Fire prevention

Combustion: A series of rapid chemical reactions between a fuel and oxygen that cause light and heat.Pre-Mixed Flame

If the gaseous fuel is shaped and then mixed with oxygen, it is called a premixed flame.

Diffusion Flame
If the fuel is liquid or solid and mixing takes place during combustion in such a way that combustible vapors are generated, those flames are called diffusion flames.

Flash point:

Temperature is said to be that a fuel must be heated to emit a gas that ignites near a source of ignition.

Fire point:

Temperature is a fuel that must be heated to emit flammable gases to cause a fire.

point :
It is not the fuel that burns, but the vapors from the heating of the fuel that burn. When the ignition starts and the vapors are ignited, the flames generate more heat and the production of flammable vapors increases.

Flammable (or explosive) limits

It is the minimum and maximum density of vapor or gas in the air, which is less or more in case of contact or a live fire, ignition and the space between these two limits for any type of fuel in the ignition or explosion range is called (Flammability Rang These limits are usually displayed as a percentage.Flame point:

The degree is that the complex vapors in the liquid surface have reached a point where they ignite immediately as soon as a live fire approaches, but this flame is instantaneous and does not have enough energy to continue and propagate, and is similar to a hazard valve. In fact, the flash point of the flap point of the fuel vapor pressure curve is the unit of low flammability.

Fire spread:

The three basic mechanisms of fire spread are:

Convection Conduction and Radiation

Convection displacement

Heat transfer is a method of heat transfer through the movement of air. During a fire, hot air expands and moves away from the fire. Usually around 75 /. The heat of a fire is dissipated by ambient air and combustion gases. The rise of hot air causes the fresh air drawn from below to take its place. In large fires, it has turned into heavy loads and terrifying furnaces, which take the flame burners of the door to many distances and cause new fires at long and short distances. In such fire storms, water loses its extinguishing effect because as soon as it encounters this very hot air, it evaporates quickly and moves away with the hot air.
If it blocks the walls and ceiling of the surrounding area, it goes down and covers the lower floors, and in case of high density, the resulting pressure breaks the glass and explodes, and sometimes cracks the walls and ceilings.Conduction: Conduction
It is the transfer of oscillating motion of highly excited molecules to low excited molecules. During a fire, heat can be transferred through steel columns, metal pipes and wires (which are good thermal conductors).

Radiation: Radiation

Radiation is the transfer of heat in the form of electromagnetic waves, such as the transfer of heat from the sun to the planets of the solar system by the passage of radiation. Whenever they hit an object, they may be absorbed and turned into heat.

Fire expansion curve

The period of fire growth lasts from the moment of ignition until all combustion materials are present in the environment. The duration of the expansion period depends on many factors, but the decisive (critical) moment is when the flames reach the ceiling. Emitted under the roof, the amount of radiant heat radiated to the surface of the refractory fuel increased unbelievably, and the temperature reached about 550 ° C. They will ignite in 3-4 seconds. This sudden transfer is called a flashover and is the starting point of the stationary phase of the fire. If the fire is insufficiently threatening during the growing season, the fire may quickly drop from the intense ignition stage due to lack of oxygen and the fire may be completely extinguished, and such a flameless fire can be very dangerous in a closed environment full of flammable vapors. It ignites as oxygen enters the eruption. This reaction is called flame retardation, which can be very dangerous for firefighters who enter rooms to search for and rescue people.

Fire safety targets

For a building safety to be successful, it is necessary to integrate the goals in a perfectly coordinated and proportionate manner. The goals will have aesthetic, practical, technological and economic aspects. In the design to ensure the safety of life, the safety engineer strives to reduce the likelihood of injury and death to occupants of buildings and other persons who may be injured to an acceptable level. The purpose of protecting property and furniture is to reduce the potential for damage to the structure of the building and its contents to an acceptable level. The building must also be sufficiently safe for firefighting operations in the event of a fire.

Fire safety methods There are five ways for safety engineers looking to achieve life and financial safety goals.

