Human response to personalized ventilation and mixing ventilation.

Area of Science:

• Building Science
• Environmental Health
• Human Factors Engineering

Background:

• Traditional mixing ventilation (MV) systems often fail to meet diverse occupant needs for thermal comfort and air quality.
• Personalized ventilation systems (PVS) offer individual control over microclimate conditions.

Purpose of the Study:

• To compare the effectiveness of a personalized ventilation system (PVS) against mixing ventilation (MV).
• To evaluate occupant responses in terms of perceived air quality, thermal comfort, Sick Building Syndrome (SBS) symptoms, and performance.

Main Methods:

• Sixty human subjects were exposed to either PVS or MV for 3 hours and 45 minutes.
• PVS allowed individual control of air terminal device positioning and airflow rate.
• Room air temperatures were maintained at 23°C and 26°C for comparison.

Main Results:

• PVS significantly improved perceived air quality and reduced SBS symptoms compared to MV.
• The percentage of dissatisfied occupants regarding air quality decreased from 22% with MV to 7% with PVS at 23°C.
• Headache and cognitive clarity issues were least intense with PVS using outdoor air at 20°C; PVS also increased self-estimated performance.

Conclusions:

• Personalized ventilation systems offer superior thermal comfort and perceived air quality over mixing ventilation.
• Occupants effectively utilize PVS controls to achieve preferred microenvironments within standard indoor climate ranges.
• Further development of efficient air terminal devices for PVS is recommended.