Cards (11)

  • What does SCUBA stand for?
    Self-Contained Underwater Breathing Apparatus
  • Who popularized SCUBA in 1943?
    Jacques Cousteau
  • What type of SCUBA system is used in over 99% of diving?
    Open-circuit demand system
  • What are the main components of an open-circuit SCUBA system?
    1. Tanks of compressed air or breathing mixture
    2. First-stage reducing valve
    3. Inhalation demand valve and exhalation valve
    4. Mask and tube system with dead space
  • What is the function of the first-stage reducing valve in SCUBA?
    It reduces high pressure to low pressure
  • How does the demand valve work during inhalation?
    It opens with negative pressure to release air
  • What happens to the air during expiration in SCUBA?
    It is expelled into the water
  • Why is there a limitation on the time one can remain underwater with SCUBA?
    Due to the need for airflow to remove CO2
  • What is the effect of depth on airflow requirements in SCUBA diving?
    Greater depth requires more airflow per minute
  • How long can a diver typically remain at a 200-foot depth?
    Only a few minutes
  • What is the role of the mask in a SCUBA system?
    • Provides visibility underwater
    • Houses the inhalation and exhalation valves
    • Connects to the breathing tube