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Classification of fires. Class A and B

Sea hydrological phenomena. The hydrological phenomena on a land. Biological phenomena. Natural fires.

Sea hydrological phenomena:

- cyclones, typhoons;

- sea level fluctuation;

- strong ice in port or a separation of coastal ice.

The hydrological phenomena on a land:

- floods;

- increase of level of ground waters or water level reduction.

Natural fires:

- forest and steppe fires;

- land and underground fires on peat lands, in oil and coal layers

1.Hydrology is the scientific study of the movement, distribution, and quality of water on Earth and other planets, including the hydrologic cycle, water resources and environmental watershed sustainability. A practitioner of hydrology is a hydrologist, working within the fields of earth or environmental science, physical geography, geology or civil and environmental engineering.

Surface-water hydrology is a field that encompasses all surface waters of the globe (overland flows, rivers, lakes, wetlands, estuaries, oceans, etc.). This is a subset of the hydrologic cycle that does not include atmospheric, and ground waters. Surface-water hydrology relates the dynamics of flow in surface-water systems (rivers, canals, streams,lakes, ponds, wetlands, marshes, arroyos, oceans, etc.). This includes the field measurement of flow (discharge); the statistical variability at each setting; floods; drought susceptibility and the development of the levels of risk; and the fluid mechanics of surface waters.

Biologicalprocesses, properties, and characteristics of the whole organism in human, animal, microorganisms, and plants, and of the biosphere. Examples Biological Processes; Ecological and Environmental Phenomena; Pigmentation; Recovery of Function; Species Specificity;Tissue Survival

Fire - a spontaneous, uncontrollable human spread of fire. They are classified into natural fires (wood, peat, prairie, field) and fires in populated areas (individual, mass, solid).

Fire is a significant force in the forest environment. Depending upon specific land management objective, plus a host of environmental variables, fire will sometimes be an enemy, at times a friend, and frequently its effects will be mixed between the two extremes. Natural fires

Dangers of technogenic character. Traffic accidents. Accidents with the release of chemically hazardous substances. Accidents with the release of radioactivity hazardous substances. Explain by examples.

Traffic accidents.

The most dangerous due to mass distribution and use is road transport. According to WHO in the world die every year because of accidents around 250 thousand people.

Violation of traffic rules:

1. Alcohol

2. Exceeding the permissible speed

3. Mobile talking

4. Smoking

5. Listening to music

6. Eating

7. No using of belts

 

Accidents on chemically hazardous facilities.

By chemically hazardous facilities include:

- Chemical, petrochemical and refining industries;

- Enterprises equipped with industrial refrigeration plants, wastewater treatment plants and waterworks, which use chlorine to disinfect water;



- Warehouses and bases with stocks SDYAV;

- Railway station with rolling chemically hazardous substances.

 

 

Radiological accident - an accident, associated with the release of radioactive products and (or) release of ionizing radiation envisioned for the normal operation of radiation dangerous object boundaries in quantities exceeding the established limits of safety operation of the facility.

The main causes of accidents in RNO are:

- Human error during operation;

- Failure and poor designs.

With radiation accidents possible radioactive contamination (HR) environment - air, soil, vegetation, water sources, buildings, and people, their clothes, shoes, leather covers, mucous membranes and into the organism.

 


15. Ecological, social and global dangerous: Nature and Differences.

Characteristic of global problems: demographic, ecological, wars and terrorism, social (drug addiction, alcoholism, AIDS, etc.).

In the natural sphere the problem of natural disasters is sharply shown. Natural disasters regularly lead to human losses and a huge economic damage to many countries, and, purchasing scale of natural disasters, sometimes in a fatal way affect destinies of the people. The heaviest and hard-to-solve in 21 centuries environmental problems are considered. Manifestation of ecological crisis are diverse, are accompanied by numerous dangers to mankind, are fraught with a global ecological disaster. There is a pollution of soil by hazardous substances. The phytoplankton a basis of a food chain at the ocean and an important source of oxygen perishes Atmosphere pollution proceeds, temperature inversions, oxygen hunger in the cities are observed, acid rains drop out. The irreplaceable loss is caused to the planet biosphere, its genofund is impoverished. Degrade, and even many animal species and plants disappear, biological diversity falls. The woods the most important regulator of environment are reduced. Ecological trouble concerned also circumterraneous space it is saturated by "space debris" the fulfilled artificial heavenly bodies.

