Passive ventilators, such as cowl vents, clamshell vents, louvers, grilles, ventilating sails, ports and hatches simply provide an access path for air to enter or leave the interior of the boat.

• 自然通风通风口，如整流罩通风口，蛤壳式通风口，百叶通风，格子窗通风，船航行中的风，舷窗和舱盖都给空气流通提供一条路径给空气进入或者流出船内。