What is space-by-space ventilation?

• A. Calculating or applying ventilation rates for individual spaces rather than a single system-wide rate.
• B. Using only one central ventilation rate
• C. Ventilation only for spaces with windows
• D. Ventilation rates based on outdoor temperature

Answer: (A)

Space-by-space ventilation means you determine and deliver outdoor air based on the needs of each individual space, not a single rate applied to the whole building. Each space has its own minimum outdoor air requirement determined by how many people use it, how big it is, and what it’s used for. The building’s total ventilation is then the sum or appropriate distribution of these per-space requirements, with controls that can adjust to actual occupancy (demand-controlled ventilation). This ensures rooms with higher occupancy or more likely to generate contaminants get enough fresh air, while smaller or less-used spaces aren’t over-ventilated, improving IAQ and energy efficiency. Relying on one central rate would mis-match ventilation to many spaces’ needs; spaces without windows still require ventilation, and rates aren’t set by outdoor temperature in this approach, though temperature can influence energy-saving strategies.