Foam Concentrates For Fighting Fires
The foam concentrate is a mixture of different raw materials such as solvents, salts, corrosion inhibitors and mainly surfactants.
In case of synthetic products, there are two types of surfactants: hydrocarbon chain, which are primarily responsible of foaming capacity and foam stabilisation, and fluorinated, in which part of the hydrogen chain atoms are replaced by fluorine atoms.
The fluorinated surfactants are the key component in AFFF agents because they bring to foams repellence and resistance to hydrocarbons.
They add also the ability to form an aqueous film of only a few microns on hydrocarbons.
Due to the many changes in regulations, raw materials and fuels, the manufactures of foam concentrates have developed or modified their products to adapt them both legally and operationally to the market demands.
Both the new AFFF agents, whose fluorinated surfactants are mainly C6, and the foams known as Fluorine Free (3F) have been lately the innovations and main lines of development for several manufacturers.
The development of more concentrated products is also a trend in the market, in which products of 1% are very common in the petrochemical industry, far from the traditional 6%.
Currently, there are on the market AFFF and AR-AFFF that can be dosed at 0.5%. The logistic advantages of these type of products in the case of large foam demands are evident with respect to traditional 3% and 6%.
Another trend is the increasing market demand for synthetic-based products (AFFF and AR- AFFF) compared to traditional protein (FP, FFFP and FFFP-AR). The best firefighting performance, better burn back resistance along with no-degradation over time are the key to success.
Fluorine Free Fire Fighting Foams
Fluorine Free Fire Fighting Foams have increased their popularity because of environmental restrictions in some countries.
The foams without fluorinated components have existed for many years in the market (protein, multi expansion foams, Class A forest retardants, etc..) although it is also true that in the last decade synthetic fluorine products have been developed for Fire Fighting Class B, with the goal of being valid alternative to AFFF agents, but with less environmental impact.
Until the appearance of this new generation of products without fluorine, the forceful application of foams was only effective if AFFF products were used.
However, some new Fluorine Free are also able to be used directly on hydrocarbons, although its behaviour and efficiency is still far from AFFF performance, especially when it is used with non-aspirating nozzles.
Despite of the significant progress reached in the development of this product range, still have some limitations and AFFF or FFFP foams are still not ready to be replaced without serious evaluation.
Before replacing an AFFF or FFFP by a Fluorine Free foam, it is necessary to check if the new solution have the same certifications and ratings than the existing product.
It is highly recommended to carry out a comparative fire testing with both products, evaluating the effectiveness of both in different applications, with the available resources in each case (proportioning, nozzles, etc..) and avoiding a simple “paper” comparison based on the documentation of the products.
Although foam concentrates (0.1-1%) have been traditionally used in Class A fires (solids), new developments have also allowed the use of AFFF and AR-AFFF products with at very low dosage rates (0.5%).
In order to use these products with accuracy in the proportioning, it is strongly recommended the use of electronically controlled proportioning systems.
A flowmeter is installed in the water line and this information is sent to a control unit, which controls the foam injection system, accurately adjusting the amount of foam required for each water flow.
These equipment are very common in fire trucks, but can also be used in forest systems, fixed installations, etc.
For more information on the Class A & B Fire Fighting Foam Concentrates we distribute, view the accompanying product brochure from Auxquima.