Pressurisation ductwork is a
passive fire protection
Passive fire protection (PFP) is components or systems of a building or structure that slows or impedes the spread of the effects of fire or smoke without system activation, and usually without movement. Examples of passive systems include floor- ...
system. It is used to supply fresh
air
An atmosphere () is a layer of gases that envelop an astronomical object, held in place by the gravity of the object. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A stellar atmosph ...
to any
area of refuge, designated
emergency evacuation
Emergency evacuation is an immediate egress or escape of people away from an area that contains an imminent threat, an ongoing threat or a hazard to lives or property.
Examples range from the small-scale evacuation of a building due to a storm ...
or egress route.
Purpose
The purpose of pressurisation ductwork is to maintain
positive pressure
Positive pressure is a pressure within a system that is greater than the environment that surrounds that system. Consequently, if there is any leak from the positively pressured system, it will egress into the surrounding environment. This is in ...
in building spaces to prevent smoke from entering from other spaces in which a fire is occurring. It is typically used in exit stairways, corridors, and lobbies.
Requirements
Pressurisation ductwork is
certified
Certification is part of testing, inspection and certification and the provision by an independent body of written assurance (a certificate) that the product, service or system in question meets specific requirements. It is the formal attestatio ...
on the basis of
fire test
A fire test is a means of determining whether fire protection products meet minimum performance criteria as set out in a building code or other applicable legislation. Successful tests in laboratories holding national accreditation for testing and ...
ing such as
ISO 6944.
Systems
There are two means of providing fire-resistance rated ductwork:
*Inherently fire-resistant, or