Abstract: During the detection of releasers from nuclear fuel plants, the isotope ⁸⁵Kr presents a challenge due to its exceptionally low γ branching ratio of approximately 0.434% and the complex bremsstrahlung mechanism that follows β radiation, where the branching ratio exceeds 99.5%. This complexity complicates the precise inversion of ⁸⁵Kr activity within a sealed container. To investigate the interference effects under realistic working conditions, a cylindrical three-dimensional model was developed. Dynamic analyses were performed to assess the effects of varying container wall thickness (0.5-1.5 mm), container material (aluminum, brass, stainless steel), ⁸⁵Kr source gas pressure (1.0-5.0 atm), and container inner diameter (1.9-5.9 cm). The dose rate response function and bremsstrahlung radiation leakage ratio were compared across these variables. The results indicate that: (1) The wall thickness of the container is significantly negatively correlated with the proportion of bremsstrahlung leakage, leading to nonlinear distortion of the dose rate response function in the near-field area. This finding suggests that wall thickness tolerance is a primary source of systematic error; (2) Low-Z materials, such as aluminum, due to small photoelectric cross-sections and low mass thicknesses,exhibit poor self-absorption of low-energy photons, resulting in a markedly higher proportion of bremsstrahlung leakage compared to high-Z materials, such as brass; (3) The gas pressure of the radioactive source demonstrates a significant positive correlation with the proportion of bremsstrahlung radiation leakage. However, under the same detection distance, the dose-rate response function remains largely unchanged; (4) The inner diameter of the container reveals a significant nonlinear relationship with the proportion of bremsstrahlung leakage. Nevertheless, containers with a larger inner diameter substantially reduce the effective detection efficiency per unit activity. This research establishes a correction model for geometric parameters and pressure variations within the container during the ⁸⁵Kr activity inversion process, thereby providing a theoretical foundation for enhancing the accuracy of the ⁸⁵Kr online monitoring system and the precision of the inversion system, which holds considerable reference value for engineering applications.