Module 19: Structural Fire Protection

Question 1

What does proper structural design impact regarding structural fire protection?

Answer 1

• Minimize loss of life
• Minimize injury
• Minimize loss of assets
• Fire prevention to reduce probability

Question 2

Basic Principles of Fire Protection

Answer 2

1. Division of ship into vertical zones through the use of thermal and structural boundaries having specific fire endurance
2. Separation of certain spaces (high risk areas) from the remainder of the ship through the use of thermal and structural boundaries having specific fire endurance
3. Protect escape/ access routes
4. Restrict the use of combustible materials

Question 3

Extra Principles

Answer 3

1. Detect smoke and fire at early stage and in zone of origin
2. Contain the fire in the space of origin and extinguish rapidly
3. Install adequate quantity and type of fire extinguishing equipment
4. Minimize ignition of flammable cargo vapour
5. Good procedures and management practices
6. Education and training

Question 4

Class A Divisions

Answer 4

1. Constructed of steel or equivalent material
2. Suitably stiffened
3. Insulated with approved non-combustible materials such that the average temperature is less than 140C and any one point does not exceed 180C above the original temperature
4. Prevent the passage of smoke and flame for 60 minutes

Question 5

Class A Subdivisions

Answer 5

Class A-60: provide suitable heat protection for 60 minutes
Class A-30: provide suitable heat protection for 30 minutes
Class A-15: provide suitable heat protection for 15 minutes
Class A-0: no requirement for time

Question 6

Class B Divisions

Answer 6

1. Constructed of approved non-combustible material
2. Insulated with approved non-combustible materials such that the average temperature is less than 140C and any one point does not exceed 225C above the original temperature
3. Prevent the passage of flame for 30 minutes

Question 7

Class B Subdivisions

Answer 7

Class B-15: provide suitable heat protection for 15 minutes
Class B-0: no requirement for time

Question 8

Main Vertical Zones

Answer 8

Main vertical zones are used as structural fire protection. In special cases, an equivalent horizontal separation may be permitted. The maximum length between separations is no more than 40 m.

Question 9

Non-Combustible Material

Answer 9

Does not burn or give off flammable vapor when heated to 750C. Eg: sheet glass, uncoated glass fibers, glass fabric, block glass, clay, ceramics, all metals (except magnesium and magnesium alloys), magnesite concretes and gypsum.

Question 10

Combustible Material

Answer 10

Any other material that does not satisfy the above criteria.
In passenger ships, total volume of combustible material in any accommodation and service space should not exceed a volume equivalent of 2.5mm thick veneer on combined area of walls and ceilings.
In cargo ships, accommodation and service spaces should not exceed 2mm veneer except in corridors and stairways where it must not exceed 1.5 mm

Question 11

Steel or Equivalent

Answer 11

Steel and steel alloy as well as any non-combustible material which by itself or with suitable insulation has structural and fire integrity properties equivalent to steel

Question 12

Standard Fire Test

Answer 12

Specimens of bulkheads or decks are exposed to a furnace temperature corresponding to a time/temperature curve

Question 13

Surface Flame Spread

Answer 13

Low flame spread will resist the propagation of flame. Spread may be controlled through the use of intumescent coatings. These coatings create a partial fire barrier when heated, creating passive fire resistance

Question 14

Low Flame Spread - Passenger Ships

Answer 14

• Exposed surfaces in corridors and stairway enclosures
• Exposed surfaces in all accommodation spaces, service spaces, and control stations
• Surfaces in concealed or inaccessible spaces in accommodation spaces, service spaces, and control rooms.
  Does not apply to furniture, furnishings, machinery, or similar unless otherwise specified.
  Ceiling light diffusers may be fitted on ceiling mounted light fittings as long as enclosed in steel housing - total surface area of plastic < 20% of total ceiling area

Question 15

Low Flame Spread - Cargo Ships and Tankers

Answer 15

• Exposed surfaces in corridors and stairway enclosures
• Exposed surfaces in all accommodation spaces, service spaces, and control stations
• Surfaces in concealed or inaccessible spaces in accommodation spaces, service spaces, and control rooms.
  Does not apply to furniture, furnishings, machinery, or si
  Ceiling light diffusers may be fitted on ceiling mounted light fittings as long as enclosed in steel housing - total surface area of plastic < 20% of total ceiling area

Question 16

Low Flame and Low Smoke Generation - Cargo Ships

Answer 16

Applied on exposed surfaces in corridors and stairway enclosures; exposed surfaces in accommodation spaces, service spaces, and control spaces; concealed or inaccessible spaces in accommodation spaces, service spaces and control rooms.

Question 17

Low Flame and Low Smoke Generation - Passenger Ships

Answer 17

Applied on exposed surfaces in corridors and stairway enclosures; exposed surfaces in accommodation spaces, service spaces, and control spaces; concealed or inaccessible spaces in accommodation spaces, service spaces and control rooms.

Question 18

Accommodation Spaces

Answer 18

Accommodation spaces include :
- Public areas (dining rooms, lounges, libraries and similar enclosed spaces),
- Lobbies, corridors, public washrooms, game rooms, and crew cabins.

Question 19

High Risk Service Spaces

Answer 19

High risk service spaces include galleys, pantries containing cooking appliances, paint rooms, lockers and storerooms having an area of 2m2 or larger, and workshops (other than a workshop forming part of a machinery space).

Question 20

Low Risk Service Areas

Answer 20

Low risk service spaces include lockers and storerooms having an area smaller than 2m2, as well as drying and laundry rooms.

Question 21

Cargo Spaces

Answer 21

Cargo spaces include any space used for cargo (including cargo oil tanks and trunking leading to and from such spaces). Special care is taken to ensure fire and watertight integrity of roll-on/ roll-off vessels due to the fact that cargo spaces are not usually subdivided and extend a substantial length or the entire length of the vessel.

