46 CFR § 72.0510  Type, location, and construction of fire control bulkheads and decks.
(a) The hull, structural bulkheads, decks, and deckhouses shall be constructed of steel or other equivalent metal construction of appropriate scantlings.
(b) The hull, superstructure, and deck houses shall be subdivided by suitable structural steel or other equivalent metal bulkheads into main vertical zones, the mean length of which shall not, in general, exceed 131 feet on any one deck. Where practicable, the main vertical zone bulkheads shall be kept in a single vertical plane. However, on vessels designed for special purposes, such as automobile or railroad car ferries, where the installation of such bulkheads would defeat the purpose for which the vessel is intended, equivalent means for controlling and limiting a fire may be substituted if specifically approved by the Commandant.
(c) All bulkheads and decks shall be classed as A60, A30, A15, A0, B15, B0, or C, depending upon the type of space on each side of the bulkhead or above and below the deck.
(1) Bulkheads or decks of the “A” Class shall be composed of steel or equivalent metal construction, suitably stiffened and made intact with the main structure of the vessel, such as shell, structural bulkheads, and decks. They shall be so constructed that, if subjected to the standard fire test, they would be capable of preventing the passage of smoke and flame for 1 hour. In addition, they shall be so insulated with approved structural insulation, bulkhead panels, or deck covering that the average temperatures on the unexposed side would not rise more than 250 °F. above the original temperature, nor would the temperature at any one point, including any joint, rise more than 325 °F. above the original temperature, within the time listed below:
Class A60  60 minutes. 

Class A30  30 minutes. 
Class A15  15 minutes. 
Class A0  0 minutes (i.e., no insulation requirements). 
(2) Bulkheads of the “B” Class shall be constructed with approved incombustible materials and made intact from deck to deck (or to ceiling as provided in paragraph (h) of this section) and to shell or other boundaries. They shall be so constructed that, if subjected to the standard fire test, they would be capable of preventing the passage of flame for 1/2 hour. In addition, their insulation value shall be such that the average temperature of the unexposed side would not rise more than 250 °F. above the original temperature, nor would the temperature at any one point, including any joint, rise more than 405 °F. above the original temperature within the time listed below:
Class B15  15 minutes. 

Class B0  0 minutes (i.e., no insulation requirements). 
(3) Class C bulkheads or decks shall be constructed of approved incombustible materials, but need meet no requirements relative to the passage of flame nor the limiting of temperature rise.
(d) The minimum requirements for the bulkheads between the various spaces, where such bulkheads form the boundaries of main vertical zones, shall be as noted in table 72.0510(d).
(e) The minimum requirements for the bulkheads between the various spaces, where such bulkheads do not form the boundaries of main vertical zones, shall be as noted in table 72.0510(e).
(f) The minimum requirements for the decks between the various spaces, where such decks form the boundaries of stepped main vertical zones, shall be as noted in table 72.0510(f).
(g) The minimum requirements for the decks between the various spaces, where such decks do not form the boundaries of stepped main vertical zones, shall be as noted in table 72.0510(g).
Table 72.0510(d)  Bulkheads  Main Vertical Zone




Control stations  Stairway and elevator enclosures  Corridors  Life boat embarkation or lowering stations  Staterooms and all public spaces with incombustible veneers and trim and fire resistant furnishings  Staterooms and public spaces of 500 square feet or less with combustible furnishings and isolated storerooms  Public spaces over 500 square feet with combustible furnishings  Washrooms toilet spaces, and isolated pantries with incombustible fittings  Galley, main pantries, storerooms, and workshops  Machinery spaces  Dry cargo spaces  Fuel and water tanks and voids  Open decks and enclosed promenades (not safety areas)  


Control stations  1  A60  A15  A15  A0  A30  A60  A60  A0  A60  A60  A60  A0  A0 
Stairway and elevator enclosures  2  A0  A0  A0  A0  A60  A60  A0  A60  A60  A60  A0  A0  
Corridors  3  A0  A0  A0  A0  A0  A0  A0  A0  A0  A0  A0  
Lifeboat embarkation or lowering stations  4  C  A0  A0  A0  A0  A0  A0  A0  A0  C  
Staterooms and all public spaces with incombustible veneers and trim and fire resistant furnishings  5  A15  A15  A15  A0  A30  A30  A30  A0  A0  
Staterooms and public spaces of 500 square feet or less with combustible furnishings, and isolated storerooms  6  A60  A60  A0  A60  A60  A60  A0  A0  
Public spaces over 500 square feet with combustible furnishings  7  A60  A0  A60  A60  A60  A0  A0  
Washrooms, toilet spaces, and isolated pantries with incombustible fittings  8  A0  A0  A0  A0  A0  A0  
Galleys, main pantries, storerooms, and workshops  9  A0  A0  A0  A0  A0  
Machinery spaces  10  A0  A0  A0  A0  
Dry cargo spaces  11  A0  A0  A0  
Fuel and water tanks and voids  12  A0  A0  
Open decks and enclosed promenades (not safety areas)  13  C 
Table 72.0510(e)  Bulkheads  Not Main Vertical Zones




