At which MOPP Level is the Counter Measure Wash Down (CMWD) System continuously activated?

The Counter Measure Wash Down (CMWD) System is designed to protect a naval vessel from chemical, biological, or radiological contamination by continuously washing the ship's surfaces with seawater. This system is activated at MOPP Level IV, where the threat level is considered the highest, and the ship is in a state of readiness to counter immediate and significant threats.

At MOPP Level IV, the crew is fully geared and prepared for the most severe conditions. Continuous operation of the CMWD during this level ensures that any potential contamination is managed proactively, thus maintaining the integrity of the ship’s environment and protecting the personnel onboard. In contrast, at MOPP Levels I, II, and III, the system may not be activated continuously as the threat level is lower and the focus may be on readiness to respond rather than on active contamination prevention.