A number of modern modalities are used to measure "Bone Mineral Density" (BMD); “Bone densitometry” best reveals the degree of bone loss.

Dual-energy X-ray absorptiometry (DEXA) is currently the most widely accepted and used method of measuring BMD.

The photo below is of a patient being scanned for bone density. The tech sits in the same room and the patient is fully clothed. Radiation levels are so low that it is safe for the tech to be in the room on a regular basis and there is no need for lead aprons.