Application of Detectors
When designing a fire protection system, it is important to
understand and identify the characteristics and fuel material of a
potential fire, the environment in which the detector will be sited
and the risk of fire.
Relative performance of Apollo point detectors in test fire:
Smoke Detectors
Smoke detectors are recommended for general use as they give the
highest level of protection. They must be used in escape routes to
provide sufficient early warning to allow the evacuation of
occupants. There are two types of smoke detectors that are
recognised as good general purpose detectors and they are available
in both conventional
and analogue
addressable:
Ionisation smoke detectors
- High sensitivity to fast burning, flaming fires that produce
small smoke particles
- Widely used for applications such as priniting workshops, paper
mills and paint stores
- Good for general purpose
Optical smoke detectors
- Suited to detecting slow burning, smouldering fires which
produce large smoke particles
- Used in areas such as bedrooms, escape corridors, and
electrical switch rooms
- Also good for general purpose
Heat Detectors
Apollo offers both conventional
and analogue adressable heat
detectors. These detectors offer protection in environments
that are dirty or smoky in normal conditions such as kitchens or
garages. They are also effective in areas that contain high levels
of airborne particles such as water vapour and exhaust fumes.
It is important to note that heat detectors will respond
only when a fire is well-established and generating a high heat
output.
Rate-of-rise detectors
- Designed to sense rapid increase in temperature
- Effective in environments where the ambient temperature is
normal
Fixed temperature heat detectors
- Signals alarm when temperature surpasses a pre-defined
level
- Effective in areas with fluctuating temperatures, such as
boiler rooms
- Good for environments with a particularly high temperature
Multisensor Detectors
Multisensor detectors combine features of optical and heat
detectors. This means they provide good general detection that
responds to both smouldering fires (optical) and fast-burning fires
(heat).
Combined sensors enhance the detection performance
Improve resistance to factors that may produce false alarms
Suited for environments such as hotel bedrooms and warehouse
loading bays
Apollo has both conventional
and analogue adressable multisensor
detectors.
CO Detectors
CO Detectors do not detect heat or smoke. Instead, they sense
levels of carbon monoxide (CO) given off in the early smouldering
stages of a fire. This means they are able to provide an early
warning of fire in certain well-defined circumstances.
Note: CO detectors should not be used as a replacement for
smoke or heat detectors but they do provide excellent support to
fire detection systems.
Visit the Discovery CO detector page for
more information.
Optical Beam Detectors
The optical beam detectors use an infra-red light
sent from a transmitter to a receiver. Alarm state is reached when
smoke obscures the beam of light. This means they are ideal for
protecting large, open spaces such as church halls and
warehouses.
Flame Detectors
Flame detectors are designed to detect
either ultraviolet (UV) or infra-red (IR)
radiation emitted by fire. They can even detect gas fires which are
invisible to the naked eye.
Effective in protecting areas where open flaming fires may be
expected
Unaffected by air currents, and tolerant of fumes, vapours and
dust
Applications include oil refineries, power plants, paper works
and car factories
Intrinsically Safe
Intrinsically safe detectors are versions of
optical and heat detectors specifically designed to protect areas
where explosive mixtures of gas and vapour may be present.
Designed so they cannot ignite the explosive area in normal or
fault conditions
Used in chemical engineering plants and factories holding gases,
solvents and paints
Apollo offers XP95 or Orbis versions of intrinsically safe
detectors
Marine Detectors
Marine detectors
operate in the same way as standard devices but are subject to
additional approval tests specific to the marine environment.
Apollo offers Orbis and Discovery versions of detectors that are for
suitable use in the marine environement.