Selenium-75 Industrial Radioisotopes

Selenium-75 (Se-75) source is formed by compressing the Se-74 (or Se-74 compound) into the desired shape and encasing it in an outer capsule. The Selenium 75 sources we offer are either cylindrical or spherical.

Selenium-75 has a significantly longer half-life than Iridium-192.

The lower energy of Selenium-75 provides improved radiographic contrast sensitivity for thinner materials. This also translates to more effective shielding efficiency for collimators, portable shields, and radiography devices.

For a cylindrical source there are two dimensions quoted, 2x2mm for example refers to a source which is 2mm in diameter and 2mm in height. The dimensions of the source are always equal resulting in a source that is almost cubic in profile.

A spherical source has the Se-75 formed into a sphere. A spherical source is the best shape for radiography. The spherical Se-75 sources we offer give the highest activity for a given physical size resulting in high resolution and reduced time radiographs.

Energy Range (KeV)100-400
Half Life (days)119.8
Steel Working Thickness (mm)8-30