INTUMESCENT PRODUCTS AND FIRE PROTECTION SYSTEMS

Introduction to fire prevention
 

Fires and blazes
1. Early propagation and sparks
2. Flash over
3. Blaze
4. Cooling down and extinguishing
Fire hazard assessment
Conclusions

 
Fires and blazes :

A blaze is defined as a reaction to combustion which occurs in a violent and uncontrollable way. More precisely, we can use the word blaze in the case of undesired combustion, uncontrollable by man, that takes place in locations not originally designed for these purposes and that involves combustible materials not originally intended for this purpose, caused by the addition of a sudden burst of energy.

In our modern industrial society, combustible materials are in abundance and consequentially, possible sources of sparks are many.

Fire is fed only when there is an adequate quantity of comburent, generally the oxygen contained in the air, and continues until its concentration dips below 14% (this figure vary with the type of combustible material).
Some materials and substances contain a sufficient quantity of oxygen in their molecular make up to burn without an external source of oxygen. The most well-known of these are explosive substances and cellulose.

When fire and flames (the latter considered the principal vehicle of propagation) develop due to either accidental or malicious reasons, a blaze could be ensue: there are four phases that characterise a blaze, defined by temperature and time factors.

The increase in temperature is very slow and almost linear, due to the small quantities of combustible material involved and the great heat dispersion in the still cold environment.

The temperature increases and grows exponentially. Generally, the FLASH OVER phase results temperatures that rise until reaching 500/600 °C over a period of time that can vary from 5 to 25 minutes, depending on the type of combustible material and especially on the quantity of comburent available.

The FLASH OVER phase is considered the point of transition between the combustion and flame phases to the blaze phase.

3.  Blaze :

In this phase, all the flammable material becomes involved in the combustion and the temperature begins to soar, fed by the significant quantity of heat produced. The dispersion into the environment is now limited while the transmission of heat through the walls and ceilings begins to gain greater importance, caused by the enormous difference in temperature between the dividers and the external environment.
The duration of this phase depends essentially on the quantity of combustible material present and especially on the quantity of comburent.

Generally, a total blaze is characterised by temperatures that exceed 900°C, at times reaching 1100°C, and the increase in temperature remains constant until a theoretical equilibrium is achieved between the room involved in the blaze and the external environment.

The blaze phase is the one that results in the greatest risks. These hazards include the possibility of deterioration or collapse of the structures, the possible spread of the fire to surrounding areas by flames that escape from doors and windows, the considerable production of sparks and incandescent fragments that can be transported by the wind towards new combustible products, and above all, the great quantity of flammable gas produced that can spark as soon as it is released from the area involved thanks to availability of new comburent.
This latter hazard is well-known and much feared by emergency fire workers, representing one of the most frequent causes of injury to persons and the spread of fire to distant areas.

4.  Cooling down and extinguishing :

The combustible material begins to be depleted while the heat dispersion (through walls and openings) becomes more important. In this phase the temperatures begin to drop with an initially slow and regular progression and then increasingly more rapid until a temperature of 200/300 °C is reached . It is clear that the progression of the blaze, while seemingly easy to describe, is really quite complex and influenced by many conditions that we are summarising below :

• Type, quantity, weight, and placement of the combustible material
• Dimensions and layout of the zone involved in the blaze
• Openings and pluggings/closures
• Contribution of the comburent ( wind, amount of air available, moisture)

Type and number of causes of the sparks.

A blaze, by definition uncontrollable and undesired, is a greatly feared hazard that can be reduced.
Through risk analyses, by assessing the available data, we seek to understand the probabilities of a blaze developing. Risk of fire can be defined simply and easily as the product of the likelihood of the event occurring and the consequences of this event, according to a simplified formula:

BR (blaze)= F x M

Where: BR is the Risk of blaze, F is the frequency and M is the magnitude of the consequences.

Therefore, would seem clear that to limit the risk of blaze it is necessary to intervene on the factors that make it up, namely, on the frequency and limiting the consequences.

Conclusions

SIX ITALIA has a range of products designed to intervene on one very important factor :

" LIMITING THE DAMAGE IN CASE OF FIRE "

In fact, with the range of intumescent and expanding products available, SIX ITALIA can intervene by coating and covering the supporting structures and increasing the resistance of the structures before the collapse temperature is reached.
Among our structure protection products, it is important to remember intumescent bicomponent epoxy paint. EPOSIX BRD is ideal for structures in lightweight alloys and steel. This system enhances the fire protection qualities, while maintaining the distinctive characteristics of the epoxy system unaltered, namely the excellent adhesion to the surface and good mechanical resistance.
EPOSIX SM is an expanding product with excellent resistance to external factors that doesn't require water-proof protection. The product offers excellent fire protection characteristics and has been formulated with acoustic muffling characteristics.
SIX ITALIA also produces a water-based intumescent product, EPOSIX AV, and a solvent-based intumescent product, EPOSIX S.

SIX ITALIA offers a series of panels designed with revolutionary technology for insulating bulkheads or dividing walls with R.E.I. resistance, using the new technologies and new synergies with panels that do not contain glass wool or rock wool fibres.

The SIX TH 2459 panel is composed of a blend of organic fibres with outstanding resistance against high temperatures, SIX FIRE XJ 456 and SIXFIRE XJ 457 panels are based on inorganic extenders and cellulose fibres with extremely good mechanical resistance, ideal for achieving heat resistance in structures subjected to high compression that should never be exposed to direct flames. SIX FIRE XJ 459 is a rigid panel composed of inorganic lamellar extenders and silicon resins, ideal for protection against high temperatures and direct exposure to flames. SIX FIRE XJ 458 is a sublimable panel.
To complete the range of protection products, SIX ITALIA has designed a system of expanding barriers for sealing in case of fire cable channels, pipe channels or holes in walls that must have R.E.I. fire resistance characteristics. The product is composed of a 20 mm thick sheet called SIX FIRE 011 P. This special sheet is easy to work with and can take on any number of geometric shapes without limiting the designer or installation technician in any way. It can be modelled with common woodworking equipment.
The product must always be installed between rigid walls. SIX ITALIA can also provide the system already measured and outlined as per customer requests.

Completing the range of barriers, the SIX FIRE 020 acrylic sealer in cartridge for sealing joints and expanding grills and SIX FIRE GRILL for sealing ventilation ducts.

If you need further information or engineering testing statistics in order to make the correct choice of materials and thickness dimensions, our technical assistance staff and laboratories can help.