Previous Page Table of Contents Next Page

Fighting fires in Mediterranean forests

Spain, France and Italy face unique difficulties in fighting forest fires. Each country is trying to modernize its own system of fire control and suppression. At the same time, new efforts at regional cooperation are beginning to have results.

Giancarlo Calabri

GIANCARLO CALABRI is Chief of the Forest Fire Service, Ministry of Agriculture and Forestry, Rome.

Fire is the greatest calamity affecting forest management in three Mediterranean countries: Spain, France and Italy. On average, about 20000 fires sweep a total area of 160000 ha of woodland every year in these countries, causing severe losses. Of course, the severity of these fires varies from year to year, depending on the seasons, but the long and dry summers typical of the Mediterranean climate, with high temperatures, low relative humidity and heavy winds, especially in steep areas, provide ideal conditions for dangerous fires to break out. Although the summer is the peak fire season in most areas, another peak season occurs in winter and at the beginning of spring in high mountains and in colder regions, when a layer of small branches, dead leaves and dry grass covers the soil, providing highly combustible material.

A few fires are due to natural causes, notably lightning, but most are man-caused. Negligence is a frequent factor, and yet in many cases malicious intentions bear the main responsibility. The situation has worsened in recent years because of the development of industry and tourism, the rise in living standards and, above all, the urbanization of the rural population formerly exploiting the woods.

Thus, unexploited forests, neither thinned nor cleared, have become more and more exposed to fire because of the heavy accumulation of potential fuel. The increase in the number of tourists, campers and town-dwellers, unaware of environmental problems, is a direct cause of many fires. Furthermore, the absence of a rural population interested in forest conservation, familiar with ground conditions and skilled in the use of implements, has made quick local fire-fighting action either difficult or impossible.

Each of these countries has in recent years taken special measures for protection against fires in the field of both prevention and suppression. In Spain, ICONA (Instituto para la Conservación de la Naturaleza) was given the task of preventing and suppressing fires by a law passed in 1971. Spanish government policy follows three main lines of action: reduction of fuel by means of clearing and opening fuel breaks, education and propaganda campaigns and the creation of an efficient extinction system. The latter is based on a detection network covering all forested areas, a method to deter mine the degree of risk, a network of forest-tracks and water points with depots of pumping engines in each province, fire brigades (cuadrillas retén) equipped with various tools and several aircraft operating over the entire country. The suppression system and the educational campaigns have been considerably developed.

The work on fuel reduction is less advanced; most woods belonging to private estates have been practically abandoned. The suppression activities have succeeded in reducing losses: the total area affected by fire is growing less rapidly than the actual number of fires, indicating that fires, on average, are being stopped earlier. However, the arson problem is on the increase, and many difficulties are arising. New political and technical measures have been proposed to control fuel for fire-hazard reduction and to promote the interest and participation of the population in forest conservation.

In France, the forested areas most exposed to fire (the "red zone") belong to the Mediterranean regions: Provence, Alpes, Côte d'Azur, Languedoc - Roussillon and Corsica. The law of 12 July 1966 prescribes a whole series of measures to protect and reconstitute such areas. In 1971, a special State programme was promoted to finance such measures and to coordinate the activities of the Ministries of Agriculture, the Interior and the National Meteorological Service. An interministerial mission was set up in 1972 for the protection and management of natural Mediterranean areas.

The main task of fire-fighting belongs to the Civil Protection Service, which is part of the Ministry of the Interior, and consists of fire brigades (sapeurs-pompiers) professional firemen and voluntary workers. They have the cooperation of agricultural personnel, professional staff belonging to the Ministry of Agriculture, "sapeurs forestiers" and forest workers and of the Army, Corps of Soldiers, Civilian Safety units and other personnel. The major aircraft belong to the Ministry of the Interior, but some regions hire light aeroplanes during the peak fire seasons.

A CROWDED MEDITERRANEAN CAMPING SITE summer is the peak season for forest fires

French policy until recently was based on forest equipment (network of roads, fuel-breaks and water points), on surveillance and rapid fire detection, on the equipment and training of the sapeurs-pompiers and on public information and propaganda. However, after the heavy fires of 1979, new measures were adopted: the creation of agricultural and pastoral land to interrupt the continuity of forested areas; brush clearing with the same aim, even without landowners' initiatives; and full responsibility granted to local communities, with the technical and financial support of the State.

