It is reasonable to ask about radiation before an X-ray. The answer is not simply that all X-rays are low dose. The amount depends on the body part, the number of images, the equipment, and the patient's size.
For an average adult, a chest X-ray is often estimated at about 0.1 mSv, similar to roughly 10 days of natural background radiation. An X-ray of a hand or foot is much lower. These comparisons are approximate, not a prediction of one person's exact dose.
What the risk means
Ionising radiation can affect cells, so unnecessary exposure should be avoided. At the low doses used for ordinary diagnostic X-rays, any added long-term cancer risk is considered small and difficult to measure precisely.
The useful comparison is between that small possible risk and the reason for the examination. Missing a fracture, chest infection, bowel obstruction, or another important problem may carry a more immediate risk.
How exposure is kept down
The radiographer selects settings for the body part and patient, limits the beam to the area being examined, and avoids repeat images where possible. This follows the principle of keeping radiation as low as reasonably achievable while still producing an image that can answer the clinical question.
You may notice that protective shielding is not used routinely for every examination. Modern guidance has changed because a shield can sometimes cover important anatomy, interfere with automatic exposure controls, or cause a repeat image. The team will use the approach that best fits the examination and equipment.
Pregnancy and X-rays
Tell the radiographer if you are pregnant or may be pregnant, especially when the abdomen or pelvis will be examined. Pregnancy does not make every X-ray impossible. An X-ray away from the pelvis usually gives the fetus very little exposure, while an urgent examination may be safer than delaying diagnosis.
The radiology team will consider the body part, stage of pregnancy, urgency, and whether ultrasound or MRI could answer the same question.
The bottom line
An X-ray uses radiation, but the dose and risk are not the same for every examination. The right question is whether the X-ray is justified and performed with an appropriate technique for you.