Question

Negative pressure ventilation involves artificially lowering pressure inside the structure so that:

a) Smoke is pushed out
b) Fresh air is drawn in
c) Fire intensity increases
d) Airflow remains unchanged

Answer 1

Negative pressure ventilation involves creating a pressure lower than the atmospheric pressure inside a structure to draw fresh air in, which is similar to how breathing works in the human respiratory system.

Step-by-step explanation:

Negative pressure ventilation involves artificially lowering pressure inside the structure so that fresh air is drawn in. This concept stems from the definition of negative pressure, which is pressure lower than the atmospheric pressure. For instance, in the human respiratory system, during breathing, a negative pressure is created within the lungs which causes air to flow into the air spaces. Similarly, in mechanical ventilation systems, creating a negative pressure will cause outdoor air to flow into the building to replace the indoor air, potentially lowering pollutant levels and replenishing oxygen. Common examples of devices using the principles of entrainment to create negative pressure include aspirators and chimneys designed to ensure proper air circulation and gas exchange.