1- Prevention: By controlling fuel sources and ignition sources that should be ensured not to start a fire.

2- Communications: Make sure that in case of fire, residents are notified and all fire-sensitive systems will be activated one after another.

3- Rescue and escape: Make sure that the residents of the building and the surrounding area can go to safe areas before they are harmed by heat or smoke.

4. Limiting the fire: Ensuring that the size of the fire is minimal and therefore the amount of equipment and people who may be threatened is limited.

5- Fire extinguishing: Ensuring that the fire can be extinguished quickly and with the least damage to the building..

Acceptance and equality

Absolute fire safety is ideal where there is no danger in any way and access is never possible. Safety engineering never seeks to create such absolute safety, it is enough to reduce the risks to people and their property to a level that accepts the standard. It is obvious that around a certain point, any increase in fire protection standards will increase in proportion to the unnecessary costs to achieve that particular standard. Therefore, fire safety design must achieve a balance between economic safety and compliance with the law. Acceptance must be viewed from the perspective that absolute safety is unattainable, as well as the law of limitation of cost (which is a kind of cost-benefit analysis).

PreventionThe simplest and most effective way to achieve fire safety is to prevent the onset of fire, which is called fire prevention. There are two ways to prevent fire, the basis of which depends on the fire triangle. Removing oxygen from a residential building is often undesirable and impossible, so fire prevention is focused on the other two sides. Preventing ignition and limiting available fuel are two ways to prevent fire.

Ignition prevention:

There are two things to keep in mind when designing to reduce the risk of ignition.

A) Identification of sources of ignition

B) Management of the building in such a way that the risk of ignition is eliminated.

There are four major causes of fire.

1- Natural phenomenon (lightning or thunder)

2- Human errors (smoking, matches, cooking, etc.)

3- Technical defects (failure of wiring and electrical equipment)

4- Intentional fires (suicide, resentment, cover-up, etc.)

Natural phenomena:The most terrible natural source is Azar Khash. Lightning hazards are well known. The average glow time of a lightning bolt is less than a thousandth of a second, but during this time a large amount of electrical energy is transmitted to the earth. (Perhaps a current intensity of about 100,000-10000 amps and a potential difference of about several million volts) When current passes through building materials or the joints and gaps between them, its energy is converted into heat, which is produced in reaction with water containing building materials. It gases very hot. In this case, lightning can damage buildings. Designers should try to have high-risk buildings have an electrical system that transmits the electric shock of lightning directly to the ground. Earthquakes are also a major fire hazard due to the damage they can cause to gas and electricity installations. In acute conditions, buildings may even be threatened by firefighting activities.

Human errors:
Probably the most common cause of ignition and certainly the most difficult cause that can be designed to deal with it is human error. Almost all fires started by tobacco and matches can be avoided, and they are still one of the biggest causes of house fires and subsequent fatalities.
High-risk areas (high flammability such as restrooms and kitchens) should be located as far away as possible from areas with high financial and human risks (such as bedrooms and special storage areas). usage . Where there is the greatest risk of ignition in the kitchen (cooking) and living room (smoking) and the greatest danger to life in the bedroom. The designer should try to avoid escape routes and save the bedroom by passing through the living room and kitchen. .

Technical shortcomings:
Since complete fire safety is unattainable, all services and home systems will inevitably fail one day. It is necessary to design in such a way that predictable defects are controlled and repaired, and the engineer must take this into account in the short and long term life of the building.Annual maintenance and repair of the building is an indisputable measure of fire safety that explicitly specifies what is needed to ensure that all services are maintained to the required standards. Telephone) include elevators and active building fire safety systems (alarms, gas detectors, smoke control, automatic fire extinguishers, etc.).

Intentional fires:There are four categories of intentional fires, some of which are easier to design than others. Intentional fires may be:

1. Material benefits

2. Hiding the crime

3- Revengeful and blind enmities (accidental)

4- It is a terrorist act.

