What must be worn at MOPP level 4 Afloat?

At MOPP (Mission Oriented Protective Posture) level 4 Afloat, the primary focus is on maximizing protection against chemical, biological, radiological, and nuclear (CBRN) threats while still allowing for operational effectiveness. The requirement to wear gloves and a mask/hood reflects the heightened protective measures needed at this level.

Gloves ensure that skin is protected from direct contact with hazardous agents, while the mask/hood is essential for respiratory protection as well as maintaining facial coverage to limit exposure. This combination is crucial in environments where the risks of contamination are significant, allowing personnel to operate safely.

Other options, while potentially relevant in specific contexts, do not fulfill the immediate requirement for protective gear at MOPP level 4. Decon supplies are more about response and hazard management, canteens are related to hydration rather than protection, and JSLIST (Joint Service Lightweight Integrated Suit Technology) is designed for protection but is not specifically mandated for wear at this MOPP level without the additional protective equipment specified in the correct answer.