46 C.F.R. § 72.05-10
(c) All bulkheads and decks shall be classed as A-60, A-30, A-15, A-0, B-15, B-0, 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 A-60 | 60 minutes. |
| Class A-30 | 30 minutes. |
| Class A-15 | 15 minutes. |
| Class A-0 | 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 B-15 | 15 minutes. |
| Class B-0 | 0 minutes (i.e., no insulation requirements). |
(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 72.05-10(g).
| ADJACENT TO | THIS SPACE: | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 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) | ||
| THIS SPACE: | ||||||||||||||
| Control stations | 1 | A-60 | A-15 | A-15 | A-0 | A-30 | A-60 | A-60 | A-0 | A-60 | A-60 | A-60 | A-0 | A-0 |
| Stairway and elevator enclosures | 2 | A-0 | A-0 | A-0 | A-0 | A-60 | A-60 | A-0 | A-60 | A-60 | A-60 | A-0 | A-0 | |
| Corridors | 3 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | ||
| Lifeboat embarkation or lowering stations | 4 | C | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | C | |||
| Staterooms and all public spaces with incombustible veneers and trim and fire resistant furnishings | 5 | A-15 | A-15 | A-15 | A-0 | A-30 | A-30 | A-30 | A-0 | A-0 | ||||
| Staterooms and public spaces of 500 square feet or less with combustible furnishings, and isolated storerooms | 6 | A-60 | A-60 | A-0 | A-60 | A-60 | A-60 | A-0 | A-0 | |||||
| Public spaces over 500 square feet with combustible furnishings | 7 | A-60 | A-0 | A-60 | A-60 | A-60 | A-0 | A-0 | ||||||
| Washrooms, toilet spaces, and isolated pantries with incombustible fittings | 8 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | |||||||
| Galleys, main pantries, storerooms, and workshops | 9 | A-0 | A-0 | A-0 | A-0 | A-0 | ||||||||
| Machinery spaces | 10 | A-0 | A-0 | A-0 | A-0 | |||||||||
| Dry cargo spaces | 11 | A-0 | A-0 | A-0 | ||||||||||
| Fuel and water tanks and voids | 12 | A-0 | A-0 | |||||||||||
| Open decks and enclosed promenades (not safety areas) | 13 | C |
| ADJACENT TO | THIS SPACE: | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 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) | ||
| THIS SPACE: | ||||||||||||||
| Control stations | 1 | B-0 | A-0 | A-0 | A-0 | A-15 | A-60 | A-60 | A-0 | A-60 | A-60 | A-60 | A-0 | A-0 |
| Stairway and elevator enclosures | 2 | C | A-0 | A-0 | A-0 | A-60 | A-60 | A-0 | A-60 | A-60 | A-60 | A-0 | A-0 | |
| Corridors | 3 | C | A-0 | B-0 | B-0 | A-0 | B-0 | A-0 | A-0 | A-0 | A-0 | A-0 | ||
| Lifeboat embarkation or lowering stations | 4 | C | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | C | |||
| Staterooms and all public spaces with incombustible veneers and trim and fire-resistant furnishings | 5 | B-0 | B-15 | A-15 | B-0 | A-15 | A-15 | A-15 | A-0 | A-0 | ||||
| Staterooms and public spaces of 500 square feet or less with combustible furnishings, and isolated storerooms | 6 | B-15 | A-30 | B-0 | A-60 | A-60 | A-60 | A-0 | A-0 | |||||
| Public spaces over 500 square feet with combustible furnishings | 7 | A-60 | B-0 | A-60 | A-60 | A-60 | A-0 | A-0 | ||||||
| Washrooms, toilet spaces and isolated pantries with incombustible fittings | 8 | C | A-0 | A-0 | A-0 | A-0 | A-0 | |||||||
| Galleys, main pantries, storerooms, and workshops | 9 | C 1 | A-0 | A-0 | A-0 | A-0 | ||||||||
| Machinery spaces | 10 | C | A-0 | A-0 | A-0 | |||||||||
| Dry cargo spaces | 11 | A-0 | A-0 | A-0 | ||||||||||
| Fuel and water tanks and voids | 12 | A-0 | A-0 | |||||||||||
| 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 A-0 bulkhead shall be used between dissimilar spaces, such as a storeroom and a dissimilar workshop. |
| ADJACENT TO | THIS SPACE: | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 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) | ||
| THIS SPACE: | ||||||||||||||
| Control stations | 1 | A-60 | A-60 | A-30 | A-0 | A-15 | A-60 | A-60 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 |
