What is the duration for a white phosphorus (WP) round before it expires?

In the context of white phosphorus (WP) rounds, the duration before expiration is critical for effective use in military operations. The correct answer reflects that WP rounds have a specific dwell time after they are fired, which is essential for planning and execution in fire missions.

The 30 seconds associated with WP rounds indicates the time period during which their effectiveness in terms of illuminating or marking an area, as well as their incendiary properties, is utilized optimally. This period allows troops to engage targets effectively while considering the safety and tactical implications associated with handling WP.

Understanding this time duration helps facilitate coordinated efforts between ground forces and artillery units, ensuring that the smoke or incendiary effects of the WP are maximized while minimizing hazards associated with their use. Therefore, recognizing the 30-second standard for WP rounds is crucial for efficient operational planning in the field.