On August 6, 1945, a giant three-meter uranium bomb was dropped on an unsuspecting Hiroshima ... "A blinding greenish flash, an explosion, everything around
lights up. Silence, and then an unheard-of roar,
the crackle of a blazing flame. under the rubble
people lie in a collapsed building, they die in the flames
women ... A moment - and flared clothes fall from people,
hands, face, chest swell, crimson blisters burst,
and rags of skin slide down to the ground… These are ghosts. WITH
with their hands raised they move in a crowd, resounding the air
cries of pain. A baby is on the ground, the mother is dead. But
no one has the strength to come to the rescue, to lift. Stunned
and the burned people, maddened, huddled together in a roaring crowd and
blindly poke, looking for a way out ... On crippled people
black torrents of rain poured down, and the wind brought a suffocating
stench ... "- this is how eyewitnesses described this terrible event
explosion.
Types of nuclear explosions.
Air.Ground (surface).
Underground (underwater) The center of a nuclear explosion is the point at
which the explosion occurred.
The epicenter of a nuclear explosion
projection of a point onto a surface
earth (water).
The focus of nuclear destruction -
territory subject to
direct impact
damaging factors of nuclear
explosion.
Characteristics of the focus of nuclear damage.
Mass destruction, blockages.Accidents in utility networks.
Fires.
radioactive contamination.
Significant loss of population.
The focus of nuclear damage is divided into zones:
Zone of complete destruction - redundantpressure over
50 kPa.
Zone of severe damage - excessive
pressure from 50 to 30 kPa.
Zone of medium destruction - excess
pressure from 30 to 20 kPa.
Zone of weak destruction - excessive
pressure 20-10 kPa.
Air nuclear explosion.
explosion, glowingcloud which is not
touches the surface
earth (water).
radioactive
area contamination
practically
missing.
Ground (surface) nuclear explosion.
glowing areabang touches
ground surface
(water) and has
hemisphere shape.
Strong
radioactive
infection
terrain and
trail of movement
radioactive
clouds.
Underground (underwater) nuclear explosion.
Explosion made underground (under water).
Main striking
factor - compression wave,
spreading in
soil or water.
Damage factors of nuclear weapons.
shock wave.Light emission.
penetrating radiation.
radioactive contamination.
electromagnetic impulse.
shock wave.
shock wave.
The main damaging factornuclear explosion.
Its source is a huge
pressure at the center
explosion and reaching in the first
moments of billions of atmospheres.
The damaging effect of the shock wave in the lesion:
A zone of complete destruction.Zone of severe damage.
Medium damage zone.
Zone of weak destruction.
The defeat of people by a shock wave:
Overpressure 20-40 kPa - lightdamage (bruises, contusions).
Overpressure 40-60 kPa - lesions
moderate (loss of consciousness,
hearing damage, dislocation
extremities, bleeding from the nose and ears).
Overpressure over 60 kPa - strong
contusions, fractures of extremities, injury
internal organs.
Excessive pressure over 100 kPa - extremely
severe injury, often fatal
outcome.
electromagnetic impulse.
Electric and magnetic fields,resulting
exposure to nuclear gamma rays
explosion into atoms environment
and education in this flow environment
electrons and positive ions.
The damaging factors of the electromagnetic pulse.
Damage to electronicequipment.
Disruption of radio and
radio electronic means.
When discharging fields per person
(contact with equipment) can
cause death.
Protection is shelter.
Light emission.
Light emission.
Flux of radiant energy, includingultraviolet, visible and
infrared rays.
The source is the luminous area,
formed by red-hot millions
degrees by the products of the explosion.
Spreads instantly, lasts up to 20
seconds.
The damaging factors of light radiation.
Causes open burnsparts of the body (1,2,3,4 degrees).
It hurts the eyes.
Burns and ignites
various materials.
Causes fires on large
distances from the epicenter.
Protection - opaque
materials, any obstruction,
creating a shadow.
penetrating radiation.
Flux of gamma rays and neutrons. Lasts 1025 seconds.Nuclear reactions are the source
flowing in the ammunition at the moment
explosion.
The damaging factors of penetrating radiation.
Passing through living tissue, gamma radiation and neutrons ionizeatoms and molecules of cells
resulting in violation
biological functions of cells
organs and the body as a whole
leads to radiation
illness.
Protection is shelter.
Reducing the intensity of penetrating radiation.
Weaken twice.intensity of gamma rays:
steel 2.8 cm thick,
concrete - 10 cm, soil - 14 cm,
wood - 30 cm.
radioactive infection.
Source - nuclear fission productscharge and radioactive isotopes,
resulting
effects of neutrons on materials,
from which the nuclear
ammunition.
Greatest Danger in the first hours
after precipitation from
radioactive cloud that forms
radioactive trail.
The damaging factors of radioactive contamination.
area contamination,buildings, crops,
reservoirs, air.
Radiation development
illness.
Zone of radioactive contamination.
3 - zone of moderateinfections (level
radiation 8 rad/h)
2 - Danger zone
infection (240 rad/h)
1 - zone extremely
dangerous infection
(800 rad/h).
Radiation dose and radiation sickness.
The first degree is 100-200 rad.The second degree is 200-400 rad.
Third degree - 300-600 rad.
Fourth degree - over 600 rad.
Radiation sickness.
Accompanied by nausea and vomiting.General weakness.
Hemorrhages.
Hair loss.
Eye damage.
Ulcer formation.
Especially dangerous is the hidden (latent period)
illness.
neutron weapons. neutron munitions.
The basis is thermonuclearcharges that use
nuclear fission and fusion reactions.
The damaging effect is mainly for
powerful penetrating radiation
(up to 40% of fast neutrons).
Features of destruction by neutron weapons.
Area of affected areapenetrating radiation
exceeds the area of the zone
blast damage in
several times, leading to
more deaths.
Protection is the same as
nuclear explosions.
Means of collective protection.
Defense structures1.Refuge;
2. The simplest shelters:
a) cracks
b) trenches
Means of protection
respiratory organs
(gas mask, respirator,
anti-dust
cloth masks, cotton gauze bandages).
Means of protection
skin cover.
Description of the presentation on individual slides:
1 slide
Description of the slide:
2 slide
Description of the slide:
Learning objectives: 1. The history of the creation of nuclear weapons. 2. Types of nuclear explosions. 3. Damaging factors of a nuclear explosion. 4. Protection against damaging factors of a nuclear explosion.
