According to whether it is charged or not is divided into charged particles (α particles, β particles, protons, etc.) and uncharged particles (X-rays, γ-rays, neutrons, etc.).
1. α-rays
are composed of helium nuclei (also known as α particles) moving at high speed. With 2 units of positive charge, the mass number is 4, its ionization effect is large, through the ability to small. 10cm of air, a thin glass plate, surgical gloves, clothing, a piece of paper or biological tissues of the epidermis is enough to block the alpha particles. However, the ionization ability of alpha particles is particularly large, and once an alpha particle emitter is accidentally allowed to enter the human body, the harm caused by the large amount of ionization caused by internal irradiation of alpha particles is particularly large. The focus of protection is not to let the emitter of alpha particles into the body to avoid causing internal irradiation damage.
2. β-rays
are high-speed movement of the electron stream. It carries a unit charge and has a light mass. Its ionization effect is small, through the ability to larger. β particles can cause internal and external irradiation damage. For the protection of beta rays, materials with lower atomic number should be used. A few millimeters of aluminum, clothing or plexiglass can better protect against external exposure to β-rays.
3. γ-rays
γ-rays are photons, electrically uncharged, no static quality, is a very short wavelength electromagnetic waves, is electromagnetic radiation. Ionization effect is small, penetrating ability. Mainly caused by external radiation damage. Commonly used protective materials are water, brick, concrete, aluminum, iron,, copper, lead, tungsten, depleted uranium and so on.
4. Neutrons are uncharged particles with a mass of about one atomic mass unit. Neutron protection: use high hydrogen-containing water, plastics, paraffin, etc. to slow down fast neutrons; use lithium, boron, etc. to absorb slow neutrons; use high atomic number of materials to protect the neutron slowing and absorption of γ-rays generated during the process.
2. In daily life, what are the ionizing radiation that people are exposed to
People are exposed to natural radiation every moment, and this radiation includes cosmic rays, rays emitted by radioactive substances in soil, water, food and air. Radon, a radioactive noble gas found in nature, is the main source of natural radiation. The most common type of artificial radiation that people are exposed to is medical irradiation, such as X-ray radiography, CT examinations and radiation therapy.
The unit of radiation dose relevant to human health is commonly expressed in sieverts (Sv). The global average annual effective dose of individuals from natural radiation is about 2.4mSv (1Sv=1000mSv), of which 0.4mSv comes from cosmic rays, 0.5mSv comes from terrestrial γ-rays, 1.2mSv from inhalation (mainly radon), and 0.3mSv from ingestion. it can be seen that radon is the most important source of natural radiation. A small amount of radiation exposure will not jeopardize human health.
In daily life, the effective dose of a chest, oral cavity, limbs X-ray diagnosis is 0.01mSv; head and neck X-ray diagnosis is 0.1mSv; mammary gland and abdominal X-ray diagnosis, head CT scanning is 1mSv; abdominal CT, barium stomach meal, barium *** for 10mSv; travel by plane 2000 kilometers of about 0.01mSv; daily smoking 20
3. What is ionizing radiation
Ionizing radiation is a general term for all radiation that can cause material ionization, and there are many types of high-speed charged particles, alpha particles, beta particles, protons, uncharged particles, seeds, as well as X-rays, gamma rays.
Alpha rays are a charged particle stream, due to the charged, it is easy to cause ionization wherever it goes. alpha rays have a strong ionization ability, this property can be used.
It also brings a certain damage to the place, and has a greater ability to destroy the tissues in the human body. Due to its large mass, poor penetration ability, the range in the air is only and centimeter, as long as a piece of paper or healthy skin can block.
β-rays are also a high-speed charged particles, its ionization capability is much smaller than α-rays, but the penetration capability is larger than α-rays, but with X, γ-rays than β-rays have a shorter range, and can easily be absorbed by aluminum foil, plexiglass and other materials. X-rays and γ-rays are roughly the same nature, is not with the length of the electric wave electromagnetic waves, so they are collectively referred to as photons.
The two are extremely penetrating, and special attention should be paid to accidental exposure protection. Ionizing radiation exists in nature, but at present artificial radiation has spread to all areas, specializing in the production, use and research of ionizing radiation work, known as radiation workers.
Radiation-related occupations are: nuclear industrial system and raw material exploration, mining, smelting and refining, nuclear fuel and reactor production, use and research; agricultural irradiation to cultivate new varieties of vegetables and fruits, insurance, food storage; medical X-ray fluoroscopy, photographic diagnosis, radionuclide determination of the human body organs, radiation treatment of tumors, etc.; the industrial sector of a variety of gas pedals, ray generators and electron microscopes, electron microscopes, radiation treatment, and so on. The industrial sector of various accelerators, ray generators and electronic microscopes, electronic speed welding machine, color television tubes, high-voltage tubes and so on.
