During the smouldering phase of a fire, what is the expected oxygen level in the room?

• A. Above 21%
• B. Between 15% and 21%
• C. Less than 15%
• D. Zero%

Answer: (C)

In the smouldering phase of a fire, the combustion process is characterized by lower oxygen levels due to the partial burning of materials. Generally, smouldering occurs when there is insufficient oxygen for a full-flame combustion process, causing the fire to burn at a lower temperature and produce smoke without an open flame.

During this phase, the oxygen level in the environment can drop significantly, often falling below 15%. This is because smouldering fires consume available oxygen as they slowly burn, resulting in an atmosphere that can become deficient in oxygen. A drop to this level poses serious health risks, making it vital to monitor air quality and ensure adequate ventilation in any area experiencing smouldering conditions.

Understanding this dynamic is key in both fire prevention and safety protocols, reinforcing the necessity for immediate action when oxygen levels drop in potential fire situations.