Which ventilation technique uses a smoke ejector to pull combustion products out through openings?

The correct answer is negative pressure ventilation. This technique involves the use of smoke ejectors or fans to create a lower pressure in a specified area, effectively drawing smoke and other combustion products out through designated openings. By establishing a negative pressure environment, the smoke ejectors help to improve visibility and air quality inside the structure, allowing for safer and more effective firefighting efforts.

In contrast, positive pressure ventilation pushes air into the structure, which can sometimes be beneficial for creating airflow but is not effective for removing smoke. Natural ventilation relies on natural airflow through openings without mechanical assistance, and mechanical ventilation is a broader term that encompasses various methods, including both negative and positive pressure techniques. Understanding the distinctions between these ventilation methods is crucial for effective smoke removal and fire control strategies.