Effects of Acute Radiation

 

The worldwide average background dose for a human being is about 2.4 millisievert (mSv) per year.[3]

 2.4mSv = 240 mrem

 

Phase

Symptom

Exposure (Sv)

1–2Sv

2–6Sv

6–8Sv

8–30Sv

>30Sv

Immediate

Nausea and vomiting

5–50%

50–100%

75–100%

90–100%

100%

Time of onset

2–6h

1–2h

10–60m

<10m

Immediate

Duration

>24h

24–48h

<48h

<48h

48h–death

Diarrhea

None

Slight (10%)

Heavy (10%)

Heavy (90%)

Heavy (100%)

Time of onset

—

3–8h

1–2h

>1h

<30m

Headache

Slight

Mild (50%)

Moderate (80%)

Severe (80–90%)

Severe (100%)

Time of onset

—

4–24h

3–4h

1–2h

<1h

Fever

Slight–None

Moderate (50%)

High (100%)

Severe (100%)

Severe (100%)

Time of onset

—

1–3h

>1h

>1h

>30m

CNS function

No impairment

Cognitive impairment 6–20 h

Cognitive impairment <20 h

Rapid incapacitation

Seizures, Tremor, Ataxia

Latent Period

 

28–31 days

7–28 days

>7 days

none

None

Overt illness

 

Mild Leukopenia;
Fatigue;
Weakness

Leukopenia;
Purpura;
Hemorrhage;
Infections;
Epilation

Severe leukopenia;
High fever;
Diarrhea;
Vomiting;
Dizziness and disorientation Hypotension;
Electrolyte disturbance

Nausea;
Vomiting; Severe diarrhea;
High fever;
Electrolyte disturbance;
Shock

Death

 

Mortality without medical care

0–5%

5–100%

95–100%

100%

100%

 

Mortality with medical care

0–5%

5–50%

50–100%

100%

100%

1 rem=0.01 Sv, 1mrem=0.00001Sv = 0.01mSv

1Sv=100rem, 1mSv=100mrem