Test.
The air in your cylinder was accidentally mixed with 0.5% carbon monoxide. If you took this to 20
meters/66 feet, what would the surface equivalent percentage be?
a. 0.5%
b. 1.0%
c. 1.5%
d. 5% - CORRECT ANSWER c. 1.5%
0.5% x ATA
0.5% x 3=
What is the gauge pressure at a depth of 34 meters/112 feet of freshwater?
a. 3.3 atm / 48.4 psi
b. 3.4 atm / 49.8 psi
c. 4.3 atm / 63.1 psi
d. 4.4 atm / 64.5 psi - CORRECT ANSWER a. 3.3 atm / 48.4 psi
34 x .97
Use 97% when calculating freshwater. It will get you close not exact
When viewed underwater, objects normally appear __________ due to __________.
a. Closer; refraction
, b. Farther way; visual reversal
c. Larger; turbidity
d. Smaller; conduction - CORRECT ANSWER a. Closer; refraction
In technical diving, decompression stops are planned so the diver doesn't end up with ___________ that
result in decompression sickness.
a. too low a partial pressure of nitrogen
b. an excessive gas pressure gradient
c. an emergency ascent
d. too high an oxygen gas tension - CORRECT ANSWER b. an excessive gas pressure gradient
If you take a full breath from your cylinder at 20 meters/66 feet, you're inhaling ________ the number
of air molecules as a full breath at the surface. Therefore, your gas supply will last _______ as long as
using the same cylinder at the surface.
a. twice; half
b. three times; three times
c. one third; one third
d. three times; one third - CORRECT ANSWER d. three times; one third
If a diver has consumed 100 bar/1400 psi after spending 10 minutes at 30 meters/99 feet, approximately
how much gas will he consume at 10 meters/33 feet if he spends 15, minutes there (assuming all other
factors remain the same)?
a. 37.5 bar / 525 psi
b. 75 bar / 1050 psi
c. 100 bar / 1400 psi
d. 300 bar / 4200 psi - CORRECT ANSWER b. 75 bar / 1050 psi