Control stations  Stairway and elevator enclosures  Corridors  Life boat embarkation or lowering stations  Staterooms and all public spaces with incombustible veneers and trim and fire resistant furnishings  Staterooms and public spaces of 500 square feet or less with combustible furnishings and isolated storerooms  Public spaces over 500 square feet with combustible furnishings  Washrooms toilet spaces, and isolated pantries with incombustible fittings  Galley, main pantries, storerooms, and workshops  Machinery spaces  Dry cargo spaces  Fuel and water tanks and voids  Open decks and enclosed promenades (not safety areas)  


Control stations  1  B0  A0  A0  A0  A15  A60  A60  A0  A60  A60  A60  A0  A0 
Stairway and elevator enclosures  2  C  A0  A0  A0  A60  A60  A0  A60  A60  A60  A0  A0  
Corridors  3  C  A0  B0  B0  A0  B0  A0  A0  A0  A0  A0  
Lifeboat embarkation or lowering stations  4  C  A0  A0  A0  A0  A0  A0  A0  A0  C  
Staterooms and all public spaces with incombustible veneers and trim and fireresistant furnishings  5  B0  B15  A15  B0  A15  A15  A15  A0  A0  
Staterooms and public spaces of 500 square feet or less with combustible furnishings, and isolated storerooms  6  B15  A30  B0  A60  A60  A60  A0  A0  
Public spaces over 500 square feet with combustible furnishings  7  A60  B0  A60  A60  A60  A0  A0  
Washrooms, toilet spaces and isolated pantries with incombustible fittings  8  C  A0  A0  A0  A0  A0  
Galleys, main pantries, storerooms, and workshops  9  C ^{1}  A0  A0  A0  A0  
Machinery spaces  10  C  A0  A0  A0  
Dry cargo spaces  11  A0  A0  A0  
Fuel and water tanks and voids  12  A0  A0  
Open decks and enclosed promenades (not safety areas)  13  C 
1 Class C bulkheads may be used between two similar spaces, such as between two similar storerooms. However, a Class A0 bulkhead shall be used between dissimilar spaces, such as a storeroom and a dissimilar workshop.
Table 72.0510(f)  Decks  Main Vertical Zones




Control stations  Stairway and elevator enclosures  Corridors  Life boat embarkation or lowering stations  Staterooms and all public spaces with incombustible veneers and trim and fire resistant furnishings  Staterooms and public spaces of 500 square feet or less with combustible furnishings and isolated storerooms  Public spaces over 500 square feet with combustible furnishings  Washrooms toilet spaces, and isolated pantries with incombustible fittings  Galley, main pantries, storerooms, and workshops  Machinery spaces  Dry cargo spaces  Fuel and water tanks and voids  Open decks and enclosed promenades (not safety areas)  


Control stations  1  A60  A60  A30  A0  A15  A60  A60  A0  A0  A0  A0  A0  A0 
Stairway and elevator enclosures  2  A15  A0  A0  A0  A0  A0  A0  A0  A0  A0  A0  A0  A0 
Corridors  3  A30  A0  A0  A0  A0  A0  A15  A0  A0  A0  A0  A0  A0 
Lifeboat embarkation or lowering stations  4  A0  A0  A0  C  A0  A0  A0  A0  A0  A0  A0  A0  C 
Staterooms and all public spaces with incombustible veneers and trim and fire resistant furnishings  5  A30  A30  A15  A0  A15  A15  A30  A0  A0  A0  A0  A0  A0 
Staterooms and public spaces of 500 square feet or less with combustible furnishings, and isolated storerooms  6  A60  A60  A30  A15  A15  A60  A60  A0  A0  A0  A0  A0  A0 
Public spaces over 500 square feet with combustible furnishings  7  A60  A60  A60  A30  A30  A60  A60  A0  A0  A0  A0  A0  A0 
Washrooms, toilet spaces, and isolated pantries with incombustible fittings  8  A0  A0  A0  A0  A0  A0  A0  A0  A0  A0  A0  A0  A0 
Galleys, main pantries, storerooms, and workshops  9  A60  A60  A60  A30  A30  A60  A60  A0  A0  A0  A0  A0  A0 
Machinery spaces  10  A60  A60  A60  A30  A30  A60  A60  A0  A0  A0  A0  A0  A0 
Dry cargo spaces  11  A60  A60  A60  A30  A30  A60  A60  A0  A0  A0  A0  A0  A0 
Fuel and water tanks and voids  12  A0  A0  A0  A0  A0  A0  A0  A0  A0  A0  A0  A0  A0 
Open decks and enclosed promenades (not safety areas)  13  A0  A0  A0  C  A0  A0  A0  A0  A0  A0  A0  A0  C 
Table 72.0510(g)  Decks  Not Main Vertical Zones