3 slide
Description of the slide:
Questions to test knowledge on the topic: "Safety and protection of people from emergencies" 1. What is an emergency? a) a particularly complex social phenomenon b) a certain state of the natural environment c) the situation in a certain territory, which may entail human casualties, damage to health, significant material losses and violations of living conditions. 2. What are the two types of emergencies according to their origin? 3. Name four kinds of situations in which modern man? 4. Name the system created in Russia for the prevention and elimination of emergency situations: a) a system for monitoring and controlling the state of the environment; b) United state system prevention and liquidation of emergencies; c) a system of forces and means to eliminate the consequences of emergency situations. 5. RSChS has five levels: a) object; b) territorial; c) local; d) settlement; e) federal; f) production; g) regional; h) republican; i) regional.
4 slide
Description of the slide:
The history of the creation and development of nuclear weapons This conclusion was the impetus for the development of nuclear weapons. In 1896, the French physicist A. Becquerel discovered the phenomenon of radioactive radiation. It marked the beginning of the era of the study and use of nuclear energy. 1905 Albert Einstein published his special theory of relativity. A very small amount of matter is equivalent to a large amount of energy. 1938, as a result of experiments by German chemists Otto Hahn and Fritz Strassmann, they manage to break a uranium atom into two approximately equal parts by bombarding uranium with neutrons. British physicist Otto Robert Frisch explained how energy is released when the nucleus of an atom divides. In early 1939, the French physicist Joliot-Curie concluded that a chain reaction was possible that would lead to an explosion of monstrous destructive power and that uranium could become an energy source, like an ordinary explosive.
5 slide
Description of the slide:
On July 16, 1945, the world's first atomic bomb test, called Trinity, was carried out in New Mexico. On the morning of August 6, 1945, an American B-29 bomber dropped the Little Boy uranium atomic bomb on the Japanese city of Hiroshima. The power of the explosion was, according to various estimates, from 13 to 18 kilotons of TNT. On August 9, 1945, the Fat Man plutonium atomic bomb was dropped on the city of Nagasaki. Its power was much greater and amounted to 15-22 kt. This is due to a more advanced bomb design. The successful test of the first Soviet atomic bomb was carried out at 7:00 on August 29, 1949 at the constructed test site in the Semipalatinsk region of the Kazakh SSR. Bomb testing showed that the new weapon was ready for combat use. The creation of this weapon marked the beginning of a new stage in the use of wars and military art.
6 slide
Description of the slide:
NUCLEAR WEAPONS are explosive weapons of mass destruction based on the use of intranuclear energy.
7 slide
Description of the slide:
8 slide
Description of the slide:
The explosion power of nuclear weapons is usually measured in units of TNT equivalent. The TNT equivalent is the mass of trinitrotoluene that would provide an explosion equivalent in power to the explosion of a given nuclear weapon.
9 slide
Description of the slide:
Nuclear explosions can be carried out at different heights. Depending on the position of the center of a nuclear explosion relative to the surface of the earth (water), there are:
10 slide
Description of the slide:
Ground Produced on the surface of the earth or at such a height when the luminous area touches the ground. Used to destroy ground targets Underground Produced below ground level. Characterized by severe contamination of the area. Underwater Produced underwater. Light emission and penetrating radiation is practically absent. Causes severe radioactive contamination of water.
11 slide
Description of the slide:
Space It is used at an altitude of more than 65 km to destroy space targets High-altitude It is produced at altitudes from several hundred meters to several kilometers. There is practically no radioactive contamination of the area. Airborne It is used at an altitude of 10 to 65 km to destroy air targets.
12 slide
Description of the slide:
Nuclear explosion Light radiation Radioactive contamination of the area Shock wave Penetrating radiation Electromagnetic pulse Damaging factors of nuclear weapons
13 slide
Description of the slide:
A shock wave is an area of sharp compression of air, propagating in all directions from the center of the explosion at supersonic speed. The shock wave is the main damaging factor in a nuclear explosion and about 50% of its energy is spent on its formation. The front boundary of the compressed air layer is called the front of the air shock wave. And it is characterized by the magnitude of excess pressure. As you know, overpressure is the difference between the maximum pressure in the front of an air wave and normal atmospheric pressure in front of him. Overpressure is measured in Pascals (Pa).
14 slide
Description of the slide:
During a nuclear explosion, four zones of destruction are distinguished: ZONE OF COMPLETE DESTRUCTION The territory exposed to the shock wave of a nuclear explosion with an overpressure (on the outer border) of more than 50 kPa. All buildings and structures, as well as anti-radiation shelters and part of the shelters, are completely destroyed, solid blockages are formed, the utility and energy network is damaged.
15 slide
Description of the slide:
During a nuclear explosion, four zones of destruction are distinguished: ZONE OF STRONG DESTRUCTION The territory exposed to the shock wave of a nuclear explosion with excess pressure (on the outer border) from 50 to 30 kPa. Ground buildings and structures are severely damaged, local blockages are formed, continuous and massive fires occur.
16 slide
Description of the slide:
During a nuclear explosion, four zones of destruction are distinguished: ZONE OF MEDIUM DESTRUCTION The territory exposed to the shock wave of a nuclear explosion with excess pressure (on the outer border) from 30 to 20 kPa. Buildings and structures receive medium damage. Shelters and shelters of the basement type are preserved.
17 slide
Description of the slide:
During a nuclear explosion, four zones of destruction are distinguished: ZONE OF WEAK DAMAGE The territory exposed to the shock wave of a nuclear explosion with an overpressure (on the outer border) from 20 to 10 kPa. Buildings receive minor damage.
18 slide
Description of the slide:
Light radiation is a stream of radiant energy, including visible, ultraviolet and infrared rays. Its source is a luminous area formed by hot products of the explosion and hot air up to millions of degrees. Light radiation spreads almost instantly and, depending on the power of the nuclear explosion, the time of the fireball lasts 20-30 seconds. The light radiation of a nuclear explosion is very strong, it causes burns and temporary blindness. Depending on the severity of the lesion, burns are divided into four degrees: the first is redness, swelling and soreness of the skin; the second is the formation of bubbles; the third - necrosis of the skin and tissues; the fourth is charring of the skin.
