What type of wall is capable of restricting smoke and flames for 30 minutes or longer?

A Class B bulkhead is designed to restrict the passage of smoke and flames for a minimum of 30 minutes, making it an essential component in fire safety for marine vessels. The classification indicates that the bulkhead has been tested and meets specific standards for fire resistance, providing a level of containment necessary to protect vital areas and allow time for evacuation or firefighting efforts.

Class B construction typically involves materials that can tolerate heat and resist ignition, thereby slowing the spread of fire and smoke from one compartment to another. This characteristic plays a crucial role in a ship’s fire safety strategy, as it helps to compartmentalize an area, potentially preventing a fire from affecting the entire vessel.

In contrast, other types of bulkheads, such as Class A, have a higher fire resistance than Class B, while Class C is not designed to provide any substantial fire resistance. Non-rated bulkheads lack any specific fire-resistance rating and provide no effective barrier against smoke or flames. Therefore, while all these types of bulkheads serve different purposes, a Class B bulkhead is specifically recognized for its capability to restrict smoke and flames effectively for at least half an hour.