Questions and CORRECT Answers
What pressure will a scuba cylinder with a rated working pressure of 3000 psig (207 bar), be
exposed to during a hydrostatic test? - CORRECT ANSWER - 5000 psig (345 bar)
Which principle represents one basis for the hydrostatic testing of scuba cylinders? - CORRECT
ANSWER - Permanent expansion
If a visual cylinder inspection reveals corrosion inside a scuba cylinder, it may require cleaning
by a process called: - CORRECT ANSWER - Tumbling
Which of the following is considered proper care of a scuba cylinder? - CORRECT
ANSWER - Preventing moisture from entering the cylinder.
Two cylinder valves in common use today are: - CORRECT ANSWER - The K-valve and
DIN valve.
Which valve is an example of a special scuba valve that is required for certain types of specialty
diving such as deep diving with a single cylinder? - CORRECT ANSWER - Y valve
Which internal valve designs are available in the first stage of scuba regulators? - CORRECT
ANSWER - Piston; Diaphragm
Which valve is unaffected by cylinder air pressure with regard to the force needed to operate the
valve? - CORRECT ANSWER - Balanced
Which regulator second stage design uses air pressure rather than mechanical leverage to open
the main valve? - CORRECT ANSWER - Pilot
, In the event of a regulator first stage malfunction, which type of valve design would be likely to
eliminate air flow to the diver? - CORRECT ANSWER - Upstream
When considering a regulator for purchase or use, an important point to remember is that certain
regulators may not be capable of delivering ______ flow rates at ______ cylinder pressure
during an air sharing emergency. - CORRECT ANSWER - high; low
Which diving instrument incorporates a Bourdon tube mechanism? - CORRECT
ANSWER - Cylinder pressure gauges
Two benefits derived from using an electronic dive computer are _____. - CORRECT
ANSWER - Accurate monitoring of ascent rate and, if executing a multi-level diving
profile, avoidance of the maximum time/depth penalty
Green discoloration on the first stage of a scuba regulator indicates _____. - CORRECT
ANSWER - Water has most likely entered the first stage
An air compressor used for filling scuba cylinders operates by the principle of _____. -
CORRECT ANSWER - Boyle's Law
Dry suits form a waterproof barrier, but require undergarments to be effective in cold water -
CORRECT ANSWER - True
In order to make an informed decision on equipment purchase, you need to have a solid
educational background concerning the _____ of diving equipment: - CORRECT
ANSWER - Types, Method of operation, Care and maintenance
The distance between successive wave crests is defined as _____. - CORRECT
ANSWER - Wavelength
The highest tides are called _____ tides, and the lowest tides are called _____ tides. - CORRECT
ANSWER - spring; neap