In Italy, the first regional law for forest protection against fire was promulgated in Lombardy in 1972, and was soon followed by other regional laws. The national law of 1 March 1975 subsequently organized both State and regional activities. Each region was given the responsibility of preparing general plans, including all measures to prevent and to control fire and to restore damaged areas. According to the rate of fire danger, forests were classified into four risk categories, taking into account fire statistics, type of climate and vegetation, and economic and social conditions. The task of detection and control of small fires now rests with the local authorities - town councils, forest guards and police stations. The suppression of larger forest fires is normally organized by a forest authority.

SPAIN'S "EL CONEJO" increasing public awareness of fire prevention

A special forest-fire service with mechanized brigades of forest guards and light helicopters was established by the Ministry of Agriculture. The service works with the cooperation of firemen from the Ministry of the Interior (responsible for all events that threaten buildings or people), of workers trained and equipped by each region and of volunteers or locally organized people. In the most serious cases, even the armed forces are called in. The Air Force operates with air-tankers, the Army with helicopters and light aeroplanes. Other light aeroplanes and helicopters are hired by individual regions themselves.

A BULLDOZER FOR OPENING FIRE-BREAKS a traditional fire-control method being used less and less

The main responsibility for forest protection against fire belongs to the regions, but their plans are lagging because of lack of finances and the consequent lack of technical preparation. The State has the control and management of fire-fighting by aerial means, as well as the organization and training of the State Forest Corps. The fire-suppression sector is, at present, much more developed than the fire-prevention one. A better coordination is needed in this field between State and regional policies and operations.

The fire triangle

The chemical process of fire requires three essential elements - fuel, heat and oxygen - which constitute the sides of the so-called "fire triangle". To extinguish a fire, it is enough to remove one of these elements: fuel, by constructing a fire line; heat, by applying water; oxygen, by smothering with dirt or extinguishing with water. Such actions can be carried out by the use of simple hand tools as well as by highly sophisticated equipment.

Of course, the trend is toward mechanization and more powerful means, but the use of hand tools is still needed in some cases - for instance, to mop up or suppress fires in areas inaccessible to mechanized equipment. Furthermore, hand tools require little training and are often the only suitable tools for occasional workers or volunteers.

In the Mediterranean countries, the usual hand tools are the shovel, the axe, the half-axe and half-grub-hoe, the common rake and the fire rake (a rake with triangular blades), the pruning-hook and, last but not least, the swatter or flip-flap. Ordinarily, the swatter is made from strips of old hoses or foil or, less frequently, from a rubber - vulcanized belting stock. This tool has replaced such old makeshift tools as the oak boughs. Its use requires some skill because hard and inappropriate swatting tends to spread the fire as well as to tire the operator. Various types of universal tools with a single metal shaft and different implements to assemble have been tried out, but the results were unsatisfactory both practically and economically.

Another simple hand tool is the common backpack pump, consisting of a 15- to 20-litre tank of galvanized steel or plastic material, equipped with a slide-action hand-operated pump, made of brass or plastic, having single or double action. The pump nozzle is adjustable for coarse spray or a long-distance straight stream. It is hard and tiring work to operate.

Individual mechanical equipment includes the chain-saw and the brush cutter, to remove fuel, and the backpack pump operated by a gasoline motor-pump (3-5 h.p.) with a 12- to 14 litre plastic tank, to spread plain water or chemicals over the fire. The same tool, equipped with a special nozzle, works as a flame-thrower to set counter-fires. Without the tank, the motor - pump blows a strong current of air. Such action has proved to be very useful in brush fires.

As to collective equipment, tractors are often used to open fire-breaks. Most Mediterranean forests have a rough topography; therefore, instead of tractor-ploughs, heavy bulldozers are often used in fire prevention and control. However, their use meets with practical and economic difficulties, and sometimes with landscape problems. At present, aerial means and chemicals seem to have better prospects. On the other hand, traditional fire-breaks, where all the fuel is removed down to the soil, are being abandoned. Their place is taken by fuel-breaks, strips of land where the fuel is only reduced for easier wildfire control.

