Design Blueprint: Wildfire-Smoke Refuge Room for a Classroom or Clinic Ward

DESIGN BLUEPRINT — SIMULATED, NOT MEASURED — NOT BUILT. A build specification derived from the source paper (DOI 10.5281/zenodo.24108746) for a 180 m3, 30-occupant wildfire-smoke refuge room: four box-fan MERV-13 units sized for day-five filter loading (CADR falls to 0.549 by day five) hold 35 ug/m3 in mean smoke of 350 ug/m3 at US$0.514 per occupant per smoke day, with a four-unit HEPA alternative. Printed failure regimes: at peak smoke with no filter change only the HEPA class is feasible, and in leaky rooms (2.0 air changes per hour) neither class holds any target — sealing the room first is the correct intervention. Includes bill of materials, sizing law and scenario table, assembly, installation, commissioning, maintenance, and failure modes. Sole author: William Alexander Aldred (ORCID 0009-0000-1215-577X). CC BY 4.0.