The basic assumption in radiation protection is that stochastic risk is directly proportional to dose. Underground laboratories give the opportunity to test the linear no-threshold (LNT) model for which below the averave natural environmental background no detriment is expected.

Ref：Maria Antonella Tabocchini, The underground biology at the INFN Gran Sasso National Laboratory. Fifth International Workshop for the Design of the ANDES Underground Laboratory Towards the ANDES laboratory flag-ship and further experiments Buenos Aires, Argentina 29-30 June 2017.