A VOLUNTARY FIRE BRIGADE grazing is a cost-effective way of maintaining fuel-breaks

Wherever possible, fire is extinguished by water, which is the best "suppressant". It acts in two ways, by removing heat from the burning material and by smothering it. In areas most exposed to fire, the forest equipment includes water-storage facilities --small storage tanks, with a capacity from 20 to 120 m3, made of various materials (some types of even smaller plastic tanks can be assembled and taken apart very quickly); in hilly sites, large-capacity reservoirs can be made by excavation or by earth or concrete dams.

Among the various types of pumps used, portable centrifugal or positive displacement pumps are very useful, especially with relay tanks and long hose-lays in otherwise inaccessible areas. Centrifugal pumps with trailers and tankers are very common. Light tankers have a capacity from 300 to 800 litres, medium-weight tankers from 1000 to 2000 litres and the heaviest tankers up to 6500 litres. Light tankers are always all-terrain vehicles, i.e. jeeps. The Italian models are equipped with a modular system composed of two units: a tank (400 litres) and a portable pump, easily separated for individual use. Trailers have proved to be less practical on steep and winding roads. The most common tanker model is an all-terrain truck (122 h.p.) with a tank capacity of 3000-3300 litres; the centrifugal pump, combining normal and high pressure, has an output of 1600-1700 litres per minute at 8 bar and 200-250 litres per minute at 40 bar.

Light and resistant hoses are needed to make handling easier and in order to resist high pressure. The diameter of these hoses varies from 23 to 45 mm; it is important to have couplings that are quick and easy to handle. Adjustable nozzles (6-18 mm) give a straight stream, a spray or a fog, by combining nozzle openings and pressures.

Ordinary tankers are restricted to normal roads but can be useful as water-supply points for all terrain vehicles and even for helicopters, especially in dry regions.

Fire-fighters must have adequate clothing and equipment for their personal safety. While fighting fire, they should all wear plastic helmets, long sleeved and fire-resistant shirts or jackets and trousers, as well as boots. Protective goggles and masks are useful sometimes in heavy smoke. Protective gloves are also recommended, except when using hand tools which require a greater hand sensitivity. In Italy the forest-fire service wear white helmets and red overalls in order to be seen clearly, especially in combined operations with aircraft. Other safety items necessary are torches for night work, first-aid and snake-bite kits and food rations.

An efficient and reliable communication system is the most important key to success in reporting fires, planning strategies, reporting on fire behaviour and ensuring safety. A radio network with fixed frequencies reserved for the fire service is needed, together with mobile and light-weight portable radios. Normally a very high frequency/frequency modulation system (VHF/FM) is employed. Often the rough topography requires telecommand high relay points.

Above all, it is essential to have an efficient organization on the ground - with only one fire chief in control at one time - and fire-fighters who are in good physical condition and are properly trained and experienced.

AN ITALIAN FIRE-FIGHTER IN TRAINING adequate clothing and equipment are essential for his safety

The role of aircraft

In recent years aircraft have played an important part in forest-fire protection in the Mediterranean countries. The severity of forest fires and the inaccessibility of many forested areas make their use essential from a technical point of view. Furthermore, aircraft have deeply influenced people and politics from the very beginning, by appearing to be the most effective, rapid and modern method of fire control, even beyond strict economic reasons. At present, various types of aeroplanes and helicopters are operating in the field of prevention, detection and suppression.

Their task in fire prevention, which is normally entrusted to light aeroplanes equipped with loudspeakers or towing advertising posters, consists in warning people of fire risk during high-hazard periods. This is done in several Italian regions. Other fire - prevention measures, such as spraying chemicals to build or maintain fire - breaks, are at present not so frequent.

The main uses of aircraft lie in detection and suppression. Detection is again normally entrusted to light aeroplanes, preferably two-seater (pilot and observer). Their operation is often combined with a ground look-out tower system. Some types of aircraft are equipped with tanks and can drop small quantities of water or chemicals for a first attack against the outbreak of fire. In France, various agricultural aeroplanes carry out the so-called guet armé (armed watch) with loads from 1000 to 2000 litres.

Such aircraft make "direct attacks", by dropping water and chemicals directly on the fire, and cooling hot spots. Larger fires often require "indirect attacks", i.e. temporary retardant lines are built in advance of the fire.

