Safety

The importance of occupational safety and health

Occupational safety and health is defined as the science concerned with preserving human safety and health, by providing safe work environments free from the causes of accidents, injuries or occupational diseases, or in other words it is a set of procedures, rules and systems within a legislative framework aimed at preserving humans from the risk of injury, Protecting property from damage and loss.

Occupational safety and health enters all areas of life. When we deal with electricity or electrical household appliances, it is indispensable to follow safety rules and principles. When driving cars or even walking in the streets, we need to follow safety rules and principles. In educational facilities, we need safety rules, and we can even say that when taking medicines for treatment or food for the growth of our bodies, we need to follow safety rules.

The general objectives that occupational safety and health seeks to achieve:

1. Protecting the human element from injuries resulting from the hazards of the work environment by preventing them from being exposed to accidents, injuries and occupational diseases.
2. Preserving the components of the material element represented in the facilities and the devices and equipment they contain from damage and loss as a result of accidents.
3. Providing and implementing all occupational safety and health requirements that ensure the provision of a safe environment that achieves risk prevention for the human and material elements.

In sum, occupational safety and health aims, as a scientific method, to establish safety and tranquility in the hearts of workers while they carry out their work, and to reduce anxiety and panic attacks that afflict them while they coexist by virtue of the necessities of life with tools, materials, and machines that contain danger that threatens their lives and under unsafe conditions that expose their lives between Time and time to grave dangers.
In order to achieve the aforementioned objectives, the following elements must be present:
1. Proper and purposeful technical planning for the foundations of prevention in facilities.
2. Legislation stemming from the need to implement this technical planning.
3. Implementation based on sound scientific foundations.

What are fires?

Fires usually start on a small scale because most of them arise from small sparks, due to negligence in following fire prevention methods. The things that surround us, in the various locations of our presence and the environment surrounding us in the house, street, school, university, workplace, picnic and recreation places, and other sites, which if the rest of the elements of fire were available to them, they would have caused us and our property huge losses. Therefore, we must take preventive measures from the dangers of fires to prevent their occurrence and eliminate their causes, and achieve the possibility of controlling them in the event of their outbreak and extinguishing them as soon as possible and with the least losses.

Percentage of burns and their area:

The percentage of burns on the body ranges from 18% to the right thigh, 18% to the left thigh, 9% to the left arm, 18% to the back, 18% to the abdomen, and 10% to the head and neck (National Center for Industrial Security Studies – Administration). general training).
Combustion process (ignition theory):-
It is that chemical phenomenon that occurs as a result of the combination of the flammable substance with the oxygen of the air with a certain temperature effect factor for each of the substances, and the temperature of this temperature differs for each substance and is called (ignition point), and it is clear from this that in order for a fire to occur, three elements must be present, which are fuel and heat And oxygen, which is called the ignition triangle: –
1. Fuel: It is found in solid form such as (wood, paper, cloth….etc.) and liquid and semi-liquid states (such as all kinds of grease, oils, gasoline, alcohol…etc.) and gaseous states such as (butane, acetylene, methane ..etc).
2. Heat: i.e. the temperature has reached the degree necessary for ignition and its source (sparks, flames, friction, sunlight, chemical reactions, etc.).
3. Oxygen: Oxygen is available in the air at a rate of (19-21%).
However, recent studies have shown that there are four overlapping factors for the occurrence of fire, not three, and these factors are (fuel – heat – oxygen – chain reaction).

How heat is transferred:

Objects exchange heat with those around them, meaning that their temperature under normal conditions is not constant, meaning that heat is transferred from a hot body to a body that is lower than it in temperature, and this happens by one of the following means:
1. Contact – conduction: – heat transfer by conduction takes place through direct contact or through a conductor, as happens in the case of a hand touching a hot pot, as heat transfers from the pot to the hand through the conductor, and minerals differ in their degree of conductivity, some of which are good conductors of heat while others are non-conductive. Also, heat is transmitted in liquids and gases to change density and according to temperature change.
2. Convection currents: – Heat is transmitted in liquids and gases due to the change in density according to the change in temperature. It is transmitted by convection currents, and the transmission takes place from bottom to top. Heat transfer can be observed by convection, as in the network of hot water pipes in buildings, furnace chimneys, heaters, and the spread of fire in building fires from lower floors to upper floors.
3. Radiation: Thermal rays are absorbed by some bodies and reflected by others. Black or dark bodies absorb more heat than shiny or glossy surfaces. Heat transfer in the air is in the form of waves by thermal radiation, such as light rays. Air does not absorb heat, but transfers it from its source to another. If it collides with an object, if it is dark, it absorbs it, and the temperature rises, but if it is a shiny or polished surface, it reflects the heat to the air.

