KM-37 UBA Flashcards
the KM-37 face port is made of __________
1/4” Lexan
what does the dial-a-breath do?
- controls breathing resistance
- increases or decreases spring tension
- offers diver control over regulator sensitivity and ability to compensate for varying OBPs settings
what is the purpose of the gas supply nonreturn valve?
prevents a reverse flow of gas from the helmet to the umbilical
what feature prevents both barotrauma and loss of emergency breathing gas if depressurization of the umbilical occurs?
gas supply nonreturn valve
what is the LP port used for?
dry suit inflation
what does the bent tube assembly port do?
channels breathing gas from the gas supply nonreturn port and the EGS valve port to the demand regulator
what does the steady flow valve port do?
channels breathing gas to the gas train inside the helmet
what are the 4 purposes of the steady flow valve assembly and gas train?
- defogging
- secondary breathing source if demand regulator fails
- de-water the helmet
- ventilation
how is the exhaust / water dump valve assembly activated?
by increasing pressure in the hat by using the steady flow valve
the EGS is mandatory for dives deeper than ______ fsw or when ________________
- 60 fsw
- diving in enclosed / confined spaces
the KM-37 first stage regulator is set at manufacturer’s recommended pressure but no lower than ______
135 psig OBP
the pressure relief valve on the first stage is set at ____ +/- ___
180 +/- 5 psig
the umbilical assembly is not to exceed _____ ft in length
600
a KM-37 dive mission will be considered complete if a break of ___ days or more in service is anticipated
7
an EXTENDED KM-37 dive mission is one that exceeds ___ days without any one break in service of ___ days or more
- 30
- 7
during extended KM-37 dive missions, mission maintenance must be performed every ___ days
30
mission maintenance is required PRIOR to a mission if only one of which criteria are met?
- equipment has never been used
- equipment has been idle for > 24 months
- condition is suspect
mission maintenance is NOT required prior to a mission if one of which criteria apply?
- helmet idle for 24 months or less and has tag certifying sat completion of full maintenance procedure within the last 24 months
- maintenance requirement card has been performed since last use of equipment
KM-37 normal working limit on AIR:
190 fsw
KM-37 maximum working limit on AIR:
285 fsw
KM-37 normal working limit on HeO2:
300 fsw
KM-37 maximum working limit on HeO2:
380 fsw
air supply system must be able to provide an average sustained flow of ____ acfm to the diver
1.4
air consumption varies between ___ and ___ acfm in the demand mode
0.75 and 1.5
in the free flow mode, greater than ___ acfm is consumed
8
what is the desired KM-37 OBP for 0-60 fsw? what is the range?
135 psig (90-165)
what is the desired KM-37 OBP for 61-130 fsw? what is the range?
135 psig (135-165)
what is the desired KM-37 OBP for 131-190 fsw? what is the range?
165 psig (165-165)
what is the formula for variable rate (required cylinder pressure)?
Vr = (D+33)/33 x 1.4 x time
how do you convert total scf to psi required?
psig required = Vr/FV x 14.7 + Pm
FV = floodable volume Pm = minimum cylinder pressure
the dry suit is composed of _____________
closed cell rubber lining with nylon