4. Ionizing radiation is harmful to people
The human body is irradiated by the dose exceeds a certain limit, it can occur harmful effects. Under the action of electric radiation, the body's reaction depends on the type of ionizing radiation, dose, exposure conditions and sensitivity of the body.
Ionizing radiation can cause radiculopathy, which is a systemic reaction of the body, almost all organs and systems are pathologically altered, but among them, the nervous system, hematopoietic organs and digestive system are the most obvious changes.
Ionizing radiation damage to the body can be divided into acute radiation damage and chronic radiation damage. A short period of time to receive a certain dose of irradiation, can cause acute damage to the body, usually seen in nuclear accidents and radiation therapy patients.
And a longer period of time dispersed to accept a certain dose of irradiation, can cause chronic radioactive damage, such as skin damage, hematopoietic disorders, leukopenia, impaired fertility and so on. In addition, excessive radiation can also cause cancer and cause fetal death and malformation.
The annual average effective dose for 5 consecutive years as determined by the regulatory authority (but no retrospective averaging is allowed) is 20 mSv; the effective dose in any one year is 50 mSv; the annual equivalent dose to the crystalline lens of the eye is 150 mSv; and the annual equivalent dose to the limbs (hands and feet) or the skin is 500 mSv.
For those aged 16-18 who have received employment training that involves radiation exposure and apprenticeships and workers aged 16-18 who have received employment training that involves radiation exposure, they are entitled to a maximum of 5 years of radiation exposure, including a maximum of 10 years of radiation exposure. Expanded Information:
For apprentices aged 16 to 18 years who receive training for employment involving radiation exposure and for students aged 16 to 18 years who are required to use radioactive sources in the course of their studies, occupational exposure shall be controlled so that it does not exceed the following limits: annual effective dose, 6 mSv; annual equivalent dose to the crystalline lens of the eye, 50 mSv; and annual equivalent dose to the limbs (hands and feet) or the skin, 150 mSv.
Everyday Protection Against Ionizing Radiation:
Devices and sources of radiation that can produce radiation are strictly regulated. Radiation projects must be pre-evaluation of occupational hazards of radiation projects and evaluation of the effectiveness of control before they can be put into use.
Workplaces where radiation is present are tested annually to ensure the safety of radiation workers and the public. No matter where you are, see a sign of ionizing radiation, keep away, please do not approach, and at the same time more do not just barge in. Hospitals to do related radiological examination, family members in the case of necessity before accompanying the entry.
Hospitals are equipped with relevant protective equipment, according to different tests, under the guidance of the doctor, wear the appropriate protective equipment, pay attention to glasses, thyroid, gonads to strengthen the protection. The first thing you need to do is to get your hands on a pair of shoes or boots, and you'll be able to get them on the back of your head and on the back of your neck.
Search Dog Encyclopedia - Ionizing Radiation
5. Nuclear Radiation Protection Knowledge
Personal Radiation Protection Knowledge 1. In the event of a nuclear and radiological emergency, the first thing the public must do is to obtain as much credible information as possible about the emergency, and to understand the decisions and notifications of the *** authorities.
The public should keep in touch with the local *** through various means, and remember not to believe rumors or gossip. The second thing is to quickly take the necessary precautions to protect yourself.
For example, you can choose the nearest building to hide, you should close the doors and windows, turn off the ventilation equipment. According to the local *** arrangements for the implementation of organized and orderly evacuation.
When a radioactive dispersal event is judged to have occurred, remember not to face the wind nor run with the wind, should try to hide to the side of the wind, and quickly enter the building to hide. Take respiratory protection, including covering the mouth and nose with a wet towel, cloth, etc., to filter radioactive particles.
If radioactive contamination of body surfaces is suspected, use bathing and changing clothes to minimize radioactive contamination. Prevent ingestion of contaminated food or water.
In the event of a nuclear and radiological emergency, the public should pay special attention to maintaining a stable state of mind and should not be alarmed. 2. What are the early protective measures for nuclear and radiation emergencies? Early refers to the occurrence of nuclear and radiation emergencies within 1 to 2 days after the occurrence of protective measures that can be used on the personnel are: concealment, respiratory protection, taking stable iodine, evacuation, control of import and export access, and so on.
Among them, respiratory protection is the action of covering the nose with a dry or wet towel, which can prevent or reduce the inhalation of radionuclides. Taking stabilized iodine prevents or reduces the deposition of radioactive iodine in the smoke plume in the thyroid gland after it enters the body.
