What is the purpose of sealing and securing ventilation when a fire is present?

• A. To isolate the fire, reduce smoke spread, and protect escape routes and critical spaces
• B. To increase oxygen in the space
• C. To vent smoke into other compartments
• D. To cool the external hull

Answer: (A)

Sealing and securing ventilation during a fire aims to starve the fire of fresh air and keep hot smoke from moving between spaces. By shutting off ductwork and dampers, you create tight compartments that slow or stop flame spread, limit smoke in escape routes, and protect critical spaces and equipment. This helps the crew reach and fight the blaze more safely and preserves routes for evacuation.

Increasing oxygen would feed the fire, venting smoke into other compartments would spread the hazard, and cooling the external hull isn’t achieved through interior ventilation control.