What must E2 monitor and report to E3?

The requirement for E2 to monitor and report to E3 aligns with essential operational protocols during firefighting efforts. In this scenario, E2 is responsible for monitoring residual pressure, which is crucial for ensuring the integrity of the water supply system during firefighting operations. Residual pressure indicates how much pressure is available after water has been drawn from the system, directly impacting the effectiveness of the water supply at the nozzle.

Additionally, any changes in gallons per minute (GPM) being flowed must be reported, as this directly affects water delivery and can influence tactical decisions in firefighting. Both residual pressure and changes in GPM are critical parameters that help ensure adequate and effective fire suppression, making this the correct choice for what E2 should communicate to E3. Maintaining awareness of these metrics aids in managing water resources effectively, especially in dynamic situations where flow needs may rapidly change.