Proposals Based on the N0N Vector Aimed to Improve the Current System of Radiobiological Protection (CSoRP)

The objectives of our study are to describe irregularities of some aspects in the current system of radiobiological protection (CSoRP) and to propose actions aimed at overcoming these irregularities. In a previous study the E0 concept, which is the minimum element of the N0N vector or simple matrix, was introduced. N0N was initially called EN. N0N is composed of an increasing order of the normal tissue non-complication probability (NTCP0) values of all tissues or organs (ToOs) irradiated. The inappropriate treatment of the stochastic effects (SEs) has been the reason there are various irregularities in the CSoRP. This work shows descriptions of irregularities of some aspects in the CSoRP and our proposals aimed at improving this system. Although the current equivalent dose ( H ) is a total x-ray biological-equivalent absorbed dose (AD), its units are not AD ones. Contrary to H , the effective dose ( E ) is not based on any physical definition but was irregularly derived. The SEs must be evaluated with probabilistic metrics (PMs), not with other metrics, like the sievert (Sv), the unit of H and E. We propose some improvements, such as (1) to replace H with DX (total x-ray equivalent AD); (2) to discontinue the use of Sv or rem (roentgen equivalent man; 1 Sv = 100 rem) as H ’s units, and to use the DX units, like gray, AD’s unit in the SI (Gy); and (3) to use the DX in Gy and/or cGy for the occupational dose limits (ODLs).