19 slide
Description of the slide:
Penetrating radiation (ionizing radiation) is a stream of gamma rays and neutrons. It lasts for 10-15 seconds. Passing through living tissue, it causes its rapid destruction and death of a person from acute radiation sickness in the very near future after the explosion. To assess the impact of various types of ionizing radiation on a person (animal), two of their main characteristics must be taken into account: ionizing and penetrating abilities. Alpha radiation has a high ionizing but weak penetrating power. So, for example, even ordinary clothes protect a person from this type of radiation. However, getting alpha particles into the body with air, water and food is already very dangerous. Beta radiation is less ionizing than alpha radiation, but more penetrating. Here, for protection, you need to use any shelter. And finally, gamma and neutron radiation have a very high penetrating power. Alpha radiation is helium-4 nuclei and can be easily stopped with a sheet of paper. Beta radiation is a stream of electrons that an aluminum plate is enough to protect against. Gamma radiation has the ability to penetrate even denser materials.
20 slide
Description of the slide:
The damaging effect of penetrating radiation is characterized by the magnitude of the radiation dose, i.e., the amount of radioactive radiation energy absorbed by a unit mass of the irradiated medium. Distinguish: the exposure dose is measured in roentgens (R). characterizes the potential danger of exposure to ionizing radiation with a general and uniform exposure of the human body; the absorbed dose is measured in rads (rad). determines the effect of ionizing radiation on biological tissues of the body, having different atomic composition and density Depending on the dose of radiation, four degrees of radiation sickness are distinguished: total dose of radiation, rad degree of radiation sickness latent period duration 100-250 1 - mild 2-3 weeks (curable) 250-400 2 - average week (with active treatment, recovery after 1.5-2 months) 400-700 3 - severe for several hours (with a favorable outcome - recovery after 6-8 months) More than 700 4 - extremely severe no (lethal dose )
21 slide
Description of the slide:
Radioactive particles, falling from the cloud to the ground, form a zone of radioactive contamination, the so-called trace, which can extend for several hundred kilometers from the epicenter of the explosion. Radioactive contamination - contamination of the terrain, atmosphere, water and other objects with radioactive substances from the cloud of a nuclear explosion. Depending on the degree of infection and the danger of injuring people, the trace is divided into four zones: A - moderate (up to 400 rad.); B - strong (up to 1200 rad.); B - dangerous (up to 4000 rad.); G - extremely dangerous infection (up to 10,000 rad.).
Nuclear weapon
and its damaging factors
The presentation was made by: SIRMAY Yana Yurievna, teacher of life safety,
MBOU "Tomponskaya multidisciplinary gymnasium", 2014
Nuclear weapon
- What is a nuclear weapon
- Types of explosions.
- The damaging factors of a nuclear explosion.
- The focus of nuclear destruction
What is a nuclear weapon?
Nuclear weapons are weapons of mass destruction of explosive action, based on the use of intra-nuclear energy, instantly released as a result of a chain reaction during the fission of atomic nuclei of radioactive elements (uranium-235 or plutonium-239).
The power of a nuclear weapon is measured in TNT equivalent, i.e. mass of trinitrotoluene (TNT), the explosion energy of which is equivalent to the explosion energy of a given nuclear weapon and is measured in tons,
Atomic bomb explosion in Nagasaki 1945
Types of explosions
ground
Underground
Surface
Underwater
Air
high-altitude
Damaging factors of a nuclear explosion
shock wave
light emission
Electromagnetic
pulse
radiation
infection
Penetrating
radiation
Shock wave The main damaging factor of a nuclear explosion. This is an area of sharp compression of air, propagating in all directions from the center of the explosion at supersonic speed. The source of the air wave is the high pressure in the explosion area (billions of atmospheres) and the temperature reaching millions of degrees.
The hot gases formed during the explosion, rapidly expanding, transfer pressure to neighboring layers of air, compressing and heating them, and they, in turn, affect the next layers, etc. As a result, a high-pressure zone propagates in the air at supersonic speed in all directions from the center of the explosion.
So, during the explosion of a 20-kiloton nuclear weapon, the shock wave travels 1000 m in 2 seconds, 2000 m in 5 seconds, and 3000 m in 8 seconds. The front boundary of the wave is called the front of the shock wave.
Directly behind the front of the shock wave, strong air currents are formed, the speed of which reaches several hundred kilometers per hour. (Even at a distance of 10 km from the site of the explosion of a munition with a capacity of 1 Mt, the air speed is more than 110 km / h.)
The damaging effect of SW is characterized by the amount of excess pressure.
Excess pressure is the difference between the maximum pressure in the SW front and normal atmospheric pressure, measured in Pascals (PA, kPa).
To characterize the destruction of buildings and structures, four degrees of destruction were adopted: complete, strong, medium and weak.
- Complete destruction
- Strong destruction
- Medium destruction
- Weak destruction
The impact of the shock wave on people is characterized by light, medium, severe and extremely severe lesions.
- Light lesions occur at an excess pressure of 20–40 kPa. They are characterized by temporary hearing loss, slight contusions, dislocations, bruises.
- Moderate lesions occur at an overpressure of 40–60 kPa. They manifest themselves in concussions of the brain, damage to the organs of hearing, bleeding from the nose and ears, and dislocations of the limbs.
- Severe lesions are possible with excess pressure from 60 to 100 kPa. They are characterized by severe contusions of the whole organism, loss of consciousness, fractures; possible damage to internal organs.
- Extremely severe lesions occur at excess pressure over 100 kPa. People have injuries of internal organs, internal bleeding, concussion, severe fractures. These lesions are often fatal.
Shelters provide protection from shock waves. In open areas, the effect of the shock wave is reduced by various recesses and obstacles. It is recommended to lie on the ground with your head in the direction from the explosion, preferably in a recess or a fold in the terrain.
light emission
Light radiation is a stream of radiant energy, including the ultraviolet, visible and infrared regions of the spectrum.
It is formed by products of the explosion heated to a million degrees and hot air.
The duration depends on the power of the explosion and ranges from fractions of a second to 20-30 seconds.
The strength of the light radiation is such that it can cause skin burns, eye damage (up to
blindness). Radiation leads to massive fires and explosions.
Protection for a person can be any barriers that do not let light through.
penetrating radiation
ionizing radiation
The radiation that is generated
during radioactive decay, nuclear transformations and forms ions of various signs when interacting with the environment. Basically, it's a stream
elementary particles that are not visible and not felt by man. Any nuclear radiation interacting with various materials ionize them. The action lasts 10-15 seconds.
There are three types of ionizing radiation - alpha, beta, gamma radiation. Alpha radiation has a high ionizing but weak penetrating power. Beta radiation is less ionizing but more penetrating. Gamma and neutron radiation have a very high penetrating power.
Protection against penetrating radiation is provided by various shelters and materials that attenuate the radiation and neutron flux.
