Annals of the M.B.C. - vol. 1° - n° 1 - September 1987


Magliacani G.

Traumatological Centre of Turin - Plastic Surgery Division - Burn Treatment Centre

SUMMARY. Forest fires are not a rare event in Mediterranean countries and they present some peculiar characteristics which affect the types of risk involved, of which the main one is of course burning.The statistically most frequent accidents are lue to sudden flares of flame or by sudden change in the direction of the fire front where fire-fighting teams are at work. In such cases t ic temperature of the heat source reaches maximum levels that may be supposed to be in the region of 500'C; the time of exposure of the fi.-e-fighter is generally 20-30 sec.
We have accordingly designed protective clothing to avert the risk of burns or to limit their effect, taking into account the environmental and climatic conditions in which fires break out ard their characteristic physical features. This type of clothing has the following specifications:
- easy to wear and comfortable even when used for long periods
- protects all the body, and in particular those parts most at risk - face, hands, perineum etc.
- protection time sufficient to allow wearer to pass through fire front at the estimated temperature
- poor accumulator of heat
- allows wearer to feel gradual rise of temperature so that he is aware of imminent danger.

Among the causes of burns to be considered with the utmost attention on account of the incidence and severity of the damages involved, we should certainly include forest fires, a field in which specialist physicians, in collaboration with other technicians, can make significant contributions.
Forest fires, in fact, are a frequent occurrence in the Mediterranean countries, mostly, but not limited to, in the summer season, developing in the bush or amid the trees and undergrowth.
Mediterranean bush fires are characterised by a flame front about 1,5 to 2 metre thick, 2,5 metre high, spreading at a speed of approx. 20/30 cm/sec, and producing an amount of heat per Kg of fuel fully burnt of 3,800 Kcal.
In the case of forest fires preying on tall-trunks, such as Coniferae, the thickness of th,- front is greater (5 to 10 metres), its height is that of tt. c trees involved, but in actual practise combustion above 2,5 m does not lead to a significant temperature increase at ground level. The fires spreads at a lower pace, the energy produced is reduced and the temperature is not as high as in bush fires.
The hazards to be faced by operators engaged in fire quenching operations include, first of all, burns, and secondly traumas which may be produced by the fall of bodies no longer propped up by the vegetation, especially on.slopes, as well as cuts, grazes and other types of wound.
Burns may be due to the fall of incandescent particles, contact with flames suddenly flaring up, an abrupt eh ange in the direction of the flame front produced by wind gusts, a common ~:)ccurrence especially along the sea-coast.
Particularly severe are the bums caused by unsuitable clothes or protective outfits which transfer heat by conduction to the operator's skin they are in contact with while the operator is being overtaken by the fire front.
The exchange of heat through the skin, in fact, takes place much faster, the temperature being the same, when heat is applied by conduction rather than by convection or radiation.
The damages produced by direct contact with the flame are compounded by exposure to the radiant heat that precedes and follows the front.
However, the temperature peak, highest at the centre where it reaches a maximum estimated value of approx. 50WC, generally only lasts a few seconds, by the radiant heat moving with the front, and the time of exposure must be raised by an adjustment coefficient to 30 seconds.
Therefore, the fire front should be viewed as a line moving on and giving rise to an increase in temperature that begins in the form of radiant heat, then continues to increase until it suddenly reaches and maintains for about 10 seconds peak values at centre,. followed by a gradual decrease with further generation of radiant heat at the rear of the front, this process as a whole lasting approx. 30 seconds.
The foregoing information was used to study the characteristics of a protective suit which might suitably ward off the hazards firemen are exposed to when fighting a forest fire.
In order to be effective, the protective equipment should entail a difference between the time it takes the inner wall of the outfit (when exposed to the heat source) to rearch the burn producing temperature (T 1) and the time required to reach the same temperature when no shielding is provided (T).
Having set the protecticri time TP = Tl - T, the higher the TP value, the gre~ ter the protective capacity afforded.
When the values T 1 and T coincide the outfit has no protective value in that it makes no difference whatsoever.
When TP is negative, tte outfit is dangerous and its utilization should be prevented.
For our purposes a sufficient degree of protection is deemend to be provided i -the time difference as a whole exceeds 30 seconds at 300'C will have a TP of only 6 seconds at 500'C.
As we have seen the front has different temperatures over its thickness, hence at all times the TP value must be higher than the time it takes the flame front, with its different temperature values, to overtake a stationary operator, in order to ensure a safety margin is always provided and guarantee effective protection.
To be regarded as safe, an outfit must afford longer protection times in the regions classified as . risk- areas, that is, in the body regions of major aesthetic-functional importance, whose impairment entails difficulties in the administration of treatment and the risk of invalidating effects, such as the face, neck, hands, feet, the perineum and the joints.
An outfit must be comfortable, so that it can be worn throughout the operation. Hence it must not be too heavy, and it must be designed to permit adequate perspiration, sufficient freedorn of movement to the operator's limbs, sensitivity of the hands, these being the indispensable prerequisites for sustained use.
Summer and winter models must be provided, both in compliance with the above-mentioned characteristics.
Moreover, the protective garment must be easy to take off so that it is possible to quickly remove from the operator any residual heat accumulated by the fabric when in contact with the flame.
Protection must be exte ided to the entire body, paying the greatest attention to the "risk" regions, where protective capacity is expected to be highest.
The manufacturing system and the type of materials used must be such that they will guarantee full protection over the entire tirrie of exposure to the fire front and in the event of a sudden flare up.
Hence, the materials used must be fireproofed, which does not amount to no i inflammable materials, but ones burning with a latency time before heat is transferred to the skin, with no residual combustion and dripping.
Fabric suitability must ah.o be ensured by adequate strength against the typical stresses of forest areas which might cause ripping arid tear.
Further characteristics include the lack of pockets or loose parts that might be caught in the vegetation and damage the garment, as well as the elimination of any projecting part which might easily catch fire.
The metal parts, if present, must never come in contact with the flame and with the skin, since this might in turn give origin to burns.
Double seams must be provided, with the outer seam protecting the inner one, so as to prevent the flame from producing an opening in the fabric and exposing a portion of the body to the heat.
Finally, we believe that a protective device conceived in this manner must enable the operator to perceive the gradual increase in temperature and become aware of impending danger so that he can move away from the heat source.
A further warranty of safety for the users is the stability of these characteristics over time.
The outfit produced in keeping with the foregoing provisions (PROMEPACK - PROMETEO) is composed of helmet, cap, hood, overalls, shirt and gloves. It allows for three different protection factors, according to the different functional importance and vulnerability of the body regions.
With the aim of assessing the garment's effectiveness laboratory tests were performed by exposing the suit's walls to heat flows of 200, 300, 400 and 500'C - that is the temperature values of the fire front - and measuring the heat increments directly on the inner wall of the protective outfit.
During these tests, comparative measurements were also performed on clothes manufatured by traditional methods (outfits A and B).
The results obtained are listed in a table, stating the TP in seconds for the specimens examined.

