Which item is NOT recommended to use when handling a fire on a vessel?

Using water to extinguish grease fires is dangerous and not recommended. Grease fires occur when oils or fats ignite and can reach very high temperatures. When water is applied to a grease fire, it can cause the burning oil to splatter and spread the flames, potentially making the situation much worse and creating a larger fire hazard.

In contrast, fire extinguishers are specifically designed to tackle various types of fires, and using them as needed is crucial for effective fire response. Fire blankets can help smother flames safely in some situations, while baking soda can be an effective method for suppressing small grease fires, as it works by suffocating the fire and disrupting the chemical reaction. Thus, it is essential to avoid water for grease fires to prevent escalation and ensure safety during fire handling on a vessel.