The most demanding ventilation project in the entire program — ASHRAE 170 pressure relationships, room-by-room air change rates, 100% outdoor air isolation spaces, and N+1 redundancy on critical air handling.
The project brief: a 420,000-square-foot, 200-bed acute-care hospital governed by ASHRAE 170 (Ventilation of Health Care Facilities) rather than the general-purpose ASHRAE 62.1 used elsewhere in this program — a code that assigns a different pressure relationship, air change rate, and recirculation rule to nearly every room type in the building.
This module walks the whole ventilation design the way a real health care mechanical engineer would: why operating rooms are positive pressure while isolation rooms are negative, the worked air-change-rate calculations behind an OR's 1,500 cfm total supply and an isolation room's fully-outdoor-air 288 cfm supply, which spaces must run 100% outdoor air with zero recirculation and why, and how the central plant and critical-space air handlers are built with N+1 redundancy and continuous pressure monitoring so a single failure never lets a room's pressure relationship lapse. The full worked numbers, complete bill of materials, and finished design reasoning are part of the unlocked module below.