These operations are usually carried out by major aircraft according to the techniques of "water bombing" and "fire bombing". The first consists in dropping fresh or sea water, and is effective for large fires, on condition that the water is dropped in large enough quantities and frequently enough for each drop to be made before the effect of the previous drop has dissipated and the fire has reignited. Fire bombing consists of dropping long-term chemical retardants, having a lasting effect against the fire advance, and allowing a considerably lower frequency of drops. This technique is, of course, mainly suitable for indirect attacks.

Regarding major air-tankers, the European countries at the beginning chose the water-bombing technique, using amphibious aircraft. The Canadair CL-215 can collect water without stopping. The water is scooped into 5500-litre tanks while the plane skims along a lake or the sea, and is later released over the fire. This method is very effective when there are short distances between the source of water and the fire, especially in flat regions. Large fires, however, require at least two planes at a distance of 20 km, and four planes for distances exceeding 40 km.

The fire-bombing technique is restricted to purely land-based operations because of the large proportion of chemical in the mix (10 percent or more). However, the time spent in getting to and from the airport is often counterbalanced by the effectiveness of less frequent drops, and by the speed of the planes which is generally higher than that of the CL-215.

Spain and France bought 25 CL-215, in the early 1970s. In 1979, however, France experimented with fire bombing, using a Douglas DC-6, carrying a load of 12000 litres of retardant and releasing it by gravity.

In Italy, experimentation started in 1978 with a Modular Airborne Fire Fighting System (MAFFS) built in the USA. This consists of five modular tanks and twin exhaust manifolds, containing a total of about 12000 litres. The tanks are pressurized, enabling the retardant to be discharged at different pressures, so that the drop is rather like a spray from an aerosol can. The spray allows a better coating of the forest fuel and little impact at ground level, which adds to the safety of fire-fighters and property. The system is put in and taken out of a Lockheed c-130 military aeroplane in less than two hours without requiring any aircraft modification.

REFILLING A CANADAIR CL-215 FOR "WATER BOMBING" water is the safest fire "suppressant"

Light helicopters have largely been used in Italy so far, equipped with small containers to drop water and chemicals for initial attacks. The containers are normally buckets of varying capacities, having an open top and being sling-mounted to the helicopters, and are refueled while hovering over a water source or, sometimes, by a fire truck after landing. Italy recently bought two Canadair CL-215 which are kept on standby at Pisa for deployment.

Despite their expense, helicopters give satisfactory results in suppressing fires, because of the accuracy of drops. Moreover, they can be used flexibly, especially in mountainous and inaccessible areas. "Helitack" consists of disembarking a crew and tools at the site of the fire to attack it immediately. Besides the transport of men and tools, helicopters can remove injured personnel; bring in fuel, parts and food; and act as flying headquarters to guide air and ground operations. The following models of helicopters have mostly been used: Lama SA 315 (Aérospatiale), Agusta Bell 205 and 206, Breda Nardi NH 500-D, with containers of 300- to 1000-litre capacity.

The aerial means in operation all over the major Mediterranean countries are as follows. In Spain, in 1979, 14 Canadair CL-215, from the air bases at Torrejón de Ardoz, Santiago de Compostela, Manises, Palma de Mallorca, Reus and Jerez de la Frontera flew about 4000 hours against fires. Ten minor aeroplanes, having capacities of 1000-1500 litres, flew about 1035 hours. The Canadairs, bought by the Forest Service, are operated by the Air Force.

In France, in 1980, the Civil Protection Service of the Ministry of the Interior had three Douglas DC-6 and 12 Canadair CL-215. Eight agricultural aeroplanes (two Grumman AGT CAT: capacity 1200 litres; three Dromader PZL: 1700 litres; two Pilatus: 1000 litres; and one Trush Commander: 1200 litres) were also hired by various regions and flew about 560 hours. Two reconnaissance aeroplanes (Piper Navaho and Cessna Centurion) and six helicopters belonging to the State gave their support.