Methods of extinguishing fires (extinguishing theory): –

It is based on the theory of Etf

A fire is based on limiting the interaction of one or more of the three aforementioned factors that cause the fire, that is, the extinguishing theory depends on breaking the ignition triangle by removing one or all of its sides, and therefore the extinguishing operations are subject to three means:

First: Cooling the fire:
It is intended to reduce the temperature of the burning material, by using water, which is thrown on the fire, and this method depends mainly on the ability of water to absorb the heat of the material in which the fire is burning, and the water when used for cooling purposes encounters two types of changes, as its temperature rises until it reaches its boiling point and its transformation To vapor that rises above the surface of the fire, and this is useful in suppressing fires by decreasing the proportion of oxygen in the air.

Second: Suffocating the fire:
The fire is smothered by covering it with a barrier that prevents air oxygen from reaching it, by the following means:
• Close the ventilation inlets and openings in the fire place to reduce the percentage of oxygen in the air to a rate that does not allow the continuation of the ignition.
• Cover the flammable substance with chemical foam.
• Substitution of oxygen with water vapor, carbon dioxide, dry chemical powders, or halogen fumes.
• The fire can be extinguished by separating the flame from the ignited material by blowing up the place of the fire using explosive materials such as dynamite, and this is the method usually used to extinguish oil well fires.

Third: starvation of fire:
Fire starvation is done by reducing the amount of flammable materials by the following means:
• Transporting goods and materials available at the site of the fire away from the influence of heat and flames, such as withdrawing flammable liquids from tanks in which the fire is located, or moving goods from inside warehouses exposed to the danger of fire and its heat, or removing plants and trees in agricultural lands to stop the flow and spread of fire.
• Removing the flammable materials and removing them away from flammable neighborhoods due to the danger of heat and flame, such as pulling the flaming cotton bales from inside the storage place to another place that does not expose the surroundings to dangers.
• Close the valves of flammable gases.
• Dividing the burning materials into small parts so that they become a group of small fires that can be controlled, such as knocking on burning wood to break them into small parts, or mixing water particles with the surface of flammable liquids.

Causes of fires:-

Among the most important causes that lead to fires, especially in industrial sites, are the following:
1. Ignorance, negligence, indifference and vandalism.
2. Poor and dangerous storage of flammable or explosive materials.
3. Saturation of the workplace with flammable fumes, gases and dusts in the presence of poor ventilation.
4. The occurrence of sparks or an abnormal rise in temperature as a result of friction in mechanical parts.
5. Electrical faults or the presence of flammable materials near electrical appliances used for heating purposes.
6. Tampering and lighting fire near dangerous places or in good faith or throwing away cigarette remnants.
7. Leaving flammable waste in the manufacturing area, which self-ignites in the presence of heat.
8. The presence of liquid waste and flammable oils on the floors of the manufacturing area.

CLASSIFICATION OF FIRE

a. Fire Classification by Type:
Fires are classified according to their type into fires according to categories (A), (B) and (C), which mean, in order, carbon fires (A), flammable liquid materials fires (B), and electricity and metal fires (C).

CLASS (A) FIRES:
They arise in solid materials that are often of an organic nature (carbon compounds) such as paper, wood, fabrics, and other plant fibers, and they usually burn in the form of glowing embers, and they are characterized by the fact that most of these materials are porous and it is easy for them to absorb water, which affects their cooling from the inside. Water is the most appropriate means of extinguishing this type of fire.

CLASS (B) FIRES:-
These are fires that occur with flammable liquids or molten materials. In order to determine the most appropriate materials for extinguishing these fires, flammable liquids can be divided into two types:
• Liquids soluble or miscible in water.
• Liquids insoluble with water.
In light of this, it is possible to determine the type of appropriate extinguishing media, including water sprays, foams, halogen fumes, carbon dioxide, or dry chemical powders.

CLASS (C) FIRES:
These are flammable gas fires, including liquefied petroleum gases such as propane and butyrate. Foam and dry chemical powders are used to confront gas fires in the liquid state when they leak on the ground. Water sprays are also used for cooling gas canisters.