Control stations  Stairway and elevator enclosures  Corridors  Life boat embarkation or lowering stations  Staterooms and all public spaces with incombustible veneers and trim and fire resistant furnishings  Staterooms and public spaces of 500 square feet or less with combustible furnishings and isolated storerooms  Public spaces over 500 square feet with combustible furnishings  Washrooms toilet spaces, and isolated pantries with incombustible fittings  Galley, main pantries, storerooms, and workshops  Machinery spaces  Dry cargo spaces  Fuel and water tanks and voids  Open decks and enclosed promenades (not safety areas)  


Control stations  1  A30  A30  A15  A0  A0  A15  A30  A0  A0  A0  A0  A0  A0 
Stairway and elevator enclosures  2  A0  C  A0  A0  A0  A0  A0  A0  A0  A0  A0  A0  A0 
Corridors  3  A15  A0  A0  A0  A0  A0  A15  A0  A0  A0  A0  A0  A0 
Lifeboat embarkation or lowering stations  4  A0  A0  A0  C  A0  A0  A0  A0  A0  A0  A0  A0  C 
Staterooms and all public spaces with incombustible veneers and trim and fire resistant furnishings  5  A15  A15  A0  A0  A0  A0  A15  A0  A0  A0  A0  A0  A0 
Staterooms and public spaces of 500 square feet or less with combustible furnishings and isolated storerooms  6  A60  A60  A30  A15  A0  A30  A60  A0  A0  A0  A0  A0  A0 
Public spaces over 500 square feet with combustible furnishings  7  A60  A60  A60  A30  A15  A60  A60  A0  A0  A0  A0  A0  A0 
Washrooms, toilet spaces, and isolated pantries with incombustible fittings  8  A0  A0  A0  A0  A0  A0  A0  A0  A0  A0  A0  A0  A0 
Galleys, main pantries, storerooms, and workshops  9  A60  A60  A60  A30  A15  A60  A60  A0  A0  A0  A0  A0  A0 
Machinery spaces  10  A60  A60  A60  A30  A15  A60  A60  A0  A0  C  A0  A0  A0 
Dry cargo spaces  11  A60  A60  A60  A30  A15  A60  A60  A0  A0  A0  A0  A0  A0 
Fuel and water tanks and voids  12  A0  A0  A0  A0  A0  A0  A0  A0  A0  A0  A0  A0  A0 
Open decks and enclosed promenades (not safety areas)  13  A0  A0  A0  C  A0  A0  A0  A0  A0  A0  A0  A0  C 
(h) Where ceilings or linings are fitted, “B” Class bulkheads, with the exception of those forming passageways, may stop at the ceiling or lining and need not continue to the deck or shell, provided the ceiling and/or lining is erected as indicated in paragraph (j) of this section. However, draft stops meeting at least Class B0 requirements shall be fitted not more than 45 feet apart between the ceiling or lining and the deck or shell. The space behind the linings of stairways and similar trunks shall have similar draft stops at each deck.
(i) Where Class B15 bulkhead panels are required to go beyond the ceiling to the deck above, or beyond the lining to the shell, the portion of the bulkhead panel within the void space need only meet B0 requirements.
(j) Where “B” Class panels are used, all four edges of the panel shall be retained by continuous steel or equivalent metal flanges on both sides of the panel offering at least 3/4 inch coverage. The top and bottom flanges shall be so attached to the structural decks above and below so as to support and restrain the panels in the event of fire. Other methods of construction may be specifically approved by the Commandant if determined to be equivalent.
(k) Any sheathing, furring, or holding pieces incidental to the securing of structural insulation shall be of approved incombustible materials.
(l) Where linings or bulkhead panels are framed away from the shell or structural bulkheads, the deck within the void space so formed need only meet Class A0 requirements.
(m) Decks within accommodation spaces and inside safety areas may have an overlay for leveling or finishing purposes which need not meet the requirements for an approved deck covering. Such an overlay will not be considered as giving any insulating value and may not in general exceed 3/8 of an inch in thickness. Greater thicknesses may be specifically approved by the Commandant for specific locations.
(n) Rugs and carpets may be used in addition to any deck covering or overlay installed. Rugs and carpets used in stairways or corridors shall be of wool, or other materials having equivalent fireresistive qualities.
(o) Decking within surgical operating rooms shall be of a type which is acceptably conductive to prevent accumulation of dangerous electrostatic charges, and shall be in general agreement with “Code for Flammable Anesthetics” of issue in effect at the time the construction or alteration of the vessel is contracted for, published by the National Fire Protection Association, 1 Batterymarch Park, Quincy, MA 02269.
(p) Decks in washrooms and toilet spaces, service, cargo, and machinery spaces, open decks, exterior safety areas, and enclosed promenades may have an overlay in any thickness. This overlay need not meet the requirements for an approved deck covering.
The following state regulations pages link to this page.