Pay attention to the difference in the protective potential in gamma and neutron radiation.
Radiation (radioactive)
area contamination
Among the damaging factors of a nuclear explosion, radioactive contamination occupies a special place, since it can affect not only the area adjacent to the site of the explosion, but also the area remote by tens and even hundreds of kilometers. At the same time, contamination can be created over large areas and for a long time, posing a danger to humans and animals. The fission products falling out of the explosion cloud are a mixture of about 80 isotopes of 35 chemical elements of the middle part of the Mendeleev Periodic Table of Elements (from zinc #30 to gadolinium #64).
Since a significant amount of soil and other substances are involved in a fireball during a ground explosion, when cooled, these particles fall out in the form of radioactive fallout. As the radioactive cloud moves, radioactive fallout occurs in its wake, and thus a radioactive trail remains on the earth. The density of contamination in the region of the explosion and along the trail of the radioactive cloud decreases with distance from the center of the explosion.
The radioactive trace, with the direction and speed of the wind not changing, has the shape of an elongated ellipse and is conditionally divided into four zones: moderate (A), strong (B), dangerous (C) and extremely dangerous (D) contamination.
Zones of radioactive contamination
Zone
Extremely
dangerous
infections
danger zone
infections
Strong zone
infections
Zone
moderate
infections
Nuclear explosions in the atmosphere and in higher layers lead to the formation of powerful electromagnetic fields with wavelengths from 1 to 1000 m or more. These fields, in view of their short-term existence, are usually called an electromagnetic pulse (EMP). The consequence of exposure to EMR is the burnout of individual elements of modern electronic and electrical equipment. The duration of the action is several tens of milliseconds.
Potentially poses a serious threat, disabling any equipment that DOES NOT HAVE A PROTECTIVE SCREEN.
Electromagnetic pulse (EMP)
The focus of nuclear destruction
This is the area directly affected by the damaging factors of a nuclear explosion.
The focus of a nuclear lesion is divided into:
Full zone
destruction
The zone of the strong
destruction
Medium zone
destruction
zone of the weak
destruction
destruction
Depending on the type of nuclear charge, one can distinguish:
Thermonuclear weapons, the main energy release of which occurs during a thermonuclear reaction - the synthesis of heavy elements from lighter ones, and a nuclear charge is used as a fuse for a thermonuclear reaction;
Neutron weapon - a low-power nuclear charge, supplemented by a mechanism that ensures the release of most of the explosion energy in the form of a stream of fast neutrons; its main damaging factor is neutron radiation and induced radioactivity.
Participants in the development of the first samples of thermonuclear weapons,
who later won the Nobel Prize
L.D. Landau I.E. Tamm N.N. Semenov
V.L.Ginzburg I.M.Frank L.V.Kantorovich A.A.Abrikosov
The first Soviet aviation thermonuclear atomic bomb.
Bomb body RDS-6S
Bomber TU-16 -
nuclear weapon carrier
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Slides captions:
Modern means of destruction and their damaging factors. Measures to protect the population. The presentation was prepared by the teacher of life safety Gorpenyuk S.V.
Checking homework: Principles of organization of civil defense and its purpose. Name the tasks of GO. How is civil defense managed? Who is the Head of Civil Defense at the school?
The first test of a nuclear weapon In 1896, the French physicist Antoine Becquerel discovered the phenomenon of radioactive radiation. On the territory of the United States, in Los Alamos, in the desert expanses of the state of New Mexico, in 1942, an American nuclear center was established. On July 16, 1945, at 5:29:45 local time, a bright flash lit up the sky over the plateau in the Jemez Mountains north of New Mexico. A characteristic cloud of radioactive dust, resembling a mushroom, rose to 30,000 feet. All that remains at the site of the explosion are fragments of green radioactive glass, which the sand has turned into. This was the beginning of the atomic era.
WMD Chemical weapons Nuclear weapons Biological weapons
NUCLEAR WEAPONS AND ITS DAMAGE FACTORS Subjects studied: Historical data. Nuclear weapon. characteristics of a nuclear explosion. Basic principles of protection against damaging factors of a nuclear explosion.
In the early 40s. XX century in the United States developed the physical principles for the implementation of a nuclear explosion. The first nuclear explosion was carried out in the USA on July 16, 1945. By the summer of 1945, the Americans managed to assemble two atomic bombs, called "Kid" and "Fat Man". The first bomb weighed 2722 kg and was loaded with enriched Uranium-235. "Fat Man" with a charge of Plutonium-239 with a capacity of more than 20 kt had a mass of 3175 kg. History of the creation of nuclear weapons
In the USSR, the first test of an atomic bomb was carried out in August 1949. at the Semipalatinsk test site with a capacity of 22 kt. In 1953, the USSR tested a hydrogen, or thermonuclear, bomb. The power of the new weapons was 20 times greater than the power of the bomb dropped on Hiroshima, although they were the same size. In the 60s of the XX century, nuclear weapons are being introduced into all branches of the USSR Armed Forces. In addition to the USSR and the USA, nuclear weapons appear: in England (1952), in France (1960), in China (1964). Later, nuclear weapons appeared in India, Pakistan, in North Korea, in Israel. History of the creation of nuclear weapons
NUCLEAR WEAPONS are explosive weapons of mass destruction based on the use of intranuclear energy.
The device of the atomic bomb The main elements of nuclear weapons are: body, automation system. The case is designed to accommodate a nuclear charge and an automation system, and also protects them from mechanical, and in some cases, from thermal effects. The automation system ensures the explosion of a nuclear charge at a given moment of time and excludes its accidental or premature operation. It includes: - a safety and arming system, - an emergency detonation system, - a charge detonation system, - a power source, - a detonation sensor system. The means of delivery of nuclear weapons can be ballistic missiles, cruise and anti-aircraft missiles, aviation. Nuclear munitions are used to equip air bombs, land mines, torpedoes, artillery shells (203.2 mm SG and 155 mm SG-USA). Various systems have been invented to detonate the atomic bomb. The simplest system is an injector-type weapon in which a projectile made of fissile material crashes, and the addressee forms a supercritical mass. Atomic bomb, fired by the United States at Hiroshima on August 6, 1945, had an injection-type detonator. And it had an energy equivalent of approximately 20 kilotons of TNT.
