BA Set Overview Flashcards
What are the features of the BA?
Two stage
Self contained
Open circuit
Positive pressure
Compressed air
What BAR is the BA cylinder charged to?
300BAR
What is the volume of the BA cylinder?
2430 Litres
What is the weight of a BA cylinder?
4.8kg (fully charged)
What is the cylinder made of?
Composite
What markings are found on a cylinder?
Black and white quartered neck
How does the cylinder prevent inadvertent closing?
Ratcheted locking mechanism - valve
What are the features of a backplate and harness?
Rescue handle
Adjustable waist belt and shoulder straps
Swivel mechanism for the waist belt
Pinch clip for height adjustment
Webbing cylinder with clamp mechanism
What is the function of the BA Computer?
Monitor:
Cylinder contents
Wearer’s movement (via DDU)
Audible and visual alarms
Adequate Flow rate
Pneumatic leakage
Electronics
Minimum 2 hours battery remaining
What is the path of air through a BA set?
High pressure air enters the regulator and has 2 paths it can take:
Through the 25L per minute restrictor and up the pressure gauge within the DDU
Through a central bore and into the main body of the regulator.
What are the features of the Spiroguide pressure regulator?
Simple design
Self regulating spring and piston device that requires no adjustment
What pressure is air reduced to via the main regulator?
7 BAR (medium pressure)
What does the relief valve do and what pressure does it operate at?
13.5 BAR
Protects the medium pressure system from over-pressurisation.
What do the Spiroguide high pressure hose do?
Carries air from the manifold to the Digital Display unit (DDU) and audible warning device.
What do the Spiroguide medium pressure hose do?
Carries reduced pressure air from the regulator to the facemask and breathing valve
What does the supplementary supply hose connection do and where is it situated?
Right hand side of shoulder pad
Facilitate ease of connection/disconnection
Place to supplement air in an emergency
Where do you find cylinder pressure information?
DDU
Bourdon tube contents gauge
When will the whistle operate?
60 BAR +/- 5 BAR
What are the features of the breathing valve?
Plug in connection to facemask
Two channel system - different valves for inhalation and exhalation
Demand valve - air supplied only during inhalation
Purge facility
How long is your personal line?
1.25m to knot
6m full length
