Fire Safety Flashcards
After sustaining fire damage you discover that cracks have appeared in the brickwork, what could this be?
- The bricks have heated causing them to expand and then contracted when they have cooled.
- This movement could cause cracking.
- Also if it is a framed building then the frame of the structure could have been weakened by the fire causing movement which would cause the brickwork to crack.
What items would you consider when preparing a fire insurance valuation or a building reinstatement valuation?
- Debris removal.
- Site clearance.
- Building foundations.
- Erection of the replacement building.
- Installation of electrical & mechanical services.
- Commissioning and professional fees.
In respect of Fire Insurance Valuations, what is a day one assessment?
- The current valuation will represent the reinstatement cost at today’s date or day one of the insurance policy.
- During the year, building reinstatement costs may rise by an inflationary amount, therefore under a standard policy of insurance you will need to estimate the likely inflation during the year and add this to your valuation otherwise if a loss occurs on the final day of the policy year, your sum insured may not be adequate and insurers will apply averages to their payments.
- Under the day one basis of insurance, insurers provide insurance up to a fixed percentage above your day one valuation, usually 15%. This should ensure that the sum insured is adequate when a loss occurs.
- The only condition is that your declared day one valuation must accurately represent the reinstatement cost at day one of the policy otherwise averages will again apply.
- This policy does carry an added risk premium than standard cover but dispenses with the problem of guessing inflation levels that will apply during the next 12 months.
What conditions are needed for a fire to start in a building?
- Fire occurs as a result of a series of very rapid chemical reactions between a fuel source and oxygen that releases heat and light.
- For combustion to occur, oxygen, heat and a fuel source must all be present; this is the ‘fire triangle’.
- Flames are the visible manifestation of combustion.
- The ‘flash point’ is the temperature to which a fuel has to be heated for the gases given off to flash when an ignition source is applied.
- The ‘fire point’ is the temperature to which a fuel has to be heated for the vapours given off by the fuel to sustain ignition.
- The ‘spontaneous ignition temperature’ is the temperature at which these vapours ignite spontaneously without the application of an external flame. Once ignition has begun and the vapours ignited, flames will in turn heat the fuel and increase the rate of production of flammable vapours.
How might a fire start in a building?
- According to the National Fire Protection Association (NFPA), the five most common causes of fires in commercial buildings are:-
o Cooking equipment.
o Heating equipment.
o Electrical and lighting equipment.
o Smoking materials (cigarettes).
o Intentional fire setting.
How do fires spread in buildings?
- Fire passes through a series of stages from the moment of ignition to the time at which all combustible materials are alight.
- A critical stage occurs when the flames reach the ceiling. The radiant heat transferred back to the surface of the fuel is dramatically increased. This usually occurs when the temperature at the ceiling has reached about 550°C.
- The remaining combustible materials will then rapidly reach their fire points and ignite within 3-4 seconds, this sudden transition is called a flashover.
- If there is inadequate ventilation during the growth period, a fire may fail to flashover. It may die out or continue to smoulder. This can be extremely hazardous as a new supply of oxygen may be ‘supplied’, for example, by a door or window being opened.
- During the stable phase which follows flashover, flaming occurs throughout the enclosed space. This is when the highest temperatures are reached. The fire resistance of the elements that form the enclosure will have to take account of the maximum temperatures likely to be reached as well as the length of time they are likely to be sustained.
How can fires be contained by the structure or layout of a building?
- The spread of fire can be restricted by sub-dividing buildings into a number of discrete compartments.
- These fire compartments are separated from one another by compartment walls and compartment floors made of a fire-resisting construction which restrict the spread of fire. These can take the form of:-
o Fire Cavity Barriers in ceiling and floor voids.
o Fire rated partitions.
o Fire rated door fittings with fire seals.
How is the structure of a building protected from fires?
- Intumescent coatings can be used to protect the structure of buildings from fire damage. When the coating is exposed to high temperatures, multiple chemical components inside the intumescent coating react. This causes the coating to increase in density, creating a fireproof layer so no oxygen can reach the surface of the structure.
- Compartmentation methods such as fire walls, doors, and cavity barriers can also be used. Cavity barriers inhibit the spread of smoke through open spaces in roofs and between floors. These barriers can be made from a variety of materials, such as concrete, gypsum or masonry.
- Firestopping can be used to remediate the structure from being compromised due to the install of service penetrations. Small holes drilled into the structure or through fire compartment walls can contribute towards the spread of fire. These gaps can be fire stopped to further protect the structure from fire damage.
What methods are available to ensure the safe escape of a buildings occupants?
Fire Exits
* The Regulatory Reform (Fire Safety) Order, charges the responsible person(s) in control of non-domestic premises with the safety of everyone, whether employed in or visiting the building.
* Under Article 14 of the RRFSO, this duty of care includes ensuring that “routes to emergency exits from premises and the exits themselves are kept clear at all times” and that these “emergency routes and exits must lead as directly as possible to a place of safety”.
Places of Relative Safety
* It is often necessary to devise a temporary place of safety, such as when evacuating high buildings. This may be defined as a place of comparative safety and includes any place that puts an effective barrier (normally 30 minutes’ fire resistance) between the person escaping and the fire. Examples are as follows:
o A storey exit into a protected stairway or the lobby of a lobby approach stairway.
o A door in a compartment wall or separating wall leading to an alternative exit.
o A door that leads directly to a protected stair or a final exit via a protected corridor.
Place of Ultimate Safety
* Ideally, this should be in the open air, where unrestricted dispersal away from the building can be achieved.
* Escape routes should never discharge finally into enclosed areas or yards, unless the dispersal area is large enough to permit all the occupants to proceed to a safe distance. (Note: a safe distance equates to at least the height of the building, measured along the ground).
* Total dispersal in the open air therefore constitutes ultimate safety.
* When inspecting any building, it is important always to follow the escape route to its ultimate place of safety.
* The final exits on these escape routes must have sufficient capacity to ensure the swift and safe evacuation of people from the building in an emergency situation.
What are the responsibilities of key duty holders such as occupiers and management undertaking risk assessments?
- You are responsible for fire safety in a business or other non-domestic premises if you’re:
o An employer.
o The owner.
o The landlord.
o An occupier.
o Anyone else with control of the premises, for example a facilities manager, building manager, managing agent or risk assessor. - If there is more than one responsible person, you have to work together to meet your responsibilities.
- The Fire Safety Order also applies if you have paying guests, for example if you run a bed and breakfast, guesthouse or let a self-catering property.
- As the responsible person you must:-
o Carry out a fire risk assessment of the premises and review it regularly.
o Tell staff or their representatives about the risks you’ve identified.
o Put in place and maintain appropriate fire safety measures.
o Plan for an emergency.
o Provide staff information, fire safety instruction and training.
What systems are available to protect buildings and occupiers from the outbreak of fires?
- Fire and smoke detection (sounders and beacons).
- Fire Sprinkler Systems.
- Inert Gas Suppression Systems (common in server rooms & data centres).