CLASS (D) FIRES:-
They are fires that occur with minerals, and water is not used due to its ineffectiveness, and its use has a risk, as is the case when carbon dioxide gas or dry chemical powders are used on bicarbonate, and graphite powder, talcum powder, dry sand, or other types of dry chemical powders are usually used to extinguish This type of fire.

B. Fire Classification By Size:
To determine the size of fires, the following points are taken into account:
1. A massive fire that requires the use of twenty or more launchers.
2. A large fire using nine to nineteen launchers.
3. Medium fire requires the use of three to eight rounds.
4. A small fire that requires the use of one or two launchers or three or more from first aid lines.
5. A minor fire that requires the use of a line or footsteps to extinguish or the use of manual extinguishers.

Dangers resulting from fires:

1- Personal danger: – (risk to individuals) which are risks that expose the lives of individuals to injuries, which necessitates the provision of measures to escape from dangers when a fire occurs.
2- Destructive danger: – the intended

The destructive danger is what occurs in terms of damage to buildings and facilities as a result of fire, and the severity of this destruction varies according to the contents of the building itself of materials that can spread. Ma’in varies the degree of impact of fire in it as a result of many factors, including the type of materials in it, the extent of its combustibility, the method of its distribution inside the building, as well as its economic value. All of this means that the quantity and nature of the building’s components are what control the severity and continuity of the fire, and the destructive effect that results from it.
3- Exposure Danger: – (Danger to Neighborhoods) These are the risks that threaten the sites close to the location of the fire, and therefore it is called the external danger, and it is not required that there be direct contact between the fire and the building exposed to danger. This risk usually arises as a result of the exposure of the combustible materials that it consists of or that the building contains to the heat and flame of an external fire. Therefore, when planning the establishment of a fueling station, it is taken into consideration when establishing it that it be in a non-residential area, or that the residential buildings be at a certain distance, as it is assumed that these buildings will be exposed to a great danger in the event that a fire occurs in this station, and this is what is called the danger exposure.

Symptoms of burns:-
Symptoms resulting from a fire depend on the degree and area of burns. Burns of the abdomen, chest, and head are more serious than burns of the extremities. Death usually results from burns that affect more than a third of the surface of the body.

General symptoms:-
1. Nervous shock, which is slow breathing – dizziness with nausea – cold extremities – pale face – profuse sweating – fast and weak pulse – low blood pressure and body temperature.
2. Bloody shock as a result of insufficient blood reaching the brain due to the widening of the blood vessels in the abdomen, causing a severe drop in blood pressure. This shock is aided by the loss of a large amount of blood plasma from the burn.

Fire fighting devices and equipment:

Mobile Manual Fire Extinguishing Equipment:-
It is the portable “primary control” manual equipment that is used to fight fire in its early stages by ordinary people present in the building. The manual extinguisher must be in conformity with the standard specifications approved by the competent authorities. The types of manual extinguishers are divided into:

1- Pressurized water extinguisher (A):-
It is a cylinder filled with water under inert gas pressure, and is used to extinguish wood, paper, textile and plastic fires.. Beware.. This type cannot be used to extinguish fires of electrical appliances and equipment connected to live electric current or oil, grease or metal fires, and the water extinguisher works to reduce the temperature The temperature of the burning material.

2- Carbon Dioxide Extinguisher (BC):-
It is a steel cylinder that contains carbon dioxide gas that has been compressed to the point of liquefaction, and is used to extinguish fires in oils, grease, dyes, electricity and flammable liquids. Carbon dioxide gas suffocates the flame and cools the temperature. It is released at a temperature of (76 below zero), the extinguisher has a weak effect in the open air, dissipates by the wind, and makes a strong sound when used.

3- Foam extinguisher (B):-
It is a cylinder filled with water and organic materials that produces foam. The extinguisher is used to extinguish fires in oils, petroleum, grease, and dyes.. Be careful.. The extinguisher cannot be used with electrical equipment fires connected to live electric current. It isolates the surface of the material from oxygen and cooling because it contains water.

1- Dry chemical powder extinguisher (D):-
It is a cylinder filled with dry chemical powder. It is used to extinguish fires of alcohol, petroleum, dyes, flammable materials, and metals (magnesium – sodium – potassium). It works to isolate the surface of the burning material.

