SOME PERSPECTIVES ON RADIATION LEVELS

---

A few Dose-Effect Levels
(Note, levels are Approximate.)

Lethal Whole Body Acute Dose:	500 rem (5 Sv)
Minimum Acute Whole Body Symptomatic Dose:	100 rem (1Sv)
Dose below which we have little direct evidence of harm:	10 rem (0.1 Sv)
Background Radiation:	0.3 rem or 300 mrem per year (3 mSv per year)

(Background radiation can easily vary by more than a factor of 2.)

---

Doses to Irradiated Tissues

CT scan	1 to 5 rem (1,000 to 5,000 mrem)
Mammogram	150 to 300 mrem (0.15 to 0.3 rem)
Abdominal X-ray	50 to 500 mrem (0.05 to 0.5 rem)
Chest X-ray	5 to 10 mrem (0.005 to 0.01 rem)

The effective dose from a chest x-ray is less than that from a cross country airline flight.

 

The average equivalent dose to the bronchial epithelium of a smoker is about 16 rem per year.

 

Some long interventional procedures can produce skin doses in excess of 200 rem (2 Sv) which can produce skin damage.

 

---

Typical Dose to Radiation Workers
(Note: many receive no measurable doses.)

(exposed surface)	50-1000 mrem/year (0.5-1 rem/year)
(under lead apron)	1-20 mrem/year (0.001-0.02 rem/year)
(to embryo-fetus-under lead apron)	less than 10 mrem during gestation

---