Incitement for financial gain includes fires that are kindled by residents or owners. Insurance scams or attempts to solve companies’ financial problems by destroying factories.Also, the least that can be done is to design fire prevention to cover up the crime.
A person who wants to hide his murder or crime has no intention of setting fire to a building. Unfortunately, there are many fires that are lit for revenge. The fired worker may rightly or wrongly complain or complain to the employer and decide to retaliate by destroying the factory, shop or office.

Three lines of protection can be assumed in the designs for each building.
 First around the building
The second is the outer wall of the building
Third is the boundary between the various parts inside the building.
The last category of public fires is terrorist acts. Fortunately, this phenomenon is rare in most parts of the country, but designers who may be the target of terrorist acts should be aware of this danger. Not only government and military buildings but also small markets and university buildings are at risk.

Limit fuel
It seems that if the building is managed and established only on the basis of the design team, the fire prevention criteria may be more effective. Limiting the amount of fuel available on both sides helps reduce fire risk. The first is by controlling the amount of material that can burn and generate heat to spread the fire. This is called Fuel Fre Load. The second will control the amount of smoke that is produced. The amount of fuel potential that burns to produce smoke is often referred to as the Smoke Load. They are under the control of the management design team1) Skeleton of the building 2) Furniture containing the building

Building skeleton

Unfortunately, it is not always possible to call a substance safe or unsafe. To do this, we need to know more about the conditions under which the material is safe. The safety engineer must be careful in dealing with manufacturers and manufacturers because they simply make sure that a material is fire-proof. The designer must know what the certificate is. And what does it mean?Essential specifications of building materials that can be measured and should be aware of are:

Flammability: The degree to which a substance burns easily when targeted by a flame.

2. Flammability: Whether a substance burns due to the heat given to it or not

3- The amount of fire emission due to the production of heat caused by the substance: When that substance is heated, which depends on the level of heat dissipation, the amount of heat production.

4. Flame surface expansion: How a substance emits flame from its surface.

5. Smoke dimming potential: The degree of limited vision caused by the production of smoke from burning.

6- Fire resistance: Will a component or combination of components withstand fire resistance due to their directional strength (one-way resistance), cohesion and insulation properties?

Building content
A very large percentage of fires start as a result of the combustion of the contents of the building. Therefore, where the prediction of textiles, furniture or building equipment is under the control of the design team, it is important that their role in fire prediction be considered. The dangers of burning furniture and furnishings and decorations depend on their construction. There is no 100% anti-flammable material and the specialist can only try to minimize the risk by choosing the right fibers and upholstery foams.

Special Dangers of Polyurethane Foam This material poses a much greater risk because it generates a very large amount of highly toxic fumes, including carbon monoxide, hydrogen cyanide, and very large amounts of heat when burned, and ignites very small droplets when melted.

Polypropylene backs also produce fires that produce smoke and heat at the same rate, depending on the toxic gases produced by the polymer and how the combustion characteristics of the material are increased.

Fibers are classified based on their resistance to flame. Choose those that are more resistant to fire and do not burn when the flame reaches them, but will melt.Introduction :

Fire safety in the building is possible with the help of design, design and management research. Its field of study is very wide and includes various sciences in various fields. In addition to technical and experimental sciences in industry and construction, administrative sciences, sociological psychology and similar sciences are also used, each of which contributes in some way and to some extent.
Although fire is useful, it can also be deadly. Fire has gravity and range. According to a proverb, in fire is a good servant and a bad master.Human civilization will change drastically without fire and life will have no meaning for it. However, fires that get out of control have a lot of cost and damage. The risk of fire is present to some extent in any building design. It has been proven that complete safety Fire is impossible. However, fire safety is not only an aspect that the building design team must consider, but there are other aspects that must be considered, such as aesthetics, applications, technology, economics, and so on. Successful design These aspects must be fully considered in the design process, appropriate and related.

There are three ways to achieve fire safety

1) Recognize the causes of fire and try to prevent it

2) Identify the reasons for the growth and spread of the fire and try to be safe against it

3) Learning to manage the fire and trying to control and extinguish the fire

In practice, with knowledge and awareness of how fires occur, how they spread and how they can be controlled and extinguished. This is done through separate programs to provide safety. The three methods of achieving fire safety are as follows.