2- Halon extinguisher (fumes quenched liquids):-
It is not preferable to use this type because the fumes generated from it are toxic and affect its users, especially in closed places. Because it is based on chlorine, fluorine, and bromine, all of which are toxic gases that affect the ozone layer. Although it is a good extinguisher for all kinds of fires.

3- Fire Blanket:-
A fire blanket (fire blanket) is used in kitchens. The blanket is pulled from inside the box, opened completely, and the fire is covered with it to prevent oxygen.

Fixed (automatic) fire extinguishing equipment:-

Extinguishing systems that produce water or other extinguishing media that are suitable for the type of materials subject to combustion (carbon dioxide CO2 for example), that work automatically to extinguish fires as soon as they break out and have an effective effect in protecting the site from the interaction, development and spread of fires. The water-producing extinguishing systems release quantities of water mist to spread over the burning material, thus reducing its temperature below the ignition point. Other extinguishing systems work on the rules of suffocation, cooling, and spoiling the ignition atmosphere. Water-producing extinguishing systems can be installed in all locations that are not affected by water, as they control fires quickly and effectively, and have an effective effect in reducing the concentration of fire smoke and toxic gases emitted from it by the effect of emitted water vapor and extinguishing water spray.

Extinguishing rollers: – They are extinguishing means used to combat fires of the first type and work on the basis of reducing the temperature of the burning material. The extinguishing materials used in them are water and it is forbidden to use them to fight electrical equipment fires. It is found in most buildings and facilities, and it is one of the main and important protective equipment in various locations.

How to use manual fire extinguishers:-

Here we summarize some information related to the operation of the extinguishers:
1. When using extinguishing devices, the location near the fire must be chosen so that this location is safe and easy to fire

Retreat when necessary without effort or hardship, preferably as close as possible to doors or other exits, and if the fire is outside the building, the location of the extinguishing devices must be above the wind level.
2. Reducing a person’s stature when fighting a fire is one of the useful means to avoid the danger of fire smoke and its heat, as it facilitates him to approach the fire site.
3. It must be completely ensured that the fire is extinguished before leaving the site so that it is not expected to ignite again.
How to use water extinguishers: – This is by aiming impulsively from the extinguisher below the flame sites, and the direction is changed in all the area in which the fire is burning, and the hot parts are submerged in water after extinguishing the fire flame. In the case of fires that spread in a vertical direction, the lower parts must be fought, then direction up.

How to use foam extinguishers:-

In the case of a burning liquid inside a container, the foam should be directed to the inner wall of the vessel above the liquid level so that foam can form and spread over the surface of the liquid. When this is not possible, foam can be thrown above the fire site so that it can fall above the surface of the liquid where it settles and forms a cohesive layer. And it is taken into account not to direct the foam directly on the surface of the liquid, because this causes the foam to rush below the surface of the burning liquid, where it loses many of its effective properties, in addition to the possibility of the burning liquid scattering outside the container.
How to use dry powder, carbon dioxide and solidified liquid vapor extinguishers:-
In the event of fires with containers containing flammable liquids, or when these liquids are spilled on the floors, the extinguisher (dry powder – carbon dioxide – vapors of extinguishing liquids) should be directed towards the nearest side of the fire, then a quick scavenging process is carried out towards the farthest side, and this movement is repeated until it is extinguished If the fire is in a liquid falling from a high level, the extinguisher must be directed to the lowest point and then moved quickly to the top. When a fire occurs with electrical devices and installations, the extinguisher should be directed in a straight direction towards the fire. with the body of the cover so that it can penetrate into the interior.
How to use a fire blanket: – Holding the fire blanket is from the upper end near the surface of the burning material, and the blanket is moved from the upper side and carefully to cover the burning object or container.

Fire extinguisher care:

We must know the components of the fire extinguisher, which are:
 The body of the extinguisher: – It is the metal body that contains the extinguishing materials.
 Hose: – It is the part through which the extinguishing materials pass from the body of the extinguisher to the ejection nozzle. (Smaller sized extinguishers may not have a hose.)
 Safety pin: It is the metal ring for fixing the operating arm, which is designed to prevent the release of extinguishing materials as a result of wrong pressure on the operating arm.
 Carrying handle: It is the fixed metal part that is used to carry the extinguisher.
 Operation Arm:- It is the movable metal part that is above the carrying handle, and it is a tool for operating the extinguisher and releasing extinguishing materials.
 Pressure indicator: – It is the part that shows the validity of the extinguisher (it is noted that the pressure indicator is present in all standard extinguishers, except for the carbon dioxide extinguisher, whose validity is tested by weight or maintenance).