Atomic bomb device
Delivery vehicles for nuclear weapons
Nuclear explosion Light radiation Radioactive contamination of the area Shock wave Penetrating radiation Electromagnetic pulse Damaging factors of a nuclear explosion
(Air) shock wave - an area of strong pressure propagating from the epicenter of the explosion - the most powerful damaging factor. Causes destruction over a large area, can "flow" into basements, crevices, etc. Protection: shelter. The damaging factors of a nuclear explosion:
Its action lasts for several seconds. A shock wave travels a distance of 1 km in 2 s, 2 km in 5 s, and 3 km in 8 s. Shock wave injuries are caused by both the action of excess pressure and its propelling action (velocity pressure), due to the movement of air in the wave. personnel, weapons and military equipment, located in open areas, are affected mainly as a result of the propelling action of the shock wave, and large objects (buildings, etc.) are affected by the action of excess pressure.
2. Light emission: lasts for a few seconds and causes severe fires in the area and burns to people. Defense: Any obstruction that provides shade. The damaging factors of a nuclear explosion:
The light radiation of a nuclear explosion is visible, ultraviolet and infrared radiation, acting for several seconds. For personnel, it can cause skin burns, eye damage and temporary blindness. Burns occur from direct exposure to light radiation on open areas of the skin (primary burns), as well as from burning clothes, in fires (secondary burns). Depending on the severity of the lesion, burns are divided into four degrees: the first is redness, swelling and soreness of the skin; the second is the formation of bubbles; the third - necrosis of the skin and tissues; the fourth is charring of the skin.
Damaging factors of a nuclear explosion: 3 . Penetrating radiation - an intense flow of gamma particles and neutrons, lasting for 15-20 seconds. Passing through living tissue, it causes its rapid destruction and death of a person from acute radiation sickness in the very near future after the explosion. Protection: shelter or barrier (layer of soil, wood, concrete, etc.) Alpha radiation is a helium-4 nucleus and can be easily stopped with a sheet of paper. Beta radiation is a stream of electrons that an aluminum plate is enough to protect against. Gamma radiation has the ability to penetrate even denser materials.
The damaging effect of penetrating radiation is characterized by the magnitude of the radiation dose, i.e., the amount of radioactive radiation energy absorbed by a unit mass of the irradiated medium. Distinguish between exposure and absorbed dose. The exposure dose is measured in roentgens (R). One X-ray is such a dose of gamma radiation that creates about 2 billion ion pairs in 1 cm3 of air.
Reducing the damaging effect of penetrating radiation depending on the protective environment and material
4 . Radioactive contamination of the area: occurs in the wake of a moving radioactive cloud when precipitation and explosion products fall out of it in the form of small particles. Protection: personal protective equipment (PPE). The damaging factors of a nuclear explosion:
In the focus of radioactive contamination of the area, it is strictly prohibited:
5 . Electromagnetic pulse: occurs for a short period of time and can disable all enemy electronics (aircraft on-board computers, etc.) Damaging factors of a nuclear explosion:
On the morning of August 6, 1945, there was a clear, cloudless sky over Hiroshima. As before, the approach from the east of two American aircraft (one of them was called Enola Gay) at an altitude of 10-13 km did not cause alarm (because every day they appeared in the sky of Hiroshima). One of the planes dived and dropped something, and then both planes turned and flew away. The dropped object on a parachute slowly descended and suddenly exploded at an altitude of 600 m above the ground. It was the "Baby" bomb. On August 9, another bomb was dropped over the city of Nagasaki. The total loss of life and the scale of destruction from these bombings are characterized by the following figures: 300 thousand people died instantly from thermal radiation (temperature about 5000 degrees C) and a shock wave, another 200 thousand were injured, burned, irradiated. On an area of 12 sq. km, all buildings were completely destroyed. In Hiroshima alone, out of 90,000 buildings, 62,000 were destroyed. These bombings shocked the whole world. This event is believed to have started the race nuclear weapons and confrontation between the two political systems of that time at a new qualitative level.
Atomic bomb "Kid", Hiroshima Types of bombs: Atomic bomb "Fat Man", Nagasaki
Types of nuclear explosions
Ground explosion Air explosion High-altitude explosion Underground explosion Types of nuclear explosions
the main way to protect people and equipment from a shock wave is shelter in ditches, ravines, hollows, cellars, protective structures; any barrier that can create a shadow can protect from the direct action of light radiation. Weakens it and dusty (smoky) air, fog, rain, snowfall. shelters and anti-radiation shelters (PRS) almost completely protect a person from the effects of penetrating radiation.
Measures to protect against nuclear weapons
Measures to protect against nuclear weapons
Questions for consolidation: What is meant by the term "WMD"? When did nuclear weapons first appear and when were they used? Which countries now officially possess nuclear weapons?
Fill in the table "Nuclear weapons and their characteristics", based on the textbook data (pp. 47-58). Homework: Damaging factor Characteristic Duration of exposure after the moment of explosion Units of measurement Shock wave Light radiation Penetrating radiation Radioactive contamination Electromagnetic impulse
Law of the Russian Federation "On Civil Defense" of February 12, 1998 No. 28 (as amended by the Federal Law of October 9, 2002 No. 123-FZ, of June 19, 2004 No. 51-FZ, of August 22, 2004 No. 122-FZ). Law of the Russian Federation "On martial law" dated January 30, 2002 No. 1. Decree of the Government of the Russian Federation dated November 26, 2007 No. 804 "On approval of the regulation on civil defense in the Russian Federation." Decree of the Government of the Russian Federation of November 23, 1996 No. 1396 “On the reorganization of the headquarters of the Civil Defense and Emergency Situations into the management bodies of the Civil Defense and Emergency Situations”. Order of the Ministry of Emergency Situations of the Russian Federation dated December 23, 2005 No. 999 “On approval of the procedure for creating non-standard emergency rescue teams”. Guidelines on the creation, preparation, equipping of the NASF - M .: Ministry of Emergency Situations, 2005. Guidelines for local governments on the implementation of the Federal Law of October 6, 2003 No. 131-FZ "On general principles local self-government in the Russian Federation" in the field of civil defense, protection of the population and territories from emergencies, ensuring fire safety and safety of people in water bodies. Manual on the organization and conduct of civil defense in an urban area (city) and at an industrial facility of the national economy. Magazine " civil protection» No. 3-10 for 1998 Duties of officials of civil defense organizations. Textbook "OBZH. Grade 10 ", A.T. Smirnov and others. M," Enlightenment ", 2010. Thematic and lesson planning for life safety. Yu.P.Podolyan.10 class. http://himvoiska.narod.ru/bwphoto.html Literature, Internet resources.
