Shielding design of radiation areas requires comprehensive consideration of the environment. However, the
current situation is that the thickness of shielding materials is conservatively designed to reduce risk factors,
and thickness standards are basically calculated using a formula to estimate the shielding before design. This
research proposes a hybrid method for optimal shielding thickness that combines simulation and actual data.
Dose conversion factor (DCF) calculated in 1.5 mm lead situation, compared with MCNP and Actual dosimeters
(PED, CD-Gam-1), and the lead shielding design of the five types from 0.25 mm lead to 1.25 mm lead was
simulated with a 0.25 mm lead interval, and evaluation areas was divided into radiation workers (< 20 mSv/yr)
and patients (< 1 mSv/yr) in detail. When applying PED-DCF and CD-Gam-1-DCF, the result was a lead thickness
reduction of up to 1.25 mm lead. Therefore, we propose a radiation protection facility inspection method
designed in hybrid.