CHT Hyperbaric Physics and Gas Laws Flashcards
7 cards from real Certified Hyperbaric Technologist Test practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 CHT Hyperbaric Physics and Gas Laws flashcards as text
A sealed flexible bag holds 6 L of gas at the surface (1 ATA). At 3 ATA in a hyperbaric chamber, what is its approximate volume, assuming constant temperature?
Answer: 2 L
Boyle's Law gives V2 = (P1V1)/P2 = (1 x 6)/3 = 2 L.
Which gas law best explains why nitrogen narcosis worsens as a diver or chamber occupant goes deeper?
Answer: Henry's Law
Henry's Law states the amount of gas dissolved in tissue rises with partial pressure, increasing nitrogen's narcotic effect.
At 2 ATA, what is the partial pressure of oxygen in air (21% O2)?
Answer: 0.42 ATA
Partial pressure = fraction x total pressure = 0.21 x 2 = 0.42 ATA.
Dalton's Law of partial pressures states that the total pressure of a gas mixture equals what?
Answer: The sum of the partial pressures of each gas
Dalton's Law: total pressure is the sum of each gas's partial pressure.
Why does a sealed rigid gas cylinder show increased pressure when moved from a cold storage room into a warm chamber?
Answer: Gay-Lussac's Law
Gay-Lussac's Law states pressure is directly proportional to absolute temperature at constant volume.
Approximately how much does ambient pressure increase for every 33 feet of seawater depth?
Answer: 1 ATA
Each 33 fsw adds approximately 1 ATA to ambient pressure.
A patient breathing 100% oxygen at 2.4 ATA receives an inspired oxygen partial pressure of approximately what?
Answer: 2.4 ATA
With FiO2 of 1.0, PO2 = 1.0 x 2.4 = 2.4 ATA.
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