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Definition
A nuclear weapon is a weapon of mass destruction of explosive action, based on the use of intranuclear energy released during chain reactions of fission of heavy nuclei of some isotopes of uranium and plutonium or during thermonuclear reactions of fusion of light nuclei of hydrogen isotopes (deuterium and tritium) into heavier ones, for example, nuclei of helium isotopes .
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A nuclear explosion is accompanied by the release of a huge amount of energy, therefore, in terms of destructive and damaging effect, it can exceed the explosions of the largest ammunition filled with conventional explosives by hundreds and thousands of times.
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Among modern means of armed struggle, nuclear weapons occupy a special place - they are the main means of defeating the enemy. Nuclear weapons make it possible to destroy the means of mass destruction of the enemy, inflict heavy losses on him in manpower and military equipment in a short time, destroy structures and other objects, contaminate the area with radioactive substances, and also exert a strong moral and psychological impact on the personnel and thereby create a side, using nuclear weapons, favorable conditions for achieving victory in the war.
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Sometimes, depending on the type of charge, narrower concepts are used, for example: atomic weapons (devices that use fission chain reactions), thermonuclear weapons. Features of the destructive effect of a nuclear explosion in relation to personnel and military equipment depend not only on the power of the ammunition and the type of explosion, but also on the type of nuclear charger.
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Devices designed to carry out the explosive process of releasing intranuclear energy are called nuclear charges. The power of nuclear weapons is usually characterized by the equivalent of TNT, i.e. so much TNT in tons, the explosion of which releases the same amount of energy as the explosion of a given nuclear weapon. Nuclear weapons are conditionally divided by power into: ultra-small (up to 1 kt), small (1-10 kt), medium (10-100 kt), large (100 kt - 1 Mt), extra-large (over 1 Mt).
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Types of nuclear explosions and their damaging factors
Depending on the tasks solved with the use of nuclear weapons, nuclear explosions can be carried out: in the air, on the surface of the earth and water, underground and water. In accordance with this, explosions are distinguished: air, ground (surface), underground (underwater).
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Air nuclear explosion
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An air nuclear explosion is an explosion produced at an altitude of up to 10 km, when the luminous area does not touch the ground (water). Air explosions are divided into low and high. Strong radioactive contamination of the area is formed only near the epicenters of low air explosions. Infection of the area along the trail of the cloud does not have a significant impact on the actions of personnel.
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The main damaging factors of an air nuclear explosion are: an air shock wave, penetrating radiation, light radiation, and an electromagnetic pulse. During an air nuclear explosion, the soil swells in the area of the epicenter. Radioactive contamination of the area, affecting fighting troops, is formed only from low air nuclear explosions. In areas of application of neutron munitions, induced activity is formed in the soil, equipment and structures, which can cause damage (irradiation) to personnel.
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An air nuclear explosion begins with a short blinding flash, the light from which can be observed at a distance of several tens and hundreds of kilometers. Following the flash, a luminous area appears in the form of a sphere or hemisphere (with a ground explosion), which is a source of powerful light radiation. At the same time, a powerful flux of gamma radiation and neutrons propagates from the explosion zone into the environment, which are formed during a nuclear chain reaction and during the decay of radioactive fragments of nuclear charge fission. Gamma rays and neutrons emitted in a nuclear explosion are called penetrating radiation. Under the action of instantaneous gamma radiation, the atoms of the environment are ionized, which leads to the appearance of electric and magnetic fields. These fields, due to their short duration of action, are commonly called the electromagnetic pulse of a nuclear explosion.
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At the center of a nuclear explosion, the temperature instantly rises to several million degrees, as a result of which the substance of the charge turns into a high-temperature plasma that emits X-rays. The pressure of gaseous products initially reaches several billion atmospheres. The sphere of incandescent gases of the glowing area, seeking to expand, compresses the adjacent layers of air, creates a sharp pressure drop at the boundary of the compressed layer and forms a shock wave that propagates from the center of the explosion in various directions. Since the density of the gases that make up the fireball is much lower than the density of the surrounding air, the ball rises rapidly. In this case, a mushroom-shaped cloud is formed, containing gases, water vapor, small particles of soil and a huge amount of radioactive explosion products. Upon reaching the maximum height, the cloud is transported over long distances under the influence of air currents, dissipates, and radioactive products fall to the earth's surface, creating radioactive contamination of the area and objects.
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Ground (surface) nuclear explosion
This is an explosion produced on the surface of the earth (water), in which the luminous area touches the surface of the earth (water), and the dust (water) column from the moment of formation is connected to the explosion cloud. A characteristic feature of a ground (surface) nuclear explosion is a strong radioactive contamination of the terrain (water) both in the area of the explosion and in the direction of the explosion cloud.
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The damaging factors of this explosion are: air shock wave, light radiation, penetrating radiation, electromagnetic impulse, radioactive contamination of the area, seismic explosive waves in the ground.
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During ground-based nuclear explosions, an explosion crater and a strong radioactive contamination of the area are formed on the surface of the earth both in the area of the explosion and in the wake of the radioactive cloud. During ground and low air nuclear explosions, seismic explosive waves arise in the ground, which can disable buried structures.
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Underground (underwater) nuclear explosion
Underground nuclear explosion with soil ejection
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Underground nuclear explosion
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This is an explosion produced underground (under water) and characterized by the release of a large number soil (water) mixed with nuclear products explosive(fragments of fission of uranium-235 or plutonium-239). The damaging and destructive effect of an underground nuclear explosion is determined mainly by seismic explosive waves (the main damaging factor), the formation of a funnel in the ground and strong radioactive contamination of the area. Light emission and penetrating radiation are absent. Characteristic of an underwater explosion is the formation of a sultan (column of water), the basic wave formed during the collapse of the sultan (column of water).
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The main damaging factors of an underground explosion are: seismic explosive waves in the ground, air shock wave, radioactive contamination of the terrain and atmosphere. Seismic blast waves are the main damaging factor in a comflet explosion.
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Surface nuclear explosion
A surface nuclear explosion is an explosion carried out on the surface of the water (contact) or at such a height from it when the luminous area of the explosion touches the surface of the water. The main damaging factors of a surface explosion are: air shock wave, underwater shock wave, light radiation, penetrating radiation, electromagnetic pulse, radioactive contamination of the water area and coastal zone.
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Underwater nuclear explosion
An underwater nuclear explosion is an explosion produced in water at a certain depth.