 

Fire alarm and detection systems

 

a. The purpose of fire alarm and detection systems:
The main purpose of these systems is to quickly respond to a fire, then convert this early response into an audio and visual signal to alert an individual or group of individuals present in the building, place, relief or firefighting center that there is a fire in its early stages, and man is the greatest fire detector on earth Because God loved him from the senses of hearing – touch – smell – taste – vision in addition to the mind. It is a group of senses that cannot meet in any detector except that a person is in constant motion and may not happen to be in the place of the fire or be sick or asleep or in a mental state that does not allow him to detect the fire, and of course the fire detectors cannot distinguish the cause of the fire or evaluate its intensity, and therefore false alarms of these detectors may cause some problems that in fact do not reflect an error from the detection, but may be due to the selection of inappropriate types of reagents or random distribution of them without studying this. It was agreed that the audio signal of the fire detector must be It is higher than the prevailing sound level in the region by (5) decibels, in addition to the need for these detectors to be designed in accordance with international standards and tested under the supervision of well-known testing laboratories.

B*- Fire stages: Most fires go through four distinct stages:
• PRELMINARY STAGE
• SMOKING STAGE
• FLAME STAGE
• HEAT STAGE

Primary stage: – This stage is devoid of seeing smoke or flames or even feeling the heat, but what happens in this stage is the generation of a quantity of combustion particles as a result of the chemical analysis process, which are bodies that have size and weight, but are difficult to see with the naked eye due to their infinitely small size, and they may grow rapidly. stage or slowly over a period of time that may not exceed a few minutes, and ionization detectors respond to this stage.

The smoky stage: – With the continued development of the fire, the amount of combustion particles increases to the extent that they can be seen with the naked eye, which is what is called in this case (smoke), but until this stage no flame or heat is observed, and the photoelectric detectors respond to this stage.
Flame stage: – With the development of the fire and its growth more and more, it reaches the ignition point and the appearance of the flame, and at this stage the fumes rise and the sensation of heat increases, and the infrared detectors respond to this stage.

Heat stage: – In this stage, a large amount of heat, flame, smoke and toxic gases are formed

This stage is characterized by its very rapid development, which does not take more than a few seconds, in addition to the fact that the transition of the flame stage and its transformation into a heat stage usually takes place very quickly, and the heat detectors respond to this stage.

C*- Alarm systems: Alarm systems detect and control fire and are divided into two systems:

1- System Conventional: It is the system that depends on the set of detectors connected to each other on a specific area, giving a warning on this area through which the security man moves in this area and discovers the location of the fire.
2- The Addressable System: It is the system that relies on a set of detectors connected to each other in the area that takes the numbers and names of the places in which the detector is located so that when a fire appears on the control panel, a statement of the detector number, the name of the area and the time of the fire occurrence appears, and on that these two systems depend on me:

(a) Control Panel:-
• It controls the system, feeds it with the necessary efforts, and monitors its work, as it receives alarms from the detectors, and operates the bells, sirens, and indication lamps.
• * A sound and light alarm is given when a fire occurs, specifying the area of its occurrence.
• * It operates on the city’s electric current (220 volts, 50 Hz) and is equipped with backup batteries that work automatically in the event of a power outage, and it has a charging device that charges the batteries when the power returns.
• * Equipped with the possibility of self-test and gives an audible alarm signal in the event of a malfunction in the board or in any part of the system components or in the event of a power outage or disconnection of the batteries.
• * Equipped with a key to give a general warning to evacuate the site.
• * Equipped with a set of “Rublehiyat” pickups to stop the air conditioners and disconnect the electric current.

(b) combustion products detectors:
Combustion products detectors include a group of devices called fire detectors. The operating system of these detectors is designed to work when it detects one of the four main products of combustion, which are:

1 – Ionized Gases Detectors:
The phenomenon of fire is what occurs from the ionization of molecules when subjected to combustion, and these molecules are imbalanced in the electron, which makes them tend to steal electrons from other molecules, and ionized gas detectors use this phenomenon in operating this type of detectors, and there is in the detector a sensor room equipped with a small hole to enter the air located in the room or place to be protected. Next to the chamber opening from the inside, there is a small amount of radioactive material that ionizes the air of the detector room. Inside the detector there are also two electric plates, one of which is positively charged and the other negative, and the negative plate is located at a closer distance to the source of the radioactive substance. to the positive plate, causing current to flow between the two plates continuously.

