**3.4 The geometry of irradiated object**

Biological objects exposed to accelerated electrons, such as foodstuffs and materials used in transplantology may have complex geometry that can be dramatically different from parallelepiped. A parallelepiped is regarded as a perfect shape for irradiation because its simple geometry allows electrons to penetrate the object perpendicularly to its surface. Exposure of more complex geometries, such as a sphere, an ellipsoid, or a cylinder, to electron beams, however, does not permit the perpendicular penetration of electrons into the surface layer, making the depth dose distribution irregular and less predictable. **Figure 4** is a 3D-color representation of the absorbed dose distribution over a parallelepiped with the edge of 6 cm, a ∅ 6 cm sphere, and a ∅ 6 cm cylinder simulated as water phantoms as they are unilaterally irradiated with 10 MeV electrons.

As it can be seen from **Figure 4**, the distance at which the absorbed dose reaches its maximum changes with the change in the object shape. In the case of the parallelepiped, as the electrons start penetrating the volume, the dose increases slightly but when the depth exceeds 2 cm the dose drops to zero at the distance of 5 cm from the surface *Electron Beam Processing of Biological Objects and Materials DOI: http://dx.doi.org/10.5772/intechopen.112699*
