"0.05 - 0.2 Sv
No symptoms. Potential cancer and mutation of genetic material, according to the LNT model. This is disputed. (Note: see hormesis)
0.2 - 0.5 Sv
No noticeable symptoms. Number of erythrocytes decreases temporarily.
0.5 - 1 Sv
Mild radiation sickness with headache and increased risk of infection. Temporary male sterility is possible.
1 - 2 Sv
Light radiation poisoning, 10% fatality after 30 days (LD 10/30). Typical symptoms include mild to moderate nausea (50% probability at 200 rad), with occasional vomiting, beginning 3 to 6 hours after irradiation and lasting for up to one day. This is followed by a 10 to 14 day anastasis, after which light symptoms like general illness, anorexia and fatigue (50% probability at 200 rad). The immune system is depressed, with convalescence extended and increased risk of infection. Temporary male sterility is common.
2 - 3 Sv
Severe radiation poisoning, 35% fatality after 30 days (LD 35/30). Nausea is common (100% at 300 rad), with 50% risk of vomiting at 280 rad. Symptoms onset at 1 to 6 hours after irradiation and last for 1 to 2 days. After that, there is a 7 to 14 day anastasis, after which the following symptoms appear: loss of hair all over the body (50% probability at 300 rad), fatigue and general illness. There is a massive loss of leukocytes, greatly increasing the risk of infection. Permanent female sterility is possible. Convalescence takes one to several months.
3 - 4 Sv
Severe radiation poisoning, 50% fatality after 30 days (LD 50/30). As with 200 to 300 rad dosage, with uncontrollable bleeding in the mouth, under the skin and in the kidneys (50% probability at 400 rad) in the post-anastatic period.
4 - 6 Sv
Acute radiation poisoning, 60% fatality after 30 days (LD 60/30). Fatality increases from 60% at 450 rad to 90% at 600 rad (unless there is intense medical care). Symptoms start half an hour to two hours after irradiation and last for up to 2 days. After that, there is a 7 to 14 day anastasis, after which generally the same symptoms appear as with 300 to 400 rad irradiation, with increased intensity. Female sterility is common at this point. Convalescence takes several months to a year. The primary causes of death (in general 2 to 12 weeks after irradiation) are infections and internal bleeding.
6 - 10 Sv
Acute radiation poisoning, 100% fatality after 14 days (LD 100/14). Survival depends on intense medical care. Bone marrow is nearly or completely destroyed, so a bone marrow transplantation is required. Gastric and intestinal tissue are severely damaged. Symptoms start 15 to 30 minutes after irradiation and last for up to 2 days. Subsequently, there is a 5 to 10 day anastasis, after which the person dies of an infection or internal bleeding. Recovery would take several years and probably never be complete.
10 - 50 Sv
Acute radiation poisoning, 100% fatality after 7 days (LD 100/7). A dose this high leads to spontaneous symptoms after 5 to 30 minutes. After powerful fatigue and immediate nausea caused by direct activation of chemical receptors in the brain by the irradiation, there is a period of several days of comparable well-being, called the "walking ghost phase". After that, cell death in the gastric and intestinal tissue, causing massive diarrhea, intestinal bleeding and loss of water, leads to water-electrolyte imbalance. Death sets in with delirium and coma due to breakdown of circulation. Death is inevitable; the only treatment that can be offered is pain therapy.
50 - 80 Sv
Immediate disorientation and coma in seconds or minutes. Death sets in after a few hours by total collapse of nervous system.
>80 Sv
U.S. military forces expect immediate death."
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