Other global problem demographic. The most menacing component of this problem is uncontrollable growth of the population of a planet. Uncontrollable growth of the population of a planet conducts to an overpopulation and an acute shortage of limited resources of Earth for providing the increased mass of her inhabitants. In RK this problem while is shown by a return tendency there is a decrease in population. The demographic problem has two more parties fraught with dangers intensive aging of the population and growth of number of people of disabled age, population shift. The problem of technogenic danger is generated by quantitative and high-quality growth of world economy. This extensive growth is accompanied by high level, and at times and increase in accident rate in many types of productive activity, has the high social and economic price of accidents and technogenic catastrophes. In our country as the main similar reason considerable development of a resource of fixed assets which reached 50-80 % acts. They are that in the world the wide circulation received the phenomenon in case of which the organized communities and groups, and also singles try to achieve the social, political or economic targets by application of threats and violence. In modern conditions the terrorism is the most dangerous version of the political extremism loss of human life, sufferings of people, an economic damage, destabilization and society intimidation appear which consequence

16. Fire is the rapid oxidation of a material in the exothermic chemical process of combustion, releasing heat, light, and various reaction products.[1] Slower oxidative processes like rusting or digestion are not included by this definition. At a certain point in the combustion reaction, called the ignition point, flames are produced. The flame is the visible portion of the fire. Flames consist primarily of carbon dioxide, water vapor, oxygen and nitrogen. If hot enough, the gases may become ionized to produce plasma.[2] Depending on the substances alight, and any impurities outside, the color of the flame and the fire's intensity will be different. Fires start when a flammable or a combustible material, in combination with a sufficient quantity of an oxidizer such as oxygen gas or another oxygen-rich compound (though non-oxygen oxidizers exist), is exposed to a source of heat or ambient temperature above the flash point for the fuel/oxidizer mix, and is able to sustain a rate of rapid oxidation that produces a chain reaction. This is commonly called the fire tetrahedron. Fire cannot exist without all of these elements in place and in the right proportions. For example, a flammable liquid will start burning only if the fuel and oxygen are in the right proportions. Some fuel-oxygen mixes may require a catalyst, a substance that is not consumed, when added, in any chemical reaction during combustion, but which enables the reactants to combust more readily

Fires are classified by the types of fuel they burn.

Class A

Class A Fires consist of ordinary combustibles such as wood, paper, trash or anything else that leaves an ash. Water works best to extinguish a Class A fire.

Class B

Class B Fires are fueled by flammable or combustible liquids, which include oil, gasoline, and other similar materials. Smothering effects which deplete the oxygen supply work best to extinguish Class B fires.

Class C

Class C Fires. Energized Electrical Fires are known as Class C fires. Always de-energize the circuit then use a non-conductive extinguishing agent. Such as Carbon dioxide.

Class D

Class D Fires are combustible metal fires. Magnesium and Titanium are the most common types of metal fires. Once a metal ignites do not use water in an attempt to extinguish it. Only use a Dry Powder extinguishing agent. Dry powder agents work by smothering and heat absorption.

Types of explosions:

Mechanical and vapor/Strictly a physical process, as opposed to chemical or nuclear, e.g., the bursting of a sealed or partially sealed container under internal pressure is often referred to as a 'mechanical explosion'. Examples include an overheated boiler or a simple tin can of beans tossed into a fire. Boiling liquid expanding vapor explosions are one type of mechanical explosion that can occur when a vessel containing a pressurized liquid is ruptured, causing a rapid increase in volume as the liquid evaporates.

Chemical /he most common artificial explosives are chemical explosives, usually involving a rapid and violent oxidation reaction that produces large amounts of hot gas. Gunpowder was the first explosive to be discovered and put to use. Other notable early developments in chemical explosive technology were Frederick Augustus Abel's development of nitrocellulose in 1865 and Alfred Nobel's invention of dynamite in 1866. Chemical explosions (both intentional and accidental) are often initiated by an electric spark or flame. Accidental explosions may occur in fuel tanks, rocket engines, etc.

Nuclear/In addition to stellar nuclear explosions, a man-made nuclear weapon is a type of explosive weapon that derives its destructive force from nuclear fission or from a combination of fission and fusion. As a result, even a nuclear weapon with a small yield is significantly more powerful than the largest conventional explosives available, with a single weapon capable of completely destroying an entire city.

Electrical and magnetic /A high current electrical fault can create an 'electrical explosion' by forming a high energy electrical arc which rapidly vaporizes metal and insulation material. This arc flash hazard is a danger to persons working on energized switchgear. Also, excessive magnetic pressure within an ultra-strong electromagnet can cause a magnetic explosion.

Natural /Explosions can occur in nature. Most natural explosions arise from volcanic processes of various sorts. Explosive volcanic eruptions occur when magma rising from below has much dissolved gas in it; the reduction of pressure as the magma rises causes the gas to bubble out of solution, resulting in a rapid increase in volume. Explosions also occur as a result of impact events and in phenomena such as hydrothermal explosions (also due to volcanic processes). Explosions can also occur outside of Earth in the universe in events such as supernova. Explosions frequently occur during bushfires in eucalyptus forests where the volatile oils in the tree tops suddenly combust.[1]

Animal bodies can also be explosive, as some animals hold a large amount of flammable material such as animal fat. This, in rare cases, results in naturally exploding animals.

 

Classification of fires. Class A and B

Class A- ordinary combustible ortibrous material, such as wood, paper, rubber some plastics.

- Keep storage and working areas free of trash.

- Place only rags in covered containers.

Class B- flammable oe combustible liquids such as gasoline, recourse, pain, thinkers and propans

- Do not trafuel gasoline

- keep flammable liquids sored in a tightly closed container and avay from producing sources

- use flammable liquids only in well areas

 


Date: 2015-12-24; view: 982


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