In Italy in the same year about 30 light aeroplanes and helicopters hired by different regions flew almost 8000 hours for fire detection and suppression. The Army operated in Sardinia with four Piper aeroplanes and five AB 205 helicopters; the Air Force operated all over the country with one Lockheed c130 equipped with MAFFS from Pisa airport (in Tuscany) under the direction and at the expense of the Ministry of Agriculture.

In September 1979 the European Parliament proposed a strict cooperation on forest-fire control between France and Italy, especially in the use of aircraft. Some preliminary meetings took place at a technical level. A wider cooperation on the same subject is to be promoted involving other European countries.

A LAMA SA 315 DURING "HELITACK" disembarking men and tools as close to the fire as possible

To sum up, there are good prospects for the development of aircraft to control fire, particularly in the field of suppression. Small aircraft can be used to detect and to fight fires by rapid initial attacks and major aircraft can provide decisive support against larger fires.

However, it must be understood that aircraft alone can never succeed in extinguishing fires. The cooperation of ground forces, firemen and foresters is always needed to resist in fire lines, to mop up burned areas, and prevent useless dangers and expenses. It is more and more important that all fire-fighters should be trained to this end. They should have a sufficient knowledge of aircraft operations and understand and abide by the relative rules and procedures.

Fire-fighting chemicals

Fire-fighting chemicals may be used in two ways - as suppressants, when applied directly to a fire to suppress the flames, or as retardants, when applied ahead of fire to reduce the rate of spread or intensity. Suppressants may be chemicals in liquid, gas or powdered form; retardants are generally liquid. Most retardants act as a suppressant if applied directly to the flame. Frequently, applications on wild fires achieve suppression and retardation simultaneously.

Short-term retardants are water modifying chemicals. Their effectiveness depends on an ability to retain moisture and to keep the fuel wet. Some are wetting agents, reducing the surface tension of water droplets, thereby improving penetration and surface spreading. Others are viscous agents or water thickeners, producing a type of gel with water, modifying the air-drop characteristics and reducing dispersion and evaporation. In this way water has better penetration, clings to the branches and leaves, and is held for a longer time against the fuel. In every case, modified water acts as a cooling agent and its retardant effect]lasts until it is evaporated.

Wetting agents, such as "surfactants" (surface active agents) or detergents are effective in fire situations where penetration is important; "wet water", for instance, can penetrate into wood or charcoal six to eight times better than plain water. They cannot be applied with aerial means because "wet water" tends to be dissipated and lost while dropping, even more so than plain water. On the other hand, viscous agents are effective either when applied with ground pumpers or when dropped from aerial tankers. Gels or thickened water can be built up on forest fuels into a film as much as 20 times thicker than a film of plain water; evaporation loss is thus greatly reduced. Viscous agents are organic algae or inorganic polymers. Certain clays (such as bentonite and, above all, attapulgite) are also used to make gels with water. The concentration of a short-term retardant mixture is normally less than one percent.

Long-term retardants are flame inhibiting chemicals which alter the combustion process by means of chemical reactions. They are salt solutions involving some form of phosphate or sulphate in combination with ammonium, and generally have in addition a thickener (a gum or a clay), a corrosion inhibitor and a dyeing agent, all mixed with water. The water provides little or no contribution to the retardant effect and is primarily a vehicle to carry the chemicals to the forest fuels. Even after the water has dried up, the chemicals have a long - term retardant effect until sufficient rain has fallen to wash them off the fuel. Combustion is reduced by coating and insulating the fuel, thus preventing the escape of volatile gases, and above all by diluting the combustible gases of pyrolysis with noncombustible gases given off by the retardant in the presence of heat. In this way, the burning fuel is smothered and the non-ignited fuel is rendered almost impossible to burn.

Retardant products currently used come in two types: dry powder and liquid concentrate. The proportion of chemical in the mix is normally high (10 percent or more). The various products give gum-like or water-like retardants, which are more or less advantageous depending on the types of forest fuels and on the method of dropping. Such chemicals are nontoxic to man or animals; basically they are agricultural fertilizers with a few additives to inhibit corrosion and spoilage and to colour the liquid. They can cause trouble, like fertilizers, only if used in excess on limited spaces. For instance, a heavy application can have a burning effect on vegetation, cause irritation and chafing on people and sometimes pollute water. Furthermore, these chemicals are several times more expensive than the short-term retardants. Some of them pose difficult mixing problems and are abrasive to pumping equipment. They all require improved logistics for storage, mixing and distribution, and adequate training in presentation and use.

