Ventilation
Ventilation is the process of supplying outdoor air to indoor spaces to maintain air quality, dilute contaminants, and regulate humidity and temperature. It is essential for occupant health, comfort, and compliance with building codes. Ventilation rates are determined by occupancy, floor area, and contaminant sources, and are often specified by standards such as ASHRAE 62.1. Ventilation can be natural (through openings and wind-driven flow) or mechanical (using fans and duct systems). Key parameters include airflow rate (V̇), air changes per hour (ACH), and energy impact due to conditioning of outdoor air. Engineers must balance indoor air quality with energy efficiency, using strategies such as demand-controlled ventilation, heat recovery ventilators, and economizers.
Knowledge Check
1.What is the primary purpose of ventilation in buildings?
2.Which two main types of ventilation are used in buildings?
3.If a room has a volume of 300 m³ and receives 600 m³/h of outdoor air, what is the air change rate (ACH)?
4.What standard commonly specifies minimum ventilation rates in buildings?
5.What is demand-controlled ventilation (DCV)?
6.Why is heat recovery used in ventilation systems?
7.What is the main drawback of increasing ventilation rates excessively?
8.Which parameter directly measures ventilation effectiveness?
9.What is natural ventilation primarily driven by?
10.Why is ventilation critical in industrial processes?