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The main damaging factors of an underwater explosion are: an underwater shock wave (tsunami), an air shock wave, radioactive contamination of the water area, coastal areas and coastal facilities. During underwater nuclear explosions, the ejected soil can block the riverbed and cause flooding of large areas.
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high altitude nuclear explosion
A high-altitude nuclear explosion is an explosion produced above the boundary of the Earth's troposphere (above 10 km). The main damaging factors of high-altitude explosions are: air shock wave (at an altitude of up to 30 km), penetrating radiation, light radiation (at an altitude of up to 60 km), X-ray radiation, gas flow (exploding products of an explosion), electromagnetic pulse, atmospheric ionization (at an altitude of over 60 km).
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Stratospheric nuclear explosion
High-altitude nuclear explosions are subdivided into: stratospheric - explosions at altitudes from 10 to 80 km, space - explosions at altitudes of more than 80 km.
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The damaging factors of stratospheric explosions are: x-ray radiation, penetrating radiation, air shock wave, light radiation, gas flow, ionization of the environment, electromagnetic pulse, radioactive contamination of the air.
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space nuclear explosion
Space explosions differ from stratospheric ones not only in the values of the characteristics of the accompanying physical processes, but also in the physical processes themselves. The damaging factors of cosmic nuclear explosions are: penetrating radiation; x-ray radiation; ionization of the atmosphere, due to which a luminescent glow of the air occurs, lasting for hours; gas flow; electromagnetic impulse; weak radioactive contamination of the air.
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Damaging factors of a nuclear explosion
The main damaging factors and the distribution of the share of the energy of a nuclear explosion: shock wave - 35%; light radiation - 35%; penetrating radiation - 5%; radioactive contamination -6%. electromagnetic pulse -1% Simultaneous exposure to several damaging factors leads to combined damage to personnel. Armament, equipment and fortifications fail mainly from the impact of the shock wave.
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shock wave
A shock wave (SW) is a region of sharply compressed air propagating in all directions from the center of the explosion at supersonic speed. Hot vapors and gases, trying to expand, produce a sharp blow to the surrounding layers of air, compress them to high pressures and densities and heat up to high temperature(several tens of thousands of degrees). This layer of compressed air represents the shock wave. The front boundary of the compressed air layer is called the front of the shock wave. The SW front is followed by an area of rarefaction, where the pressure is below atmospheric. Near the center of the explosion, the velocity of SW propagation is several times higher than the speed of sound. As the distance from the explosion increases, the wave propagation speed decreases rapidly. At large distances, its speed approaches the speed of sound in air.
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The shock wave of an ammunition of medium power passes: the first kilometer in 1.4 s; the second - for 4 s; fifth - in 12 s. The damaging effect of hydrocarbons on people, equipment, buildings and structures is characterized by: velocity pressure; overpressure in the shock front and the time of its impact on the object (compression phase).
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The impact of HC on people can be direct and indirect. With direct exposure, the cause of injury is an instantaneous increase in air pressure, which is perceived as a sharp blow leading to fractures, damage to internal organs, and rupture of blood vessels. With indirect impact, people are amazed by flying debris of buildings and structures, stones, trees, broken glass and other objects. Indirect impact reaches 80% of all lesions.
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With an overpressure of 20-40 kPa (0.2-0.4 kgf / cm2), unprotected people can get light injuries (light bruises and concussions). The impact of SW with excess pressure of 40-60 kPa leads to lesions of moderate severity: loss of consciousness, damage to the hearing organs, severe dislocations of the limbs, damage to internal organs. Extremely severe lesions, often fatal, are observed at excess pressure over 100 kPa.
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The degree of damage by a shock wave to various objects depends on the power and type of explosion, the mechanical strength (stability of the object), as well as on the distance at which the explosion occurred, the terrain and the position of objects on the ground. To protect against the impact of hydrocarbons, one should use: trenches, cracks and trenches, which reduce its effect by 1.5-2 times; dugouts - 2-3 times; shelters - 3-5 times; basements of houses (buildings); terrain (forest, ravines, hollows, etc.).
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light emission
Light radiation is a stream of radiant energy, including ultraviolet, visible and infrared rays. Its source is a luminous area formed by hot explosion products and hot air. Light radiation propagates almost instantly and lasts, depending on the power of a nuclear explosion, up to 20 s. However, its strength is such that, despite its short duration, it can cause skin (skin) burns, damage (permanent or temporary) to the organs of vision of people, and ignition of combustible materials of objects. At the moment of formation of a luminous region, the temperature on its surface reaches tens of thousands of degrees. The main damaging factor of light radiation is a light pulse.
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Light pulse - the amount of energy in calories falling per unit area of the surface perpendicular to the direction of radiation, for the entire duration of the glow. The weakening of light radiation is possible due to its shielding by atmospheric clouds, uneven terrain, vegetation and local objects, snowfall or smoke. So, a thick layer attenuates the light pulse by A-9 times, a rare one - by 2-4 times, and smoke (aerosol) screens - by 10 times.
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To protect the population from light radiation, it is necessary to use protective structures, basements of houses and buildings, and the protective properties of the terrain. Any obstruction capable of creating a shadow protects against the direct action of light radiation and eliminates burns.
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penetrating radiation
Penetrating radiation - a stream of gamma rays and neutrons emitted from the zone of a nuclear explosion. The time of its action is 10-15 s, the range is 2-3 km from the center of the explosion. In conventional nuclear explosions, neutrons make up approximately 30%, in the explosion of neutron ammunition - 70-80% of the Y-radiation. The damaging effect of penetrating radiation is based on the ionization of cells (molecules) of a living organism, leading to death. Neutrons, in addition, interact with the nuclei of atoms of certain materials and can cause induced activity in metals and technology.
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Y radiation - photon radiation (with a photon energy of 1015-1012 J) that occurs when the energy state of atomic nuclei changes, nuclear transformations or particle annihilation.
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Gamma radiation is photons, i.e. electromagnetic wave carrying energy. In the air, it can travel long distances, gradually losing energy as a result of collisions with the atoms of the medium. Intense gamma radiation, if not protected from it, can damage not only the skin, but also internal tissues. Dense and heavy materials such as iron and lead are excellent barriers to gamma radiation.
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The main parameter characterizing penetrating radiation is: for y-radiation - the dose and dose rate of radiation, for neutrons - the flux and flux density. Permissible public exposure doses in war time: single - within 4 days 50 R; multiple - within 10-30 days 100 R; during the quarter - 200 R; during the year - 300 R.
