5901 23RD DR W ZAP ENERGY 2025-08-04

ZAP ENERGY ZRD-SPL-001 1.5 Methodology of Dose Exposure Estimation and Shielding Design 1.5.1 Monte Carlo Simulation The dose estimation for the Everlab facility was done by using a three-dimensional Monte Carlo simulation code, PHITS (Particle and Heavy Ion Transport code System) version 3.33 [3]. The PHITS code is a general-purpose Monte Carlo particle transport code developed to track interactions of most radiation species with matter over a broad range of energies. The code has a similar function to the Monte Carlo N-Particle (MCNP) transport code, FLUKA, GEANT4, and several other general-purpose simulation codes. It has been widely used for shielding design for nuclear facilities, activation analysis, dosimetry, and many health and medical physics applications. The code has been comprehensively benchmarked and validated for these applications [4]. 1.5.2 Simulation Geometry and Lab Coordination In the PHITS simulation model, the entire Everlab facility and the surroundings are included in the geometry. The model covers 20 m extended from the East of Suite 100, 19 m away from the South of the HV lab, 8 m West to Suite 101, 18 m North from the building, as shown in the orange dash line enclosed in Figure 1. The model also includes dry air of 25 m above the machine height to consider the sky shine. A three-dimensional model showing the building structure is presented in Figure 4. The laboratory space is in a Cartesian coordinate centered at the nose cone tip inside the FUZE-Q Z-pinch fusion device. The +X coordinate is facing towards the East, the +Z coordinate is facing towards the South, and the+Y coordinate is facing up. 2 Air 7�� acuum Plywood Figure 4 Three-dimensional model showing the building structure for Suite 100.The roof is modeled but hidden here for display purposes. Zap Energy Inc. Proprietary Information 5