Beta: Pre-engineering estimate (±20-30%). Engine uses real-world kill-fraction-per-pass from Nuvonic UVpro V-series + UVDI V-Mix + Signify SM345C + Kowalski 2009 (compact 85%, standard 90%, industrial 93%). PTFE inner reflection is IMPLICITLY included in these manufacturer numbers — not computed as separate boost. Real mixing patterns (cold-spot zones, occupant positioning) not modeled. Validate ACH target against VDI 6022 + manufacturer data. Closed-module units are IEC 62471 Risk Group Exempt — no occupant-zone baffle required. Keep ≥ 0.5 m clearance below the unit for unobstructed intake / outlet flow.