BA Flashcards
What are the advantagess of open air BA?
advantages:
-simple in operation
-quick to don
-are positive pressure
-cool, dry air
-less change of fatigue/stress/dehydration
-quick to recharge
What are the disadvantages of open air BA?
disadvantages:
-no pre determined duration
-large cylinder, short working time
What are 4 basic essentials for any ba operator?
self dicipline
training
confidence
team spirit
What order is the BA change of shift check?
1-General check
2-control module and batery check
3-pressure seal+ motion manual alarm
4-low air electronic alarm/voice projecter speaker test
Outline steps involved in a BA general check (step 1 of COS check)
-remove ba from appliance
-check that cylinder strap is secure
-ensure green hand wheel is closed finger tight
-check all components are clean and free of damage
-ensure shoulder and waist straps are fully extended
-check user details are correct on telly tag and tag is placed on board
-check demand valve and face mask are free of any debris/particulates
-check speech diaphragm for debris. give mask a shake if required
outline steps involves in control module/battery check (step 2 of COS ba check)
1-press and hold either green button for 5 secs
2-check battery status, change the battery if showing one bar
3- a green tick indicates battery has passed the self check test
4- if white cross in red circle appears, do a second check, if this fails, remove ba from use.
5- check operation of purge/park by ensuring demand valve is parked, open the cylinder valve and ensure cylinder is pressurized to a minimum of 250 bar.
outline steps involved in pressure seal/alarm check(step 3 of COS ba check)
-close cylinder valve fully (clockwise remember)
-allow control module to remain motionless for 10-25secs
-check for pre alarm sounds, red flashing buddy lights, pre alarm icon is displayed on control module and red triangle displayed on HUD
-shake to reset before it goes full alarm..
-keep alarm motionles for 30 secs to activate full alarm (3 diff alarm tones)
-check for red buddy lights and full alarm icon
-press left green button twice in 1 sec to deactivate(shaking wont stop it)
-now press and hold red alarm button on control module
-you should see all the indicators for full alarm
-deactivate by pressing right hand side green button twice in 1 sec on control module
-ensure in 60 secs pressure hasnt dropped by 10 bar
outline steps involved in low air electronic alarm/voice projecter speaker test (step 4 of COS ba checks)
-release air slowly by pressing the purge button on face mask/parking demand valave in time. try to get 99 bar or under in system pressure
-check for pressure drop alarm, red flashing buddy lights and blue triangle in hud
-buddy lights flash yellow , low pressure alarm sounds at 10 sec intervals
-hud displays yellow low pressure indicator
-press/hold blue voice projection button to turn off
-purge remaining air of system until red buddy lights are displayed, pressure in unit is below 55 bar. mechanical whistle sounds. once below 15 bar double tab green button to put into sleep mode
-park demand valve
What is the estimated working duration of a fully charged cylinder?
For a 6.8l cylinder charged at 300 bar, total L of air = 2040L (6.8x300)
Average L per minute consumed is 60 lpm.
2040/60 = 34 minutes. Working duration of 24 minutes, with 10 minutes as a safety buffer.
What is the quick, practical calculation for working duration in minutes?
actual working duration = (aircontents in cylinder (bar)/ 10 ) - 10 (exit /decon time)
example= 250bar/10 = 25 - 10
=15 min working time
how does open and closed circuit ba work?
Open circuit= utilizes positive pressure to expel contaminated air if theres a leak from poor fit. Air is exhaled into the atmosphere via a one way valve
closed circuit- exhaled air is re-circulated into equipment
name the components of BA equipment
What is the pressure range for each buddy light colour?
green= 300 - 100
yellow= 99-60
red-59-0
hud pressure status lights:
4 green = 300-271 hbar
3 green-= 270-181 hbar
2 green= 180- 100
1 yellow= 99-60
1 red= 59-0
what is the minumum pressure required to initiate buddy breathing?
150 bar