| Stairway and elevator enclosures | 2 | A-15 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 |
| Corridors | 3 | A-30 | A-0 | A-0 | A-0 | A-0 | A-0 | A-15 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 |
| Lifeboat embarkation or lowering stations | 4 | A-0 | A-0 | A-0 | C | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | C |
| Staterooms and all public spaces with incombustible veneers and trim and fire resistant furnishings | 5 | A-30 | A-30 | A-15 | A-0 | A-15 | A-15 | A-30 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 |
| Staterooms and public spaces of 500 square feet or less with combustible furnishings, and isolated storerooms | 6 | A-60 | A-60 | A-30 | A-15 | A-15 | A-60 | A-60 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 |
| Public spaces over 500 square feet with combustible furnishings | 7 | A-60 | A-60 | A-60 | A-30 | A-30 | A-60 | A-60 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 |
| Washrooms, toilet spaces, and isolated pantries with incombustible fittings | 8 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 |
| Galleys, main pantries, storerooms, and workshops | 9 | A-60 | A-60 | A-60 | A-30 | A-30 | A-60 | A-60 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 |
| Machinery spaces | 10 | A-60 | A-60 | A-60 | A-30 | A-30 | A-60 | A-60 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 |
| Dry cargo spaces | 11 | A-60 | A-60 | A-60 | A-30 | A-30 | A-60 | A-60 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 |
| Fuel and water tanks and voids | 12 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 |
| Open decks and enclosed promenades (not safety areas) | 13 | A-0 | A-0 | A-0 | C | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | C |
| ADJACENT TO | THIS SPACE: | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 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) | ||
| THIS SPACE: | ||||||||||||||
| Control stations | 1 | A-30 | A-30 | A-15 | A-0 | A-0 | A-15 | A-30 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 |
| Stairway and elevator enclosures | 2 | A-0 | C | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 |
| Corridors | 3 | A-15 | A-0 | A-0 | A-0 | A-0 | A-0 | A-15 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 |
| Lifeboat embarkation or lowering stations | 4 | A-0 | A-0 | A-0 | C | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | C |
| Staterooms and all public spaces with incombustible veneers and trim and fire resistant furnishings | 5 | A-15 | A-15 | A-0 | A-0 | A-0 | A-0 | A-15 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 |
| Staterooms and public spaces of 500 square feet or less with combustible furnishings and isolated storerooms | 6 | A-60 | A-60 | A-30 | A-15 | A-0 | A-30 | A-60 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 |
| Public spaces over 500 square feet with combustible furnishings | 7 | A-60 | A-60 | A-60 | A-30 | A-15 | A-60 | A-60 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 |
| Washrooms, toilet spaces, and isolated pantries with incombustible fittings | 8 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 |
| Galleys, main pantries, storerooms, and workshops | 9 | A-60 | A-60 | A-60 | A-30 | A-15 | A-60 | A-60 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 |
| Machinery spaces | 10 | A-60 | A-60 | A-60 | A-30 | A-15 | A-60 | A-60 | A-0 | A-0 | C | A-0 | A-0 | A-0 |
| Dry cargo spaces | 11 | A-60 | A-60 | A-60 | A-30 | A-15 | A-60 | A-60 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 |
| Fuel and water tanks and voids | 12 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 |
| Open decks and enclosed promenades (not safety areas) | 13 | A-0 | A-0 | A-0 | C | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | A-0 | C |
[CGFR 65-50, 30 FR 16903, Dec. 30, 1965, as amended by CGD 95-072, 60 FR 50463, Sept. 29, 1995; CGD 95-028, 62 FR 51204, Sept. 30, 1997]