A) Development and implementation of standards and regulations for fire prevention of these activities, such as research and educational efforts on various issues of fire and fire, preparation and regulation of preventive recommendations, administrative methods and safety services. These groups of activities are usually carried out in centers such as universities, fire and firefighting laboratories, scientific and industrial research organizations, research institutes, and sometimes standardization of fire insurance companies.

B) Development and implementation of standards and building regulations for fire protection: In general, these efforts are prepared and planned in order to provide conditions for pre-investigation so that in case of fire, casualties and financial losses due to fire are minimized. These perspectives are not in the realm of research institutes and are more in the realm of organizations that oversee the construction industry.

C) Establishment of fire organizations and development of firefighting measures and trainings:

Fire safety management:

Documentation of decisions already made by the design team to limit fuel and fire prevention is required. A thorough and regular fire safety inspection will be extended, so that fire safety systems and components are regularly inspected. Such visits cause new hazards to be identified inside the building and appropriate criteria to be adopted to control them.

The second part of the fire strategy includes the work that must be done in the event of a fire, and the design team must consider such work in preparing the draft. (Shelter or exit, firefighting or firefighting)


Buildings should be designed so that occupants can be exposed to flames. They must be able to act safely before being trampled by smoke and heat. Therefore, the time required to escape should be shorter than the time of fire release. This is achieved by controlling the spread of fire and providing escape routes that are not long and page by page. Although many people can have enough mobility to evacuate, people with disabilities, chronic patients, or sedentary people need help evacuating.

So there are three general escape strategies

1) Simple exit by escaping directly from the building when the siren sounds

2) Shelter

Use non-combustible building materials to provide a safe place inside the building, so that evacuation from the ward begins when the fire reaches the adjacent area. It is clear that this is only acceptable when further evacuation is possible without returning to the source area.

There is also a third escape strategy that can be accepted as a solution to some of the actions taken to help people through people outside the building. Assistance in small buildings can be considered, which is neither reliable nor commendable.

The width of each exit passage should be considered according to the exit capacity and designed for the maximum number of occupants who may pass through it. To it.

Exit evacuation: Exit evacuation is the part of the exit that is located between the end of the exit and the public passage (an alley of a street). Each exit must lead directly or through the exit evacuation to the public passage.

Fireproof parts of the building, including the roof wall, fire resistant floor that can withstand the burning of all loads of fire located in the space.

Fire Resistant: As long as the materials or a combination thereof are capable of direct fire resistance according to standard.

Life safety concepts:
In the event of a fire, the age, health and mental ability of the residents affect how they react and rush to a safe place. The height of the building also affects the possibility of reaching a safe place because it is more difficult to evacuate tall buildings.

exit way
A continuous and unobstructed path that is considered to reach an open area or public passage from any point of the building.
The exit route consists of three distinct sections: “available”, “exit” and “exit evacuation”.

Exit available
Exit access is the part of the exit that leads to the entrance of an exit. The maximum access length of the exit for places with high-risk contents is 23 meters.

All exits accessible for the evacuation of persons with a capacity of more than 30 persons shall be separated from other parts of the building by a structure or at least one hour of fire resistance, and the doors to which they shall be opened shall be protected for at least 20 minutes. These doors should be designed and installed in such a way that the possibility of smoke leakage from them is minimized.

Exit :
It is the part of the exit that is separated from the other parts of the building and provides a safe and protected passage space in order for the occupants to reach the exit part of the exit, which are exit ports: exit passages of exit stairs that protect against expected fires in other parts of the building. Have been.

Exit separating structures in buildings with a height of 4 floors and more and buildings with hazardous occupancy must be separated from non-combustible walls by fire resistance for at least 2 hours. In cases where the entire building is protected by a sprinkler network, the fire resistance time is reduced to one hour. All buildings with 4 floors and more.

Number of exit routes
In the event of a fire, residents should be able to either leave the building or take refuge in a place where fire and smoke do not penetrate. Each exit must lead to a guarded path, guarded stairway or outside the building.