  Factor 1 Factor 2 Factor 3 Outfit A Outfit B






Since a suit's heat insulation value cannot be regarded as absolute, that is, sufficiently high to ensure full protection at all times and under any circumstances, the operators should be informed of the protection limits of the outfit.
A protective device perfectly suited to cope with a specific situation may lose its effectiveness when the thresholds determined at the design stage are exceded.
This entails the need of adequate training programmes with detailed instructions on the suit's proper utilization, i.e. learning under which conditions it will provide maximum protection and being able to perceive approaching danger, so as to avoid the phase in which protection becomes precarious.
In conclusion, effective protection, in this field too as in many other cases, must necessarily be the result of a twofold process whose basic steps are: the careful design and construction of the protective equipment vis-A-vis the hazards to be faced and systematic operator training.
In this particular instance, we believe that the outfit being considered can afford adequate protection, even in the most difficult situations, to the people in charge of fire fighting operations, shielding the different regions of the body in relation to their importance.

RÉSUMÉ. L'incendie de forêt accident non rare dans les pays méditerranéens, présente des caractéristiques particulières qui conditionnent les types de risque qui sont liès, dont le principal est naturellement la brûlure. Les accidents les plus fréquents, selon les staÂstiques, sont causés par des feux imprévus ou par le changement brutal du front de l'incendie
aux abords duquel opèrent les équipes de se(ours. La température de la source de chaleur en de tels cas atteint des valeurs maximales que l'on peut estimer à 500 degrés et le temps d'action du secouriste est en général de 20 à 30 secondes. On a donc étudié un vêtement de protection a~)te à prévenir les risques de brûlures ou a en réduire les gravités, en tenant compte des conditions du milieu et du climat où l'incendie se propage et des facteurs physiques qui le caractérisent. Les qualités spécifiques que l'on demande à ce type de vêtement sont les suivantes:
- facile à endosser et commode pendant tout le temps que le secouriste le porte
- il doit protéger toutes les parties du corps (~t en particulier celles les plus exposées, le visage, les mains, le périnée, etc.
- protéger pendant suffisamment longtemps pour garantir le passage du front du feu aux températures évaluées
- qu'il ne permette pas l'accumulation de chaleur
- qu'il enregistre graduellement l'augmentaticn thermique de façon à prévenir le secouriste du danger imminent.


Contact Us