Question 22

Machinery Spaces - “A”

Answer 22

Contain internal combustion machinery (over 375 kW), oil-fired boilers or fuel treatment/preparation systems. Includes trunking to and from these spaces.

Question 23

Machinery Spaces - General

Answer 23

All category A machinery spaces PLUS
- Propelling units
- Auxiliary spaces including emergency machinery
- Oil filling stations
- Refrigeration equipment spaces
- Air conditioning and ventilation equipment spaces
- Steering gear spaces
- Stabilizing unit spaces
- All trunking to and from these spaces

Question 24

Control Spaces

Answer 24

• Emergency sources of power and lighting (including battery rooms)
• Ship’s radio equipment
• Main navigation equipment
• Wheelhouse and chart rooms
• Centralized emergency public address system and equipment
• Propulsion controls (when outside the propelling machinery spaces)
• Smother gas cylinders and related equipment
• Fire control and recording equipment
• Sprinkler and water deluge system controls
• Emergency fire pumps
  PLUS trunking to and from these spaces

Question 25

Ceilings

Answer 25

Ceilings refer to horizontal divisions fitted near the deckhead of a space for the purpose of decoration, acoustics, and fire protection. Ceilings are supported by an approved system of brackets attached to the deckhead.

Question 26

Liners

Answer 26

Liners refer to vertical divisions covering bulkheads and are used for decorative purposes, acoustical control, and fire protection. Generally these are in the form of pre-fabricated panels, having a durable exterior surface. Liners are supported by an approved system of brackets attached to the bulkhead. Ceilings and liners are often panels made of non-combustible binder board or steel-faced mineral wool.

Question 27

Stairway

Answer 27

Stairways leading from deck to deck must be provided with the appropriate class of fire protection in order to reduce the vertical spread from level to level. These areas typically act as chimneys and if not properly rated can result in fire on several decks in a very short period of time. These stairways provide the primary means of escape from the access to a fire area. A stairway cuts through one deck and has a self-closing fire door at one level only.

Question 28

Stair Tower

Answer 28

A stair tower cuts two or more decks and has self-closing fire doors at every level.

Question 30

Fire Protection Plan Inclusions

Answer 30

- Fire zone plans - Insulation details - Bulkhead, ceiling, liners, and draft stop details - Deck covering details - Ventilation system details - List of doors - Penetration details

Question 31

Fire Zone Plan

Answer 31

The fire zone plan is not to be confused with any tactical firefighting plans used to guide the ship’s officers and crew in the event of a fire-related emergency. This plan is strictly to allow each area of the vessel to be identifiable in regards to the level of fire protection offered for construction and repair purposes.

Question 32

Draft Stops

Answer 32

Draft stops are non-combustible divisions that are placed between a ceiling or a liner and the ship’s structure at intervals of not more than 14 m. They are used to prevent rapid spread of smoke and flame through these spaces.

Question 33

Liners and Ceilings

Answer 33

Fitting of liners and ceilings introduces spaces at the ship’s structure behind the liner or ceiling. These spaces act as conduits for smoke and flame and could easily allow the passage of fire from one location to another. To stop or slow down the spread of fire, draft stops are installed at every deck, as well as both longitudinally and transversely at a maximum spacing of 14 m.

Question 34

Penetration Details

Answer 34

Fire rated bulkheads are penetrated by pipes, electrical wiring, ventilation ducting and personnel doors. Any time these penetrations occur, the fire integrity of the bulkhead must be maintained. Pipes and cables passing through an insulated “A” Class bulkhead are to be suitably insulated to the same standard as the bulkhead. If the pipe or cable penetration is near a tank top or outer shell plating and below the level of the boundary insulation, it does not require insulation. However, insulation may be required for cables that are heat sensitive. Pipes must be properly attached to the bulkhead and made of non-combustible material with a melting temperature of at least 100°C.

Question 35

Insulation Details

Question 36

Deck Covering Details

Answer 36

The insulation of decks for fire protection purposes can be accomplished by insulating the underside of the deck plating or by applying an approved fire rated deck covering on the upper size of the deck.

Question 37

Ventilation System Details

Question 39

Fire Rated Door

Question 40

Means of Escape

Question 41

Miscellaneous Requirements

Answer 41

- Materials which have been approved only for use as an insulation for “A” Class bulkheads should not be used as an insulation for “A” Class decks and vice versa. - Class “A” bulkheads are built from steel or a material equivalent in strength and fire resistance. - Class “A” bulkheads above the bulkhead deck should be in line vertically with the bulkheads below the bulkhead deck. - Bulkheads separating accommodations from cargo holds or machinery spaces are to be of a class “A” rating. - Control stations, due to their important nature, are enclosed in a class “A” structure. - Other bulkheads within the main vertical divisions are to be class “A”, “B”, or “C” standard depending upon the risk and consequences of a fire. - Machinery space skylights should be operable from outside the space and should be provided with steel covers. - Individuals on board ship are tasked with the job of closing dampers and checking equipment operation during a general/fire alarm situation. All personnel should verify their fire and boat locations and duties at the earliest possible time upon joining a ship. - It is policy in many companies to assign an officer to familiarize newcomers to their jobs, positions, and the safety equipment.

Question 42

Basic Principles of Structural Fire Protection

Answer 42

- Restriction on the use of combustible materials - Installation of adequate quantity and type of fire extinguishing equipment - Division of the ship into main vertical zones by the use of thermal and structural boundaries - Protection of escape or access routes.

Question 43

Structural Fire Protection Relies on

Answer 43

Structural fire protection relies on proper design of the ship's structure to minimise the probability of a major fire and the resulting loss of life