3. What are the protective measures for the middle stage of a nuclear and radiological emergency? During the mid-incident phase, a significant amount of radioactive material has been deposited on the ground. At this point, early protective measures can be continued for individuals, except that discontinuation of respiratory protection may be considered.
To avoid excessive cumulative doses from prolonged stays, the competent authorities may take the form of controlled and planned relocation of populations from the contaminated area to the outside. Restrictions on the sale and consumption of locally produced or stored food and drinking water should also be considered.
According to the characteristics of the irradiation pathway for personnel in this period, protective measures can also be taken: the use of stored feed in animal husbandry, decontamination of the body surface of the personnel, and rescue of the sick and wounded. 4. What are the protective measures for a nuclear and radiation emergency? In the late stage of an accident (recovery period) the question is: if and when can society resume normal life? Or is there a need for further protective measures? At the late stage of the incident, the main exposure pathway is internal exposure due to ingestion of contaminated food and inhalation of resuspended material.
Therefore, protective measures that can be taken include control of ingress and egress pathways, avoidance of relocation, control of food and water, use of stored feeds, and decontamination of the area. 5. Under what circumstances should sheltering measures be taken and what should the public be aware of? Concealment is one of the main protective measures in the early and middle stages of an emergency where large amounts of radioactive material are released into the atmosphere.
Most buildings can reduce the inhalation dose to people inside the building by about half. After a period of concealment and passage of the plume, the concentration of radionuclides in the air within the concealed body will rise, at which point ventilation is necessary to reduce the airborne concentration of radioactivity to a level equivalent to that of a cleaner outdoor area.
Consequently, sheltering is less effective protection against a sustained release. The duration of concealment is generally considered to be no more than 2 days.
6. When are personal protective measures required and what should the public be aware of? When the air is contaminated with radioactive material, some personal protective measures are needed. Covering the mouth and nose with a handkerchief, towel, cloth, etc. can reduce the dose due to inhalation of radioactive material by about 90%.
Body surface protection can be provided by a variety of everyday clothing, including hats, bandanas, raincoats, gloves, and boots. Decontamination of persons who have been or are suspected of having been contaminated by radioactivity on the body surface is as simple as telling the person concerned to shower with water and to remove and store contaminated clothing, shoes, hats, etc., until there is time to monitor or treat them at a later date.
To prevent the spread of radioactive contamination to uncontaminated areas. 7. What is the case for taking stabilized iodine? After a nuclear and radiological emergency, it is possible for a person to ingest radioactive iodine and concentrate it in the thyroid gland, exposing this organ to a larger dose.
Stabilized iodine can reduce the amount of radioactive iodine absorbed by the thyroid gland. If you take stabilized iodine while inhaling radioactive iodine, you can block 90% of the radioactive iodine deposition in the thyroid.
Taking stabilized iodine within a few hours of inhaling radioactive iodine still reduces the amount of radioactive iodine absorbed by the thyroid by about half. The recommended dosage for adults is 100 milligrams of iodine, for pregnant women and children 3 to 12 years of age, 50 milligrams, and for children under 3 years of age, 25 milligrams.
8. What should I be aware of when taking stabilized iodine? For newborns within the first month of life, the amount of stabilized iodine taken should be kept to the lowest level that is effective. Stabilized iodine should be used with caution or not used in some individuals, such as those with nodules in the thyroid gland, those who have been cured of goiter, those who have been treated with radioactive iodine, those with chronic inflammatory diseases of the thyroid gland, those who have had unilateral removal of the thyroid gland, those who have subclinical hypothyroidism, those who are allergic to iodine, and those who have certain skin disorders (acne, eczema, psoriasis).
9. Can iodine tablets (KI) protect against radiation? How does it protect against radiation? Physiologically, the main source of iodine in the human body is the uptake by the thyroid gland, which relies on iodine for the production of thyroid hormones. ki is a stabilized iodine, which saturates the iodine in the thyroid gland and thus prevents the uptake of radioactive iodine.
The Chernobyl experience has shown that radioactive iodine was a major factor in the impact of the Chernobyl accident, which resulted in more than 5,000 cases of thyroid cancer in children, all of whom were between the ages of 0 and 18. Therefore, the primary targets for KI distribution are young children and pregnant women.
Iodine tablets do not protect against radioactivity from outside the body and radioactivity other than iodine that is absorbed by the body. This is why iodine thyroid blockade will be used in most settings in combination with other protective measures (e.g., staying concealed indoors, closing doors and windows, etc.).
In order to take full advantage of the effects of iodine stabilization on iodothyroid blockade, iodine stabilization tablets need to be taken before or as soon as possible after exposure. Even a few hours after the accident, the uptake of 50% iodine by the thyroid gland can still be blocked by administration.