And when a fire occurs and the ionized fire products enter the detector chamber, and since they are unbalanced (i.e. need electrons), they work to capture the electrons passing between the two plates (which work on the flow of current), which leads to the cessation of the flowing current and the alarm.

2- Smoke Detectors: Smoke detectors are manufactured using a photoelectric cell coupled with a specific light source. This cell is a flat disk that converts the light shining on it into an electric current. This cell is used in two ways to detect smoke:
• The first: using the beam.
• The second: depending on the resistance of the beam Refractory and its dispersion.
The beam method relies on shining a light beam across the area to be protected until it reaches inside the photoelectric cell, and since this cell works to convert this beam into an electric current permanently (as long as the beam is shined on it) and this current is used to keep the circuit switch open, and when smoke intercepts the path of the light beam The electric current stops, which leads to closing the circuit and triggering the alarm. The beam resistance method depends on the use of the photocell in an inverse way, where a light beam is passed inside a small room so that it does not shine on or collide with the photocell, and therefore there will be no electric current as a result. As for the circuit switch in this type, it is electronic and remains open as long as there is no There is a flow of electric current, and when smoke enters the room, it disperses the light beam and disperses it in a random manner, which leads to part of the scattered light beam falling on the photovoltaic cell and turning into an electric current that locks the electronic switch and triggers the alarm.

3- Heat Detectors: Heat Detectors are the abundant resulting heat of combustion that is detected by certain devices that use the three primary principles of heat physics: heat works on the expansion of materials, and heat works on melting materials, and also through which the thermoelectric properties of a hot metal can be detected, and therefore there is Three groups of devices that use these principles in detecting fire are:

Constant temperature.
• The rate of temperature rise.
• Mixture constant temperature/rate of temperature rise.
• Optical detectors: Light Detectors
Fixed Temperature: Fixed Temperature detectors are designed to operate at a specific temperature.

The first type: – constant temperature bimetallic, in which two metals or two alloys are used, each metal or alloy has an expansion coefficient that differs from the other when heated, and the two metals are formed into thin slices united with each other to form one slice, and the effect of heat allows the expansion of the metal with the largest expansion coefficient to be It expands at a faster rate, which leads to the curvature of the slice towards the side of the metal with the lower coefficient of expansion. Then the amount of curvature and the difference in expansion between the two metals are calculated at a specific temperature. the

Two electrical connectors when a certain amount of curvature is reached and an alarm is triggered.

The second type: – This type is based on the principle that most metals melt when exposed to heat. Moreover, the melting point of most metals is very specific, meaning that the melting point of the solid does not change, and soft metal alloys (with a low melting point) are used for this purpose after they are Adjusting the components of the alloy until a specific melting point is achieved, after which the alarm sounds.

The third type: – This type depends on the expansion of solvents by heat, where the solvent expands and begins to evaporate when exposed to heat, which leads to an increase in vapor pressure. At the same moment, it also records the temperature at which the pressure led to shattering the glass. Thus, the specific temperature for breaking the glass can be determined. This bottle is then placed inside the detector to separate the two connectors. When the glass is broken, the two connectors close the circuit and an alarm is sent. Constant temperature detectors can be largely relied upon, but their sensitivity is very low, and most of these types of detectors must be replaced after sensing a fire.

Rate Of Rise Detectors

Rate of rise detectors depend on the expansion properties of heat, the main exception being the thermoelectric rate of rise detector. Most rise rate detectors use a small, air-filled chamber with a thin, flexible metal diaphragm at the bottom. These are known as pneumatic rise rate detectors. When the air expands inside the room, the membrane is pushed by force in the external direction, and when the membrane is pushed to a predetermined level, it forces a group of electrical conductors to open or close the circuit, and this change in current works to send a signal to the alarm board.
The first type is called “Spot Detectors.” These detectors look like a hemisphere, and their color is copper. It must be taken into account that if they are painted in any color other than the factory color, they must be replaced immediately, as the coating of any detector affects its ability to sense and detect heat. .
The second type uses a tube extended over the area to be protected, and the space inside the tube acts as a room, and the tube is connected to an operating container with a flexible membrane that works with the same idea as the previous membrane. There are also many other types that work on the same foundations and rules mentioned above.
Reagents group (mixture) rate of rise and constant temperature: These detectors work according to the name given to them on the basis of the rate of temperature rise and the idea of constant temperature, and this allows and enables greater sensitivity of the detector.
Light Detectors: Light detectors are also called flame detectors. There are two main types of photodetectors:
The first: detects the light in the ultraviolet spectrum
The second: detects the light in the infrared spectrum Infrared: ultraviolet detectors work to detect light electronically for short light waves that cannot be seen by the eye, and these waves are usually accompanied by a very dense flame. The problem with this type of detector is that ultraviolet radiation is found in sunlight and welding arcs, which affects the detector by giving false alarms, so it is preferable to use this type in places that are not affected by the external environment. Infrared detectors work more efficiently when separated from the sources of ignition sources, which makes their use in monitoring large areas very effective. The detectors trigger an alarm when they receive infrared radiation.

