Lead-free/lead-composite nuclear radiation protection materials are becoming increasingly prevalent in military applications to safeguard the health and safety of military personnel. Currently, accurate measurement and tracing of the shielding performance of military nuclear radiation protective clothing is difficult.

This study aims to measure lead equivalent in nuclear radiation protection materials for satisfying the radiation performance evaluation requirements of international mainstream military radiation protective clothing.

Firstly, a device to measure lead equivalence in protective clothing was developed. Then, the reference radiation mass for lead equivalence at a photon energy of 130 keV was determined using a combination of Monte Carlo simulation and experimental measurements. Finally, the shielding performances of a standard lead sheet were assessed using developed device under narrow beam conditions, and shielding performances of military nuclear radiation protective clothing materials produced by a few manufacturers were tested in the same conditions.

Evaluation results show the relative expanded uncertainty of lead equivalent measurement results for standard lead sheet and military nuclear radiation protective clothing samples correspond to 4.2% (k=2).

This study identifies measurement conditions for subsequent performance tests of additional military nuclear radiation protective materials prior to delivery.