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Background/Objectives Repetitive low-level blast (LLB) exposure during military training is a recognized occupational hazard with potential cognitive and mental health implications. Although high-level blast effects have been well studied, the long-term impacts of repeated LLB exposure remain poorly understood. Symptoms reported include disturbed sleep, irritability, headaches, and cognitive changes, yet objective, sensitive measures to assess these effects remain limited. This study aims to evaluate the acute and chronic effects of LLB exposure on balance, neurocognitive function, and mental health in Australian Defence Force members.Methods Twenty-four Australian Special Forces trainees participated in this pilot study. Blast exposures were measured using BlackBox Biometrics Blast (B3) gauges, recording peak overpressure (psi) and cumulative impulse (psi·ms). Baseline assessments included balance, neurocognitive function (SWAY tool: reaction time, impulse control, working memory), and mental health (Pittsburgh Sleep Quality Index, PHQ-9, GAD-7). Post-exposure assessments were conducted following training events with significant blast exposure thresholds (>4 psi or >100 psi·ms).Results Participants fired 66mm and 84mm weapon systems, with positive blast impulse 2–3 times higher for the 84mm. No significant changes were observed in balance, neurocognitive performance, or mental health measures between baseline and post-exposure. Sleep disturbances were minimal and primarily linked to insufficient sleep duration.Conclusions Preliminary findings suggest current LLB exposure levels during training are unlikely to cause measurable neurocognitive or psychological effects. Future studies incorporating blood-based biomarkers may enhance sensitivity in detecting earlier subclinical changes. This research forms the foundation of a PhD project commencing in 2025 to further investigate the long-term impacts of repetitive LLB exposure.