Fire Safety Flashcards
How can you tell if timbers have been structurally affected by fire?
I would engage the services of a structural engineer as I do not believe I am competent enough to
make that decision. However, I would suggest that they would look at the extent of the damage how
much of the timber remains untouched by the fire and calculate whether the remaining good timber
can support the loadings imposed upon it.
After the fire, cracks appear in the brickwork, what could this be?
The bricks have heated causing them to expand and then contracted when they have been cooled.
This movement could cause cracking. Also if it is a framed building then the frame then 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 and site clearance, building foundations and cement floor base, erection of the
replacement building, installation of electrical & mechanical services, commissioning and professional
fees.
In respect to Fire Insurance Valuations, what is a day one assessment? Is it subject to
VAT?
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 average 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 average will again apply. This policy does
cost more 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 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 cooking equipment,
heating equipment, electrical and lighting equipment, smoking materials
(cigarettes), and 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.
For more information see: Understanding the factors affecting flashover of a
fire in modern buildings.
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?
Fire compartments
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 hinders the spread of fire.
Fire Cavity Barriers in ceiling void
Fire rated partitions
Fire rated door fittings with fire seals
How is the structure of a building protected from fires?
Intumescent coatings (When exposed to temperatures of up to 250°C,
multiple chemical components inside the intumescent coating will react. This
causes the coating to increase in density, creating a fireproof layer so no
oxygen can get to the steel)
Compartmentation (fire walls, doors, and cavity barriers. 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 (Sometimes when plumbers, electricians, and contractors work
on a building, they can inadvertently compromise structural fire protection
measures. Say an electrician drills holes and runs wires through a fire wall.
No matter how small this hole may be, the wall no longer offers effective fire
protection. Fire can penetrate the smallest gaps and ignite almost anything
that lies in its path. Therefore, these gaps must be filled as quickly as
possible, and by qualified firestopping contractors. This process is called
‘fireproofing
What methods are available to ensure the safe escape of a
buildings occupants?
Fire Exits
The Regulatory Reform (Fire Safety) Order (RRFSO) 2005, which came into
force in October 2006, charges the responsible person(s) in control of nondomestic
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” (14: 1) and that these “emergency
routes and exits must lead as directly as possible to a place of safety” (14: 2:
a)
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:
• A storey exit into a protected stairway or the lobby of a lobby approach
stairway;
• A door in a compartment wall or separating wall leading to an
alternative exit;
• 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. (NB: 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. Plus, the final exits on these escape routes (i.e. fire
exits) 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’re responsible for fire safety in business or other non-domestic
premises if you’re:
• an employer
• the owner
• the landlord
• an occupier
• anyone else with control of the premises, for example a facilities
manager, building manager, managing agent or risk assessor
You’re known as the ‘responsible person’. If there’s 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.
Fire safety rules are different in Scotland and Northern Ireland.
Responsibilities
As the responsible person you must:
• carry out a fire risk assessment of the premises and review it regularly
• tell staff or their representatives about the risks you’ve identified
• put in place, and maintain, appropriate fire safety measures
• plan for an emergency
• provide staff information, fire safety instruction and training
Non-domestic premises are:
- all workplaces and commercial premises
- all premises the public have access to
- the common areas of multi-occupied residential buildings
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 Suppresion Systems (common is server rooms / data centres)
Explain the different types of fire alarm system available.
Heat detectors
Smoke detectors
Wired
Battery operated
Type P - property protection
Type L - life protection
Type M - manual only
What would you use a type L fire alarm system for?
Life protection
Automatic fire detection in key areas
