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The main factors affecting the decomposition of water by radiation include the following categories: radiation-related parameters, radiation type, and linear energy transfer (LET). High-LET radiation (such as alpha particles) results in a high degree of overlap between the radiation tracks, increasing the probability of reactions between free radicals and thus leading to a higher yield of molecular products； With low-LET radiation (such as gamma and X-rays), radical diffusion is more extensive, resulting in a higher production of radicals. Dose rate and absorbed dose: The equilibrium concentration of radiolysis products increases as the dose rate rises, while the product concentration rises initially with increasing absorbed dose before reaching a steady state. Environmental condition factors: Temperature: An increase in temperature accelerates the thermal decomposition of H₂O₂, while also altering the reaction rates of free radicals, thereby affecting the proportion of the final products formed. pH value: H⁺ and OH⁻ react with the primary active species generated by water dissociation, directly altering the concentration of free radicals and thus affecting the yield of molecular products. Pressure: Changes in pressure affect the equilibrium of gas product evolution, thereby indirectly altering the forward reaction rate of water dissociation. Impurity factors in water: Oxidizing/reducing impurities such as Br⁻ can eliminate free radicals like ·OH and H·, altering the pathways by which decomposition products are formed and affecting the G value (the number of water molecules decomposed per 100 eV of energy absorbed). Metal ions: Such as Cu²⁺, can promote the generation of H₂O₂ and gaseous H₂, thereby increasing the efficiency of water dissociation.