DEVELOPMENT OF AN ALGORITHM TO ESTIMATE EYE LENS DOSE IN TERMS OF OPERATIONAL QUANTITY Hp(3) USING HEAD TLD BADGE

Abstract

In view of the recommendations of International Commission on Radiological Protection for reduction of the occupational annual dose limit for eye lens from 150 mSv to 20 mSv/y, questions have been raised on the adequacy of monitoring for the quantities Hp(10) and Hp(0.07). As an immediate requirement, in the present situation, where there is no exclusive eye lens dosemeter in India, the existing chest TLD badge was modified to be used as head badge (head dosemeter) by including a strap to enable wearing on the forehead. In order to estimate the eye lens dose in terms of the operational quantity Hp(3), the prevalent algorithm of chest badge was also modified. The modified algorithm was applied to estimate Hp(3) for dosemeters irradiated to various beta and photon radiations including mixtures. The Q values (estimated/delivered dose equivalent) were found to be within ±20% for most of the photon beams.

Occupational Eye Lens Dose Over Six Years in the Staff of a Us High-Volume Cancer Center

“…Here, the eye lens dose is defined as dose at a depth of 300 mg cm −3 (0.3 cm) ( 28 , 29 ) . A regulatory method for calculating eye lens dose was not yet defined in US federal law and is an area of ongoing development ( 30–33 ) . Thus, under specific irradiation conditions, H p (0.07), or H p ( 9 ), may be used as a surrogate for H p ( 3 ).…”