ASHRAE Hospital Design 100% Ingres & Egress of O.A

[onlinework]

Dear et al!

According to ASHRAE Hospital design minimum outdoor air requirment for the healthcare fascilities. like ICU, 100% Outdoor air is recommended. Instead of All air exhausted to outdoor, it implies to Dash (-). What does it mean?. Is it optional to exhaust or recirculate with HEPA filter?.

Please comment

Regards
Himayath100

 

[urgross]

HEPA'd return, 16 ACH, with 4 ACH OA is the ASHRAE standard.