Personal dose equivalent

The dose equivalent in soft tissue at an appropriate depth, d, below a specified point on the human body. The soft tissue is ICRU 4-element tissue. The unit of personal dose equivalent is joule per kilogram (J kg^-1), and its special name is Sievert (Sv). The specified point is usually given by the position where the individual dosimeter is worn. For the assessment of effective dose a depth of 10 mm is recommended, and for the assessment of equivalent dose to the skin and the lens of the eye, depths of 0.07 mm and 3 mm, respectively, are recommended.

ICRP Publication 116, 2010

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from ICRP Publication 139, 2018

The operational quantity for individual monitoring is the personal dose equivalent H_p(d) which is the dose equivalent in soft tissue at an appropriate depth d (in mm) below a specific point on the human body. The unit of personal dose equivalent is J kg^-1 and its special name is sievert (Sv). The specified point is usually given by the position where the individual’s dosimeter is worn. For monitoring effective dose the operational quantity H_p(10) is used and for assessment of the dose to the skin hands and feet the personal dose equivalent H_p(0.07) is used. A depth d = 3 mm is adequate for monitoring the dose to the lens of the eye. In practice however in many countries calibration of dosimeters in terms of H_p(3) has not been implemented but H_p(0.07) can be used for the same monitoring purpose for photon radiation which is the case in interventions guided by radiological imaging.

from ICRP Publication 103, 2007

An operational quantity: the dose equivalent in soft tissue (commonly interpreted as the ‘ICRU sphere’) at an appropriate depth, d, below a specified point on the human body. The unit of personal dose equivalent is joule per kilogram (J kg^-1) and its special name is Sievert (Sv). The specified point is usually given by the position where the individual’s dosimeter is worn.