First, the damage effect of four kinds of killing factors
(1) Damage caused by light radiation
Light radiation can cause skin and mucous membrane burns on the body surface, which are called direct burns or light radiation burns. Under the action of light radiation, buildings, fortifications, clothes, etc. cause human burns, which are called indirect burns or flame burns. The damage caused by light radiation mainly depends on the light pulse.
Main characteristics of light radiation burn:
1. Orientation of burn site: The linear propagation of light radiation makes burns often occur on the side facing the explosion center, so it is called lateral burn. The boundaries of burns are clear.
2. Shallow burn depth: Short illumination time determines shallow burn depth. Most of them are second-degree burns except for large-scale deep burns at close range. Even if third-degree burns occur, deep subcutaneous tissue is rarely involved. The depth of the wound is generally clear.
3. The incidence of burns in special parts is high.
(1) Face, ears, neck and hands are the most exposed parts of the body.
(2) Respiratory tract burn: Respiratory tract burn is an indirect burn. It is caused by hot air, dust, deposits, smoke and even flames inhaled into the combustion environment.
(3) Eye burns: Light radiation can cause burns on eyelids, cornea and fundus. Fundus burn, also called retinal burn, is a special kind of burn caused by light radiation. If people look directly at the fireball, the light pulse will increase by 103 ~ 104 times than the incident light through the focusing action of the eyes, forming a fireball image on the retina, causing burns. The boundary of retinal burn is 3 ~ 4 times larger than that of mild skin burn.
4. Flash blindness: After the strong light of nuclear explosion stimulates the eyes, rhodopsin, a photosensitive chemical on the retina, is "bleached and decomposed", thus causing temporary visual impairment, which is called flash blindness. After flash blindness, people will immediately have symptoms such as decreased vision, black eyes, "Venus" flying, abnormal color vision, swelling and pain. In severe cases, symptoms of autonomic nervous dysfunction such as headache, dizziness, nausea and vomiting occur, but the duration of symptoms is short, and they can recover spontaneously from a few seconds to 3 ~ 4 hours after explosion without any sequelae. The occurrence limit of flash blindness is far beyond fundus burns, which has a great influence on command, flight, driving and observation personnel.
(B) the role of shock wave damage
Shock wave injury, referred to as blast injury, is a variety of injuries caused by direct or indirect action of shock wave on human body.
1. Direct explosion injury
(1) Overpressure and negative pressure and direct action: Simple overpressure and negative pressure generally do not cause body surface damage, but mainly harm organs containing gas or liquid, such as heart, lung, gastrointestinal tract, bladder and auditory organs, and the connecting parts between tissues with different densities.
For example, after overpressure acts on the body surface, on the one hand, it squeezes the abdominal wall, making the abdominal pressure increase, and the venous blood of the upper and lower vena cava with diaphragm suddenly pours into the heart and lungs, and the cardiopulmonary blood volume suddenly increases; On the other hand, it compresses the chest wall, which reduces the volume of the chest cavity and increases the internal pressure of the chest cavity sharply. After overpressure, followed by negative pressure, the thoracic cavity and abdominal cavity expand. This rapid compression and expansion causes a series of drastic changes in hemodynamics in the chest cavity, thus causing damage to the heart, lungs and blood vessels.
(2) Throwing and dynamic pressure impact: After the human body is impacted by the shock wave, it gains acceleration, displaces or is thrown, and collides with the ground or other objects during moving and landing, causing various injuries. Such as liver and spleen rupture, soft tissue tear, craniocerebral injury, fracture, dislocation and even limb dispersion.
2. Indirect blast injury: due to the shock wave, various fortifications and buildings collapsed, resulting in a large number of high-speed flying objects, which indirectly caused various injuries to people, such as crushing injury, crushing injury, flying stone injury, glass sliding injury, silt blocking the upper respiratory tract, suffocation, etc.
3. Clinical characteristics of blast injury
(1) Multiple injuries, multiple injuries and complex injuries: Because many injury factors (such as overpressure and dynamic pressure, direct and indirect effects) act on the body almost at the same time, the types and complexity of blast injuries are determined. More than moderate blast injuries are often multiple injuries and multiple injuries. There are both direct and indirect injuries; There are both trauma and visceral injury; It may be a simple explosion injury, or it may be a combination of burns and radiation injuries.
(2) The exterior is light and the interior is heavy, which develops rapidly: especially the blast injury mainly caused by overpressure, the body surface is often not damaged or only slightly damaged, while the internal organs may be seriously damaged. Severe visceral injury, due to the rapid development of injury and unbalanced compensation, can quickly lead to shock and cardiopulmonary dysfunction, and even lead to the death of the wounded.
(3) Damage caused by early nuclear radiation
Early nuclear radiation is a unique killing factor of nuclear weapons. When the human body is exposed to a certain dose of radiation, it may cause acute radiation sickness, or it may have biological effects of low-dose external radiation.
(4) Damage caused by radioactive pollution
There are three ways for radioactive pollution to hurt people:
1. External radiation injury: When people stay in heavily polluted areas and receive γ -ray external radiation dose > > 1Gy, it can cause acute radiation sickness caused by external radiation. This is the main injury to personnel caused by falling ash.
2. Internal irradiation damage: Dust falls into the body through various channels, and when the radioactive nuclide in the body reaches a certain deposition amount, it can cause internal irradiation damage.
3. Beta-ray skin damage: The falling volcanic ash directly contacts the skin, and when the dose is greater than 5Gy, it can cause beta-ray skin damage.
People who stay in polluted areas for a long time without protection may be injured in three ways at the same time.