For safety reasons, combustion chambers should be monitored for what?

The correct choice highlights the importance of maintaining safety in combustion chambers by monitoring for debris build-up. Combustion chambers can accumulate soot, dust, or other materials that may obstruct airflow or create conditions for improper combustion. This debris can lead to several safety hazards, including reduced efficiency, increased emissions, and even the risk of fire or explosion if not addressed. Regular inspections for debris ensure that the system operates efficiently and safely, preventing potential blockages that could lead to hazardous situations.

While other factors like moisture content, fuel type, and air pressure play roles in the overall performance and safety of combustion systems, the direct monitoring for debris build-up specifically focuses on a critical issue that can immediately affect safety.