Which of the following is not a component of fire suppression systems aboard vessels?

Fire suppression systems aboard vessels are specifically designed for the protection and fighting of fires that can occur in various environments on a ship. They typically include a range of equipment and tools that can effectively extinguish different types of fires, which can include electrical fires, flammable liquids, and ordinary combustibles.

Fire blankets, foam extinguishers, and CO2 extinguishers are all essential components of fire suppression systems. Fire blankets can smother flames, particularly in situations involving flammable liquids or clothing. Foam extinguishers are versatile tools designed to combat fires involving combustible liquids; they create a barrier between the fuel and the flames. CO2 extinguishers effectively displace oxygen around the fire, making them particularly useful for electrical fires without risking damage to electronic equipment.

Electric fans, however, serve a different purpose. While they can be useful in ventilation and aiding the dispersal of smoke, they do not play a direct role in suppression of fire. Instead, their potential use in a fire situation could inadvertently spread smoke or even flames if improperly applied. Therefore, they are not considered a component of fire suppression systems on vessels.