Fire Prevention & Detection — Fire Safety Practice

Sample questions

1. 01What is the purpose of compartmentation in a building's fire safety strategy?

   • ATo divide a building into fire-resistant compartments that contain fire and smoke to the compartment of origin, limiting fire spread and protecting escape routes
   • BTo increase the number of escape routes available so that occupants always have more than one way out of the building
   • CTo divide a building into detection zones so that the fire alarm control panel can quickly indicate the area in which a fire has started to the attending crews
   • DTo separate the electrical wiring from the gas supply so that a fault in one service cannot affect the other

   Why: Compartmentation is the division of a building into fire-resistant compartments using fire-resisting walls, floors, and doors. Its purpose is to contain fire and smoke to the compartment of origin for a specified period, limiting fire spread, protecting means of escape, reducing the risk to occupants in other parts of the building, and reducing damage. The fire resistance period depends on the building type, height, and use — typically 30, 60, 90, or 120 minutes as specified in Approved Document B.

2. 02What is a fire door and what do the designations FD30 and FD60 mean?

   • AA fire door is a self-closing door — FD30 means that it closes within 30 seconds of release and FD60 within 60 seconds
   • BA fire door is a door rated by leaf width — FD30 is 30 inches wide and FD60 is 60 inches wide as installed
   • CA fire door is a door assembly designed to resist fire for a specified period — FD30 resists fire for 30 minutes and FD60 for 60 minutes
   • DA fire door is a door rated by cost — FD30 and FD60 indicate the manufacturer's grade of construction

   Why: A fire door is a complete assembly (door leaf, frame, intumescent seals, smoke seals, self-closer, and ironmongery) designed and tested to resist fire for a specified period. FD30 indicates 30 minutes of fire resistance, FD60 indicates 60 minutes, FD90 indicates 90 minutes, and FD120 indicates 120 minutes. The 'S' suffix (e.g., FD30S) indicates the door also provides smoke resistance. Fire doors are a critical element of compartmentation and must be maintained in good working condition with all components intact.

3. 03What is 'fire stopping' and why is it important?

   • AThe sealing of gaps and openings in fire-resisting walls, floors, and ceilings (where services such as cables, pipes, and ducts pass through) to maintain the integrity of the fire compartment
   • BThe fitting of self-closing devices to fire doors and shutters so that they close automatically when the fire alarm sounds
   • CThe shutting down of a fire by isolating the fuel, the oxygen or the source of heat that is feeding it, so that combustion cannot be sustained in the compartment any longer
   • DThe application of fire-retardant paint to combustible wall and ceiling linings in order to slow the spread of flame

   Why: Fire stopping is the sealing of gaps, joints, and openings in fire-resisting construction elements where building services (cables, pipes, ventilation ducts, cable trays) penetrate through fire-resisting walls, floors, and ceilings. Without proper fire stopping, these penetrations create pathways for fire and smoke to spread between compartments, potentially bypassing hours of fire resistance. Fire stopping materials include intumescent sealants, fire pillows, fire batts, and proprietary penetration seal systems, all of which must be installed and tested to the appropriate standard.