FMC 403.3.1.1 – Minimum Outdoor Air Worksheet Single Zone

This worksheet is designed to teach the manual process. You still have to look up the correct row in FMC Table 403.3.1.1 and enter the values (Rp, Ra, Ez, exhaust rate, and occupant density if applicable).
Single zone only: if your building/system has more than one zone, start a new worksheet (clear and re-use this page) for each zone.

Tip for novices: Start with Space Type → find the matching row in Table 403.3.1.1 → copy Rp and Ra → enter Area and Occupant density → then enter Ez. Watch the math fill in.
How the sheet computes People: Total = Area × Occupant Density; People = (Total ÷ 1000) rounded up to the next whole person (per space).
Space type / use (from Table 403.3.1.1) Area (ft²) Occ. density
(people/1000 ft²)		 Total
(Area×Density)		 ÷1000 Total people
(for area)		 Rp
(cfm/person)		 People OA
(Rp×People)		 Ra
(cfm/ft²)		 Area OA
(Ra×Area)		 Total OA
(People+Area)		 Ez
(Table 403.3.1.1.1.2)		 Adjusted OA
(Total OA÷Ez)		 Exh rate
(cfm/ft²)		 Total exh
(rate×Area)		 Row
Zone totals (Single Zone) — these are the totals you would typically report for the zone.
Total area (ft²)
0
Total people (calculated)
0
Total people OA (cfm)
0
Total area OA (cfm)
0
Total OA (cfm)
0
Total adjusted OA (cfm)
0
Sum of (Total OA ÷ Ez)
Total exhaust (cfm)
0
Reminder: This page is a teaching worksheet. If you like this teaching tool, please check out our Ventilation Calculator!