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As a result of the passage of radiation through the materials of the environment, the intensity of the radiation decreases. The weakening effect is usually characterized by a layer of half attenuation, i.e. with. such a thickness of the material, passing through which the radiation is reduced by 2 times. For example, the intensity of y-rays is weakened by 2 times: steel 2.8 cm thick, concrete - 10 cm, soil - 14 cm, wood - 30 cm. up to 5000 times. A pound layer of 1.5 m protects almost completely from penetrating radiation.
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Radioactive contamination (contamination)
Radioactive contamination of the air, terrain, water area and objects located on them occurs as a result of the fallout of radioactive substances (RS) from the cloud of a nuclear explosion. At a temperature of about 1700 ° C, the glow of the luminous region of a nuclear explosion stops and it turns into a dark cloud, to which a dust column rises (therefore, the cloud has a mushroom shape). This cloud moves in the direction of the wind, and RVs fall out of it.
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The sources of radioactive substances in the cloud are the fission products of nuclear fuel (uranium, plutonium), the unreacted part of the nuclear fuel and radioactive isotopes formed as a result of the action of neutrons on the ground (induced activity). These RVs, being on contaminated objects, decay, emitting ionizing radiation, which in fact are the damaging factor. The parameters of radioactive contamination are: radiation dose (according to the impact on people), radiation dose rate - radiation level (according to the degree of contamination of the area and various objects). These parameters are a quantitative characteristic of damaging factors: radioactive contamination during an accident with the release of radioactive substances, as well as radioactive contamination and penetrating radiation during a nuclear explosion.
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Scheme of radioactive contamination of the area in the area of a nuclear explosion and in the wake of the movement of the cloud
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Radiation levels at the outer boundaries of these zones 1 hour after the explosion are 8, 80, 240, 800 rad/h, respectively. Most of the radioactive fallout, causing radioactive contamination of the area, falls out of the cloud 10-20 hours after a nuclear explosion.
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electromagnetic pulse
An electromagnetic pulse (EMP) is a combination of electric and magnetic fields resulting from the ionization of the atoms of the medium under the influence of gamma radiation. Its duration is a few milliseconds. The main parameters of EMR are the currents and voltages induced in wires and cable lines, which can lead to damage and disable electronic equipment, and sometimes to damage to people working with the equipment.
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During ground and air explosions, the damaging effect of an electromagnetic pulse is observed at a distance of several kilometers from the center of a nuclear explosion. The most effective protection against an electromagnetic pulse is the shielding of power supply and control lines, as well as radio and electrical equipment.
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The situation that develops during the use of nuclear weapons in the centers of destruction.
The focus of nuclear destruction is the territory within which, as a result of the use of nuclear weapons, mass destruction and death of people, farm animals and plants, destruction and damage to buildings and structures, utility and energy and technological networks and lines, transport communications and other objects occurred.
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Zones of the focus of a nuclear explosion
To determine the nature of possible destruction, the volume and conditions for conducting rescue and other urgent work, the nuclear lesion site is conditionally divided into four zones: complete, strong, medium, weak destruction.
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Zone of complete destruction
The zone of complete destruction has an overpressure at the front of the shock wave of 50 kPa at the border and is characterized by: massive irretrievable losses among the unprotected population (up to 100%), complete destruction of buildings and structures, destruction and damage to utility and energy and technological networks and lines, as well as parts shelters of civil defense, the formation of solid blockages in settlements. The forest is completely destroyed.
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Zone of severe damage
The zone of severe destruction with excess pressure at the shock wave front from 30 to 50 kPa is characterized by: massive irretrievable losses (up to 90%) among the unprotected population, complete and severe destruction of buildings and structures, damage to public utilities and technological networks and lines, the formation of local and solid blockages in settlements and forests, the preservation of shelters and most anti-radiation shelters of the basement type.
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Medium damage zone
Zone of medium destruction with overpressure from 20 to 30 kPa. It is characterized by: irretrievable losses among the population (up to 20%), medium and severe destruction of buildings and structures, the formation of local and focal blockages, continuous fires, the preservation of utility networks, shelters and most of the anti-radiation shelters.
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Zone of weak damage
The zone of weak destruction with excess pressure from 10 to 20 kPa is characterized by weak and medium destruction of buildings and structures. The focus of the lesion but the number of dead and injured can be commensurate with or exceed the lesion in an earthquake. So, during the bombing (bomb power up to 20 kt) of the city of Hiroshima on August 6, 1945, his most of(60%) was destroyed, and the death toll amounted to 140,000 people.
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Exposure to ionizing radiation
The personnel of economic facilities and the population entering the zones of radioactive contamination are exposed to ionizing radiation, which causes radiation sickness. The severity of the disease depends on the dose of radiation (irradiation) received. The dependence of the degree of radiation sickness on the magnitude of the radiation dose is shown in the table on the next slide.
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Dependence of the degree of radiation sickness on the magnitude of the radiation dose
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Under the conditions of hostilities with the use of nuclear weapons, vast territories may turn out to be in the zones of radioactive contamination, and exposure of people may take on a mass character. In order to exclude overexposure of the personnel of facilities and the population in such conditions and to increase the stability of the functioning of national economy facilities under conditions of radioactive contamination in wartime, permissible exposure doses are established. They are: with a single irradiation (up to 4 days) - 50 rad; repeated irradiation: a) up to 30 days - 100 rad; b) 90 days - 200 rad; systematic exposure (during the year) 300 rad.
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Rad (rad, abbreviated from English radiationabsorbeddose - absorbed dose of radiation), off-system unit of absorbed dose of radiation; it is applicable to any kind of ionizing radiation and corresponds to a radiation energy of 100 erg absorbed by an irradiated substance weighing 1 g. 1 rad = 2.388×10-6 cal/g = 0.01 j/kg.
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SIEVERT (sievert) - a unit of equivalent dose of radiation in the SI system, equal to the equivalent dose if the dose of absorbed ionizing radiation, multiplied by a conditional dimensionless factor, is 1 J / kg. Since different types of radiation cause different effects on biological tissue, a weighted absorbed dose of radiation, also called the equivalent dose, is used; it is obtained by modifying the absorbed dose by multiplying it by the conventional dimensionless factor adopted by the International Commission on X-Ray Protection. At present, the sievert is increasingly replacing the physical equivalent of the roentgen (FER), which is becoming obsolete.
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Radioactivity: alpha, beta, gamma radiation
The word "radiation" comes from the Latin radius and means a beam. In principle, radiation is all types of radiation existing in nature - radio waves, visible light, ultraviolet, and so on.
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