Design Rules🔧 Building Services

HVAC Fresh Air per Person — Office

Minimum fresh-air ventilation per person in office buildings
See also📖 NBC 2016🔗 NBC 2016🧮 RCC Design📒 Handbook Topic
8.5
L/s/person
(≈ 18 cfm)
8.5L/s/personmin fresh air in office spacesFRESH AIR
Primary value8.5 L/s/person ((≈ 18 cfm))
Applies toOffice buildings · Conference rooms · General assembly spaces
ExceptionsConference rooms / dense occupancy10 L/s/person
Hospitals / patient rooms10-12 L/s/person
Restaurant dining areas9-10 L/s/person
Minimum requirement per NBC 20163.8 L/s/person for offices, conference rooms, and assembly halls.
Hospitals (Patient Rooms) per NBC 201612.5 L/s/person
Smoking Lounges per NBC 201630 L/s/person
Measured asOutdoor (fresh) air supplied per person at design occupancy. Excludes recirculated air.
SourceNBC 2016NBC 2016 Part 8, Section 3, Table 5 (for minimums); ISHRAE/ASHRAE Standard 62.1 (for performance-based design)
📚 Cross-referenced
Why this matters

Fresh air dilutes indoor pollutants like CO₂, VOCs from furnishings, and bio-effluents. Inadequate ventilation, especially in densely occupied Indian offices, can lead to 'sick building syndrome', causing drowsiness, headaches, and reduced cognitive function, which directly impacts employee productivity and well-being.

Typical practice

Modern Grade A office buildings in India often use Demand Controlled Ventilation (DCV). CO₂ sensors monitor occupancy in real-time, adjusting fresh air intake to maintain CO₂ levels below 1000 ppm, thus optimizing both indoor air quality and energy consumption.

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