Ambient dose equivalent

The operational dose quantity ambient dose equivalent (H^*(d)) is defined as the equivalent dose at point P at a depth of d mm in the ICRU-sphere (see Figure). The corresponding unit is sievert (Sv).

It is assumed that the radiation field anywhere within the sphere is equal to that at point P (extended field) and that all radiation comes from the direction parallel to the shortest connection between the spherical surface and point P (aligned field).

One distinguishes H^*(10) for penetrating radiation, H^*(3) for the lens of the eye, and H^*(0.07) for the skin.

Related quantities

• absorbed dose
• collective effective dose
• committed effective dose
• committed equivalent dose
• directional dose equivalent
• effective dose
• equivalent dose
• exposure
• irradiation geometry
• kerma
• personal dose equivalent
• radiation weighting factor
• tissue weighting factor