To prevent inhalation of radioactive iodine isotopes, a single tablet dose of stabilized iodine is usually sufficient, and it can act 24 small.
6. What is called ionizing radiation
Ionizing radiation is a general term for all radiation that can cause material ionization, and there are many types of it, high-speed charged particles have alpha particles, beta particles, protons, uncharged particles have neutrons, and X-rays, gamma rays.
Alpha rays are a charged particle stream, due to the charged, it is easy to cause ionization wherever it goes. alpha rays have a strong ionization ability, this nature can be used. It also brings certain damage to the place, and has a greater ability to destroy the tissues in the human body. Due to its large mass, poor penetration ability, the range in the air is only and centimeter, as long as a piece of paper or healthy skin can block.
β-rays are also a high-speed charged particles, its ionization capability is much smaller than α-rays, but the penetration capability is larger than α-rays, but with X, γ-rays than β-rays have a shorter range, and can easily be absorbed by aluminum foil, plexiglass and other materials.
X-rays and γ-rays are roughly the same nature, is not with the length of the electric wave electromagnetic waves, so they are collectively referred to as photons. Both are extremely penetrating, and special attention should be paid to accidental exposure protection.
Ionizing radiation exists in nature, but now artificial radiation has been all over the field, specializing in the production, use and research of ionizing radiation work, known as radiation workers. Radiation-related occupations are: nuclear industrial system and raw material exploration, mining, smelting and refining, nuclear fuel and reactor production, use and research; agricultural irradiation cultivation of new varieties of vegetables and fruits, insurance, food storage; medical X-ray fluoroscopy, photographic diagnosis, radionuclide determination of the human body organs, radiation treatment of tumors, etc.; industrial sectors of the various gas pedals, radiation generators and Electronic microscope, electronic speed welding machine, color TV tube, high-voltage electronic tubes.
Natural radiation:
Humans mainly receive natural radiation from nature. It comes from the sun, cosmic rays and emissive nuclides present in the earth's crust. Radon spills from the ground are another important source of natural radiation. Cosmic rays from space include energized light quanta, electrons, gamma rays and X-rays. The main emissive nuclides found in the earth's crust are uranium, thorium and polonium, as well as other emissive substances. They emit alpha, beta, or gamma rays.
Artificial radiation:
Radiation is widely used in medicine, industry and other fields. Artificial radiation is used in medical equipment (e.g., medical and imaging equipment); in research and teaching facilities; and in nuclear reactors and their auxiliary facilities, such as uranium mines and nuclear fuel plants. Facilities such as these inevitably produce radioactive waste, some of which leaks doses of radiation into the environment. Radioactive materials are also widely used in everyday consumer products, such as glow-in-the-dark watches, glazed ceramics, artificial dentures, and smoke detectors.
Think about the occupation there are boilers and pressure vessels nondestructive testing, commonly used command source to γ source for the signal source, radiography machine to emit X-rays, the above two are commonly used in the nondestructive testing industry, and now also use the same time the magnetic particle and infiltration and ultrasound, but the ray machine and the γ source is also irreplaceable work necessary
7. Who can tell me the difference between electromagnetic radiation and ionizing radiation, and the radiation mediator associated with daily life. As well as daily life related to radiation medium
The difference between electromagnetic radiation and ionizing radiation:
First, the method of generation is different:
1, ionizing radiation is to make the electrons in the atoms or molecules of the material to become a free state, so that these atoms or molecules ionization phenomenon occurs in the energy of the radiation.
2. Electromagnetic radiation is produced by the movement of electric charge.
Second, the harm to people:
1, some electromagnetic radiation has a certain effect on the human body.
2, October 27, 2017, the World Health Organization's International Agency for Research on Cancer published a preliminary collation of the list of carcinogens reference, ionizing radiation (all types) in the list of class I carcinogens.
Expanded information:
Principles of protection:
1, Time protection:
Regardless of the type of exposure, the size of the cumulative dose of human exposure is directly proportional to the time of exposure. The longer the exposure time, the more serious the radiation hazard. Try to shorten the time of radioactive work, in order to achieve the purpose of reducing the dose of exposure.
2, distance protection:
The radiation dose rate at a certain place is inversely proportional to the square of the distance from the radioactive source, and the greater the distance from the radioactive source, the smaller the dose rate at that place. So try to work away from the radioactive source. To achieve the purpose of protection.
3, shielding protection:
It is to set up a protective barrier between the person and the radioactive source. Because the ray through the atomic number of material, will be absorbed a lot, so that part of the radiation dose to reach the human body is weakened. Commonly used shielding materials are lead, reinforced concrete, lead glass and so on.