Human Factors
Human Factors tests the link between the built environment and occupant comfort, health, safety, and performance, and how to measure that link.
Comfort and indoor environmental quality
Thermal comfort is a range, not a setpoint: it depends on air temperature, mean radiant temperature, humidity, air speed, clothing, and activity level. Ventilation rates follow the applicable ventilation standard, with CO2 used as a practical indicator of occupancy-adjusted fresh-air adequacy. Lighting needs task illuminance plus glare control; daylight and views correlate strongly with satisfaction. Acoustics is usually the top complaint driver in open plan, and speech privacy depends on background noise and absorption, not on decibels alone.
Ergonomics and design
Anthropometric ranges (5th to 95th percentile) drive adjustability: desk height, monitor position, chair fit. Accessibility codes set minimums. Density and privacy trade directly against real estate cost.
Worked example
A floor of 120 desks is densified from 12 to 9 square metres per person. Noise complaints rise to 40. Before buying white-noise masking, check the pattern: complaints cluster beside the collaboration zone. The response is to relocate collaboration into enclosed rooms, add absorption at the boundary, and set a behaviour protocol, then re-survey at 60 days. The reasoning shown is: fix the source and the geometry first, add masking last, and verify with the same survey instrument.
Measurement
Occupant satisfaction surveys with consistent scales and reported response rates, paired with objective data such as CO2, temperature logs, and comfort-related work orders.
Traps
- Treating one loud complaint as representative.
- Using a single setpoint instead of a comfort range.
- Assuming density savings carry no productivity cost.
- Designing for the average person instead of a percentile range.