How does ASHRAE 170 interact with FGI Guidelines?
ASHRAE 170 and the FGI Guidelines are companion documents by design: 170 originated in an agreement between ASHRAE and FGI that ventilation requirements belonged in an ASHRAE standard, and the FGI Guidelines reference Standard 170 for ventilation rather than duplicating it. FGI sets the program, space, and planning requirements (what rooms, how big, adjacencies); 170 sets the ventilation engineering (ACH, pressure, filtration, temperature, humidity) for those spaces. The 2021 edition restructured 170 into hospital, outpatient, and residential sections mirroring FGI’s own three documents.
How they divide the work
- FGI decides: which spaces a facility needs, minimum sizes and clearances, room relationships and adjacencies.
- ASHRAE 170 decides: how each of those spaces is ventilated — air changes, pressure relationships, filtration, temperature, humidity.
- Neither duplicates the other: FGI points to 170 for ventilation numbers; 170 points to FGI space definitions (its tables cite FGI section numbers).
The 2026 rename
With FGI’s 2026 documents renamed from “Guidelines” to FGI Codes, the relationship continues — the Codes still reference ASHRAE 170 for ventilation. When your state adopts an FGI edition into code, it effectively adopts the referenced 170 requirements with it. Always confirm which editions of each document your AHJ enforces — a 2026 FGI Code paired with an older adopted 170 is a common real-world combination.
Practical takeaway
Design teams need both documents open: FGI for the room, 170 for the air. A design that satisfies FGI’s space requirements but misses 170’s ventilation table — or vice versa — fails review.
FGI draws the room. 170 moves the air.
See what the FGI Guidelines are and recent ASHRAE 170 changes.
FAQ
Does FGI include ventilation requirements?
FGI references ASHRAE 170 for ventilation rather than duplicating it — the two are companion documents.
Which comes first, FGI or ASHRAE 170?
They work together: FGI defines the spaces, 170 defines their ventilation. Design teams need both.
Do the 2026 FGI Codes still use ASHRAE 170?
Yes — the renamed FGI Codes continue to reference Standard 170 for ventilation requirements.