A baseline health assessment is the initial medical evaluation conducted before a worker begins duties that involve exposure to workplace hazards or safety-sensitive functions. It establishes a benchmark for comparison during subsequent periodic and exit examinations in medical surveillance programs. The assessment typically includes: comprehensive medical history, physical examination, vital signs and anthropometric measurements, vision and hearing testing, spirometry (if respiratory exposures are anticipated), laboratory work (blood counts, metabolic panel, urinalysis), and any hazard-specific testing required by OSHA standards. Results help determine initial fitness for duty and identify pre-existing conditions that might be aggravated by workplace exposures.