A scuba cylinder valve is opened by turning it clockwise.

• A. True
• B. False
• C. It depends on the valve
• D. Not enough information

Answer: (B)

Opening a scuba cylinder valve is done by turning counterclockwise (to the left) to allow gas to flow, and clockwise to close the valve. So, the statement that it is opened by turning clockwise is not correct. When you turn left, the valve stem retracts from its seat, letting air through; turning right seats the valve and stops flow. This standard direction keeps operation consistent and safe across typical scuba equipment. If you ever encounter a very unusual valve, always follow that specific device’s instructions, but for standard tanks, open by turning left.