The ICRP in its statement on tissue reaction from April 2011 (?1) recommended to reduce the annual dose limit to the lens of the eye from 150 mSv to 20 mSv (averaged over five years), with no single year dose exceeding 50 mSv. IAEA TECDOC 1731 (?2) and ISO 15382 (?3) were published as guidelines to the implementation of the new limits for occupational radiation.
The most accurate way to determine the dose to the lens of the eye is to use a dosimeter that is designed and calibrated for measuring Hp(3), but it will take some time (probably a couple of years) until such dosimetric system could be validated and implemented in routine monitoring. Meanwhile, in some cases, there is a need to estimate Hp(3), especially for retrospective reconstruction of dose to the lens of the eye. Therefore, in the following years, the measured values of Hp(10) and or Hp(0.07) can be used to calculate a conservative value for Hp(3).
The present paper discusses a new, more accurate and less conservative way to estimate Hp(3) using Hp(0.07) and Hp(10) quantities. This new method could be used also in reporting historical personal lens of the eye doses, when Hp(3) dosimeters were not used, and in some cases it could reduce the need to use special Hp(3) dosimeters in the future.