 

Aid for burn cases: – The injured person is thrown on the ground, covered with blankets to keep warm, and transported to the nearest hospital.

Objective treatment:-

1. Minor burns: – The wound is cleaned with an antiseptic solution and covered with oil and Flavin 1000 / or Paraffin 1000 / 1 solution or gentiania tincture or sprinkled with antiseptic powder.
2. Severe burns: – He does not resort to topical treatment until after the nervous shock has subsided. The victim is given an ampoule of morphine, and the burn is covered with a clean towel or sheet, and he is quickly transferred to the nearest hospital.
3. Burns of the mouth and pharynx: – It results from drinking hot liquids or consuming caustic substances, which are very dangerous because of the swelling and narrowing of the larynx, which leads to suffocation. First aid:
The injured person is placed in a steam tent, then cold compresses are placed on the neck, after that olive oil or paraffin oil is taken in the mouth.
(National Center for Industrial Security Studies – General Administration for Training)

Safety in educational facilities:

The sensory environment of educational facilities includes the school construction site, buildings, halls, classrooms, gymnasiums, field workshops, scientific laboratories, furniture, equipment and school tools. The following summarizes a set of safety rules and procedures in general, which must be applied during the construction and use of educational facilities to ensure the availability of safety for their users and to preserve the facilities and the devices and equipment they contain from damage or loss. This is due to the multiplicity of risks that students may be exposed to in educational facilities, and these risks in educational facilities can be classified into:
Physical risks, engineering risks, chemical risks, health risks, and personal risks, which are the damages that affect students and users of educational facilities as a result of indifference to the application of occupational safety and health procedures or lack of awareness of them due to the absence of awareness programs, and fire risks that may threaten the lives of students and users of educational facilities Risk, loss and damage to property as a result of the absence of safety requirements when constructing educational facilities or not equipping them with alarms, firefighting and training teams inside the school.

For schools on how to act in cases of fire.

Fire prevention guide and method of action in the event of a fire:

Workers must be aware of the actions that must be taken to prevent the occurrence of a fire, as well as how to act in the event of a fire, including the procedures for announcing and notifying of the occurrence of fire, evacuation rules, and preliminary fire control measures until the arrival of the competent firefighters. Training all workers on these actions is a must to ensure that they carry out their duties when an occurrence occurs. a fire:-
1. Inspection and periodic examination of work places: The periodic inspection of all work sites, even if all buildings are properly designed and equipped with fire protection requirements, is one of the most important tasks of the Occupational Safety and Health Committee, and the inspection must include the following cases:
• Storage operations, especially flammable materials, materials that help ignition, or materials that self-ignite.
• Sources of sparks and other sources of heat.
• Ensuring the availability and safety of fire extinguishers and their suitability for operation
Ensure the implementation of general hygiene instructions, collection and disposal of exhausts, etc
2. Hygiene, prohibition of smoking, carrying matches and lighters, and proper storage:
• Smoking must be completely prohibited in workplaces where flammable materials are available.
• Placing signs (no smoking) in areas where smoking is prohibited and implementing these instructions accurately from supervisors, visitors and employees.
• It is forbidden to carry matches and lighters in places where smoking is prohibited.
• Do not store flammable materials in open or glass containers (dry spills of these materials quickly and do not store them near heat sources such as stoves and heaters).
• Always maintain the necessity of not having any leaves or waste on roofs, in gardens, or around buildings, for easy use with any spark you touch.
• Make sure to extinguish matches or leftover cigarettes before throwing them into the containers designated for this purpose.
• Waste must be burned in special incinerators and not in the open air, especially on windy days or at a distance of less than 50 feet from buildings.