Despite such disadvantages, the use of long-term chemical retardants has become fully established in Mediterranean countries as well as in other regions of the world which have severe fire problems and a shortage of water. Chemicals nowadays, especially when used with aircraft, seem to be the most effective way to cope with fire.

In Spain and France the amphibious Canadair normally use plain water only taken from the sea, lakes or hydroelectric basins. However, recently in France, light aeroplanes have been using short-term retardants (colloids diluted 0.7 percent) and medium - term retardants (ammonium phosphate diluted six percent). A chemical made in France (INIGRAL MT), containing ammonium phosphate in a saturated solution, plus a viscosity improver (a mineral colloid), a corrosion inhibitor, and stabilizing and dyeing additives, was utilized by Douglas DC-6 aeroplanes in 1979 and 1980 with good results. Ground forces have experimented with short-term and long-term retardants on a small scale only.

In Italy, neither short-term retardants, foams nor other suppressants are commonly used, but long-term retardants have been largely adopted for ground and air applications in recent years, notably in Sardinia. The chemicals most used are PHOSCHECK XA (Monsanto) by fixed-wing aircraft, FIRETROL 936 (Chemonics) by helicopters and ground applications and PHOSCHECK 259 by ground-tankers. PHOSCHECK is a powdered concentrate. FIRETROL, a liquid one. The military aircraft Lockheed c-130 dropped an average of 90 tonnes of PHOSCHECK XA (about 700000 litres of mix) yearly in 1978 and 1979. A wider use of PHOSCHECK 259 is made by the State railway system along embankments to prevent fire in dangerous areas. The yearly consumption has reached about 400 tonnes. The negative effect in terms of fire hazard of increasing the growth of brush and grass is counterbalanced by the protection provided by the vegetation against erosion and landslides.

On the whole, the use of long-term retardants has shown no notable disadvantages so far, even in terms of the ecological consequences. The main obstacles to a wider application are the high costs of chemicals and adequate logistics for storage, mixing and distribution.

The role of computers

As a general rule, successful fire control should take into account many different kinds of information. Therefore, electronic computers with high speed, large memory capacities and sophisticated monitoring systems may be advantageous in various phases of planning and organization. First of all, electronic computers are essential to process statistics so as to have full information in a short time. These forest-fire statistics, including the number and causes of fires, areas swept by fire, forest fuels affected, and the people and means employed to extinguish the fires, are indispensable in order to take preventive and suppression measures and to control their results.

The establishment of a fire-danger rating system, based on an adequate knowledge of forested areas, weather forecasting and fire behaviour, is strictly bound to Electronic Data Processing (EDP), as well as any system of fire simulation. It is plain that planning and organization of any measure to control fire should usefully be based on precise calculations, to avoid improvisation and unrealistic influences.

Despite the severity of forest fires, the use of EDP in the Mediterranean countries so far has been restricted to partial initiatives and particularly to fire statistics. On the other hand, the modest extent and economic value of forested areas, mostly in mountainous or hilly sites, the difference between climatic conditions, the presence of various human activities as well as the fact that the fire-control authorities belong to different public bodies, are causing some concern.

In Spain, lCONA uses a computer system for fire statistics. In France, in 1972, the "opération Prométhée" started to study forest fires in the Mediterranean region to improve the knowledge and effectiveness of the fire service. The Centre de traitement de l'information is financed by the Ministries of the Interior, of Agriculture and of Transport and gives regular and special statistical data. A cartographic automatic representation is being promoted. In Valabre, the Centre de coordination zonale des moyens terrestres et aériens makes use of a computer to collect and process data and to decide interventions. In Italy, in addition to fire statistics, the use of computers is restricted to local studies on fire behaviour and fire weather forecasting in Piedmont and the Veneto. No fire-danger rating system has been established so far, not even in limited areas.

Economic and practical reasons tend to increase the use of electronic data processing in every field. There are definite prospects for a development and deployment of modern technology to protect Mediterranean forests against fire in the future.

PRESCRIBED FIRE IN A PINE STAND reducing dangerous fuel

Previous Page Top of Page Next Page