a 747 short haul flight – which means firefighters must be prepared for the added problems of extinguishing bio fuel fires. Luc Jacobs, Product & Environmental Manager, Arctic Fire Fighting Foams, showcases some results of recent foam tests on E95.

What makes bio fuels a special problem when it comes to firefighting is the addition of ethanol. The problem for firefighters is that ethanol is a polar solvent and so only alcohol resistant foams can be considered.

Think about a world where all vehicles on the roads are using bio fuels. Fire brigades will need to replace their existing foam stocks to alcohol-resistant type foams, and review the quantities required to extinguish even the smallest fires.

Alcohol or polar solvent fires in general require indirect or gentle application of firefighting foams, and as they are typically stored in smaller tanks protected by foam chambers or other fixed systems, Type II or indirect application is straightforward.
However, in the case where the fixed system is damaged or becomes inoperable, monitor application is necessary, and the operator must ensure that the foam stream hits a back wall (or other object) to create the gentle flow of foam onto the product surface.

Today, due to the demand for bio fuels, ethanol is stored in larger tanks making it almost impossible to hit the tank wall to disperse the foam, the only application method is directly onto the fuel’s surface. But plunging foam into ethanol will destroy most AR foams.

What is needed is a definitive test to determine what effect the different types of application and varying application rates would have on ethanol.
Tests in the USA have concluded that only AR/AFFF’s are suitable for such fires – but they have never tested Solberg RF 3x6 ATC.

To collect relevant data, Solberg Scandinavian AS undertook a comprehensive testing regime using various test pans (EN1568, LASTFIRE etc) using different water types (tap and sea) but always using E95 as a fuel.

Tests were carried out, strictly adhering to laid down test protocols but also including high application rates and extended application times to establish best practice when applying foam to ethanol. Foams used were Solberg RF 3x6 ATC, Arctic Foam 600 (3x6) ATC and Arctic Foam 603 EF (3x3) ATC.

The results were recorded and a sample of them is shown below.
Following on from the tests carried out using the EN1568 protocol, further test were completed using the LASTFIRE test protocol for hydrocarbons but substituting heptane for E95. Of course it was not possible to use a water layer, as ethanol is miscible with water but all the other criteria (pre-burn time, application rate, application time, torch test and burn back resistance) were all strictly adhered to. One of these tests, using the system nozzle, had successfully extinguished an ethanol fire using the LASTFIRE test protocol for hydrocarbons.

In conclusion, Solberg Scandinavian can offer its customers a full set of data that will demonstrate how effective Solberg RF3x6ATC is at extinguishing bio fuels – whether they be E10 and/or up to E95 blends.

Caption: EN-1568/4  fire tests on E95 fuel (October 16, 2007) – comparison between  Arctic AR-AFFF and RF 3x6 ATC.
 In the design of Solberg RF 3x6 ATC, ethanol performance was one of the key parameters due to the emergence of biofuels. RF 3X6 ATC contains no fluorosurfactants or organohalogens.