Here is a list of the most common x-rays. It includes the average percentage of particular types make up of all x-rays ie, dental x-rays account for one quarter of all x-rays done. It also shows how much typical background radiation is contained in a single x-ray. For instance a single dental x-ray exposes you in an instant to the equivalent of three days’ worth of background radiation.
Examination Radiation Equivalent % all x-rays Dose (milliSieverts)Dental 3 days 25 20
Limbs and joints 16 days 25 100
Chest 8 days 24 50
Spine 1 year 7 2200
(lumbar spine) 5 months 900
(thoracic spine)
Skull 1 month 5.6 200
Stomach & intestines 1.7 years 2.5 3800
(barium meal) 3.5 years 700
(barium enema)
Abdomen 8 months 2.9 1400
Pelvis 7 months 2.9 1200
Urinary system 2 years 1.3 4400