Allowed room or space                                                                  Minimum number of outputs

underground                                                                                              2

50Resident or more                                                                                 2

500 Resident or more                                                                              3

1000 Resident or more                                                                             4

For each floor of the building                                                                            2

Exit staircase design strategy

Central staircase: The central staircase is an undesirable escape strategy, because the exit can not be used if the corridor is filled with smoke. But adding an external balcony increases the possibility of salvation.

End stairs: The presence of stairs at both ends of the corridor and two exits creates and most people can take a short way to exit.
Exit stairs: The protected external stairs provide a smoke-free escape route.

Outputs and access to them

The exit to the exit should be free of smoke and fire and residents should always have access to it. The exits should always be far apart so that a fire does not block them all. Place the exits at the end of straight corridors as shown below or at the intersection of two corridors.

Output width:
The standard unit of output width in calculations is 22 inches, which is the width of an adult standing. Note that the adult of the year wants to walk 28 inches because his body is moving. The minimum space for a 32-inch wheelchair is 27 inches for a chair width and 5 inches for hand movement and 33 inches for someone walking with a cane.

Calculate the width of the output unit

The width of the output unit can be obtained from the following formula:
A = Floor area in square feet                             W= A/(DC)
D= Density of inhabitants per person per square foot (according to regulations or actual conditions, whichever gives a larger W width)
C = Capacity per unit output width (number of people who can pass through one point per minute).

Sample issue
An office building with 9000 square feet of infrastructure on each floor is considered. The density of residents (A) is 100 square feet per person and the capacity of the exit staircase (C) is 60 people in the transverse unit of the exit. (Capacity for residential and institutional buildings is less than office buildings because usually the occupants of office buildings are awake, alert and physically capable. How many units should the width of the exit stairs be?
A few tips on the way out
Each apartment building with a maximum of 5 floors above the ground floor with a maximum height of 18 meters with a maximum of 4 residential units on each floor can have only one exit staircase, provided that it complies with the following criteria.

A) Exit stairs should be protected by fire barriers with at least 1 hour of resistance and fire doors with a rate of 1 hour of fire protection, located between the stairs and the building.
B) Corridors used as access access shall have fire resistance of at least 1 hour.
C) The passage distance between the entrance of each residential unit to the exit stairs should not be more than 10 meters.

2) The maximum allowable length of dead-end corridors is 10 meters, unless the whole building is protected by an automatic grate network, in which case this length can be increased to 15 meters.
3) Inside independent residential units, the passage distance to reach the exit access corridor should not exceed 23 meters, except in cases where the building is protected by an automatic rain network, in which case this distance can be increased to a maximum of 38 meters.

4) The number and location of exits should be such that in access access corridors, the distance between the entrance of each residential unit to the nearest exit is not more than 30 meters, unless the whole building is protected by an automatic grate network, in which case the distance The view can be increased to a maximum of 60 meters.

Fire doors
All exit doors must be at least 80 cm wide. In cases where double hinged doors are used, at least one of the hinges should have a useful width of 80 cm. Also, the width of any hinge in a hub should not be more than 120 cm. The floor level on both sides of each door or door should be horizontal and level. Be. It will not be allowed to create a difference in level between the two parts at times up to a distance of at least the transverse size of the largest door hinges.
Doors located at the exit routes must be designed, constructed, installed and adjusted in such a way that they can be easily and urgently opened from the inside at all times of use of the building and no obstructive factor such as locks prevent timely exit or escape of occupants.

Fire doors must be completely closed and locked to be effective against the spread of fire. Doors must be closed automatically. Reinforced glass panels can not have a large surface.

Outlet stairs
All stairs leading to the exit must have a stable structure. The width of the stairs and steps should not be reduced in any part of the length of the path. The footing of all the stairs should be of the same material and with the same type of payment and all necessary measures to prevent slipping on the surface of each stair should be at least 110 cm. Meters of useful width unless the total number of occupants of all floors using the stairs is less than 50 people, in which case the useful width can be reduced to at least 90 cm. Also, each staircase should be at least 205 cm high to the ceiling and the maximum vertical distance between the two consecutive steps should be 370 cm.
The height of the front of the stairs will be at most 18 and at least 10 cm, and the width of each step must be at least 28 cm and at most 2% slope.
They are adopted.