Pay attention.

1. You must make sure that the fire extinguisher is valid, because it is the loyal companion to protect you from fire the moment it occurs.
2. Watch the indicator on the extinguisher – as well as the weight of the CO2 extinguisher.
3. Watch the maintenance date on the extinguisher.
4. Contact the specialized company every 6 months to perform preventive maintenance on the extinguisher.
5. Contact the specialized company immediately to refill the fire extinguisher when it is used and to empty its packaging.
6. Locate your existing firefighting equipment and set a numbering system for them.
Anyone who discovers a fire must do the following:
1. To break the glass of a fire alarm to turn it on.
2. To immediately call the emergency phone number to summon the fire brigade.
3. To fight the fire, if possible, by using the nearest extinguisher suitable for the type of fire, as follows:
• Hold the extinguisher well by the carrying handle.
• Pull out the safety pin on the extinguisher.
• Point the nozzle of the extinguisher at the base of the flame.
• Press the handle to turn on the extinguisher.
• Move the extinguishing materials on the base of the fire left and right
4. To make sure that the place in which he is standing does not constitute a danger to him and that he can escape if the fire spreads.
5. When using a manual fire extinguisher outdoors, stand with the direction of the wind at a distance of two to three meters from the fire.
How to behave if it caught fire?
1. Do not try to extinguish a fire unless it is small and you are confident that you are able to put it out.
2. If the fire was large. He left the room and closed the door behind you and fill warning device.
3. In the event of heavy smoke, rolling on the ground is the best way to get fresh air.
4. Feel the door and handle with the back of your hand. If it is not hot, open it carefully and exit.
5. If you find the door hot to the touch, do not open it.
6. Take down the curtains and open the room to ventilate it and expel smoke.
Safety requirements that must be met when preparing a fire protection project in industrial, commercial and administrative facilities, schools and homes:
When starting to think about constructing any building, safety rules in this building must be taken into account in the first place, which requires a good study of the nature of the building and identification of the extent of its exposure to the risk of fire, and this requires studying the activity carried out inside it, its stages, and the properties of the materials used in terms of their danger and the extent of their combustibility, as well as The number of workers in the place or residents of the building, their locations, and the extent of their exposure to danger in the event of a fire. In the light of this study, recommendations are approved

To be implemented to prevent fire risks, according to the following principles:

Recommendations related to escape routes: – Escape routes are considered one of the vital issues because they relate to the safety and security of lives inside buildings, so they should be given adequate care and it is necessary to determine the number of workers in each part of the building. fire to a place where they find safety and security, including the following recommendations:
1. The doors should open to the outside and be easy to open, and it is not allowed to install them in a way that makes it impossible to open them. It may be required that the doors be left open throughout the work period if the matter requires that (if the activity carried out is very dangerous)
2. Fit thresholds and hallways leading to stairs or doors.
3. Removing obstacles to exits.
4. Clarifying the locations of the exits used as escape routes, along with clarifying the way to open the doors.
5. Install smoke-proof partitions and doors in the ways leading to the escape routes (from fire-resistant materials for at least half an hour and remain permanently closed and close the openings tightly – installing fire-resistant glass for the doors or openings).
6. Stairs, their adequacy and recommendations required.
Recommendations related to lighting and electrical equipment:
1. Determine the condition of the electrical installations and equipment and the extent of their conformity with the technical principles.
2. Temporary emergency connections are given importance.
3. Scan forFuse plates to assess their conformity with technical assets.
4. Recommend that the building be equipped with safe electrical installations that prevent the occurrence of thermal radiation from lamps or the emission of other thermal effects in places that contain vapors, gases, or flammable or explosive dust.
5. Recommend the provision of back-up lighting, if necessary, for the locations of the escape routes.
6. Lighting by mobile (manual) batteries.
7. Availability of an easy way to cut off the electric current, so that it can be used easily when necessary.
8. Ensure that periodic maintenance of electrical installations and equipment is carried out on a regular basis.
9. Recommending illumination of panels illustrating the escape routes.
With regard to the role related to the firefighting sector, it is based on:
1. Study working conditions and potential fire hazards, and develop solutions and proposals necessary to confront and eliminate such conditions.
2. Protecting all the company’s sites from the dangers of fire and explosions by providing appropriate means of extinguishing for each site.
3. Carry out control and control work on fire sites to prevent its spread and limit losses by all available means.

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