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Fire Protection System
is a set of mechanisms (active or passive) that the buildings have to
protect themselves against fire risks. It’s main objective is to protect
human life, followed by reducing economic losses and allowing prompt
activity re start after fire.
Passive mechanisms are concentrated in project design and construction,
delaying and containing fire action to specific areas. In order to get
an efficient human evacuation, different normative establish aisle,
stairs and exit required measurements, maximum distances to safe areas,
architecture considerations (e.g. doors), exit ways protection (aisle
and stairs) so they have floors, roofs and walls fire resistant. To
delay fire to expand within the building, it has to be divided on fire
sectors so during an emergency evacuation, persons may go from one
sector to the next one, increasing safety level.
Active mechanisms are referred to fire protection system installation
and are dived into: Detection, Alarm, Signaling and Suppression.
Detection is done through automatic detectors (smoke, flame or heat) or
manual devices (e.g. pulse-pull). Alarm is done through megaphone or
flashers and signaled with green indicators on the exit ways.
Suppression is done through extinguishing agents (water, chemicals, foam,
etc.), contained on extinguishing devices connected by piping through
application devices (hose stations, sprinklers, deluges, etc.) which may
function manually or automatically.
Within the active considerations automatic sprinkler system are the most
effective ones; the sprinklers detect fire and are activated with the
temperature increase, releasing water exclusively where the fire is
detected and activating an alarm, with the water flow, in parallel. The
system fights the fire from the very beginning, avoiding it’s spreading
and generally suppressing it, while on the other hand it also cools down
architecture structures and contents, reducing potential destruction and
economical damage.
Another common active mechanism, not as definitive as the automatic
sprinklers due to it’s manual human activation, are the hose station
systems, which are integrated by a pipe network connected to a pump
system which supplies water. This network is connected to internal and
external cabinets, which have control valves, hoses, etc., that are used
manually to fight fire.
Alarm and detection systems are an addition to automatic sprinkler
systems, enhancing them, but can also be installed stand alone. It’s
objective is to give an alert at the very beginning of a fire incident
to proceed to suppression with manual mechanisms and evacuate according
to a defined procedure, which is pre programmed in systems like this.
Additionally there are some special hazards that require the use of more
specialized systems and extinguishing agents different than water, as
gas, foam and pulverized water, for structures with particular
conditions different from the common ones, such as a suppression system
based on foam for a warehouse of combustible or the protection of a site
based on a gas system.
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