The use of our ramp stairs on the exit routes will be allowed for a maximum of 5 people. Provided that they are designed in compliance with the following criteria.
Useful width of stairs should not be less than 65 cm.
The height of each step should not exceed 24 cm
The size of each step at a distance of 30 cm from the narrowest part of the stairs should be at least 20 cm.
All floor tiles should be the same shape and size.

The time for the residents to leave the building is limited. The maximum length of the allowed path depends on the type of use of the building, the risk of fire and the physical ability and readiness of the residents of the building.

Lighting and marking the exit ways
Output signs should be visible and legible and should never be affected by bright light or blurry and illegible images. Studies by the University of Maryland in simulated conditions show that yellow and orange colors are very effective colors for illuminating exit signs when there is smoke.

All exit accesses must be marked with approved signs indicating the direction of exit with the arrow. The number and location of these signs must be selected so that the distance from any point of access to the nearest visible sign does not exceed 30 meters.

All exits of each building must be marked with exit signs. The sign of each exit must be installed in a position that is easily accessible from all directions.
Exit signs should be simple and understandable to everyone and should show the word exit simply and clearly.
Each exit sign must be adequately lit by a reliable light source
The brightness of the signs, whether from outside or inside, should not be less than 54 lux.

Necessary features for outputs

Resident density is the number of people who must be provided with an outlet. The table below shows the population density (A) in terms of quarters per person for different buildings. If the number of occupants is known at the time of building design, it should be calculated usage . Capacity C) is the number of people per unit of output width that can pass through one point of the output path in one minute. In order for the unloading time to be consistent with the rest of the calculations, the capacity for different buildings from the table below is feared.

Type of density acquisition a)) square feet per person with a capacity of c people per unit width of horizontal exit horizontal exit of stairs
Residential                                                                       200                                                                      60                  45
Educational                                                                                                                                                                       60  
Classroom                                                               20                                                                          100                 60
workshops                                                                    50                                                                                       100    
institutes                                                                                                                                                                                    22
The place of treatment                                                               240                                                   30
Dorm                                                               120                                                        30
Fixed seat                                                                 15                                                  100
No fixed seat                                                   7                                                           100
Standing places                                                    3                                                           100
office                                                                   100                                                       100
first floor                                                                         30                                                       100                                                     
The rest of the classes                                                                       60                                                      100
industrial                                                                         100                                                      100
Store                                                                   300                                                        60
Dangerous places                                              100                                                                     60

Table of occupancy units in different buildings in terms of square meters per person

Restrict fire

Restricting fire to achieve two main goals is fire safety: life protection and property protection, property protection by limiting fire spread and fire resistance in building components, and life protection by limiting smoke emissions and providing shelters inside the building. It is possible for residents to be safe. This concept of shelter is especially important in situations where evacuation from the building is very time consuming or dangerous.

Severe and rapid evacuation of patients out of the hospital may pose a greater risk of death than fire hazards (which we try to avoid). Heat is often very dangerous for the materials and structures of buildings and smoke is also very dangerous for its inhabitants. It is necessary to consider fire control criteria for these hazards and stop the spread of smoke and heat. Active and passive fire-fighting methods may be designed.

In active methods, communication needs to take place in such a way as to inform people and devices about the existence of fire and organize them to take measures to limit the spread of fire. Most active fire-fighting methods are related to smoke control and rely on determining the moment of fire. The most common active fire safety methods are sprinklers (showers) and other methods of automatic fire extinguishing.

