Ventilation
ASHRAE 170
ANSI/ASHRAE/ASHE Standard 170 — Ventilation of Health Care Facilities
Scope
Standard 170 specifies minimum ventilation requirements for hospital, outpatient, and residential health-care spaces. It defines air changes per hour (ACH), pressure relationships, filtration efficiency, and temperature/humidity ranges for every functional space in a hospital, including the patient room and airborne infection isolation room.
Where it applies in the room
- Total and outdoor air changes per hour by room type
- Pressure relationship (positive, negative, neutral) versus adjacent spaces
- Filtration MERV / HEPA requirements
- Temperature and relative humidity ranges
Key requirements at a glance
| Med-surg room | 6 total ACH, of which 2 are outdoor; pressure neutral to corridor. |
|---|---|
| ICU room | 6 total ACH, of which 2 outdoor; pressure neutral to corridor. |
| AIIR (isolation) | ≥ 12 ACH new / ≥ 6 existing; negative to corridor by ≥ 0.01 in. w.c. |
| Protective environment room | ≥ 12 ACH; positive to corridor; HEPA-filtered supply. |
Summarized for reference. Consult the source document for the definitive text.
Source & further reading
- · ASHRAE Standard 170 — publisher page — publisher
- · ANSI/ASHRAE/ASHE 170-2021 (Techstreet listing) — official edition
Also known as
- ANSI/ASHRAE/ASHE Standard 170
- ASHRAE Standard 170
- ASHRAE 170
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Cited in
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