Passive methods of fire control are related to the characteristics of the building skeleton, its partitions and its insulation. They extend the life of the building and are often considered as fire retardants. Such passive methods can be considered under the following three groups:

1. Skeletal protection – protection against the effects of heat generated on the basic components of the building to columns, load-bearing walls, floors

2. Dividing – Dividing the building into different parts and fire and smoke resistance resulting from this type of division, interior walls, doors and floors

3. Insulation – protection of the insulation of a building that is created for people, neighboring properties and property, as well as buildings and external walls and roofs and their dwellings (from the fire of adjacent property and furniture).

Passive methods

1. Protection of building components (sketch)

2. Fire resistance

1. Protection of building components (sketch)

The amount of fire protection that is appropriate for building components depends on the need to escape and extinguish the fire. The first is how long it takes to escape from the building. Does the safety of the building depend on the shelter forecast inside the building? Secondly, firefighters need to work inside the building and it is essential that the building skeleton is left standing so the building can be rebuilt after a fire.

If it is necessary for the building to remain only until all the inhabitants have been evacuated, then the necessary skeleton protection may only last for a short time. Working safely in a building requires more protection (for example, an hour or more). The amount of fire resistance that must be created depends on the fuel load of the building. In practice, buildings can be roughly divided into the following groups.

According to the table above, the table below shows the proposed duration of fire resistance (in minutes).

After estimating how long the building skeleton should withstand the effects of heat, it is possible to design skeletal components to create this amount of safety. Another problem with building components in fire is that the constant collapse of the building can increase the load that these components must withstand. If the foundation of a building is designed for durability and survival, in designing the amount of fire protection required, it is necessary to consider the overweight that may result from the collapse of the upper floors on the foundation.

2. Fire resistance

The ability of each part of the building skeleton to remain stable as long as it is affected by heat is defined as the fire resistance of that part and is usually measured by time. In this method, not only the fire resistance of components but also the overall fire resistance must be measured. Be. Fire resistance of a component or set of components: In relation to the ability of its resistance to fire to maintain its load-bearing capacity, its coherence and insulation are measured.
Load Bearing Capacity: is a set of strength and directional resistance of materials against fire.

Load Bearing Capacity: is a set of strength and directional resistance of materials against fire.
Integrity: It is the sum of its ability to resist heat shock and break and maintain its adhesion and continuity.
Insulation of a material depends on its heat transfer.

When considering the fire resistance of a skeleton assembly, safety engineering must keep in mind that there may be significant differences between the performance of the assemblies in the test conditions and the actual conditions. The test specimens are usually new products. This fire resistance should not be compromised during the transportation of production and construction by the effects of mechanical damage, weather or heat transfer. The design should be aware of what is likely to occur during the life of the building and include it in the design phase.

The method of testing and measuring the resistance of building components and members to fire has been published in a booklet entitled ASTM E119 (American Cociety For Testing And Materials). Similar methods have been developed by some other institutions and organizations.

1. National Institute of Standards ANSI Brochure A2.1

2. NFPA Booklet 251

3. American Fire Insurers Association Booklet UL 263

4. British Institute of Standards Booklet BS476

The history of building fire resistance and testing goes back to the years before 1918. In the early 1903s, an international congress under the auspices of a British committee formulated and recommended regulations that standardized various test methods for the first time. This old standard, originally in English, introduces test methods for floors, ceilings and materials used in the building and identifies interior dividers and doors. Based on this, the components, materials used in the building in terms of strength into three groups The main ones are completely resistant, semi-resistant and have temporary resistance.
For example, the temporary resistance limit for roofs or floors was reached when the roof can withstand 815 ° C without additional load for one hour, and if with a load of 820 kg / m2 at 980 ° C Celsius lasted 2 hours. It was semi-resistant in the group. There were stricter conditions for being in the completely resistant group, and that it could withstand a load of 1365 kg / m2 at 980 ° C for 4 hours.

In the 1920s, in order to prevent fires, it was proposed that based on the goods and fuels in each building, rules and regulations such as durability and fire resistance be determined and applied. The fuel in the building should be more than the floor area. The members of the building should be more durable and resistant to fire. To compare and evaluate the fire. Therefore, it was decided to compare the total amount of heat produced by various fuels with the weight of dry wood that produces the same amount of thermal energy.