Which statement about the rate of decompression is true?

Which statement about the rate of decompression is true?

• A. Decompression only occurs slowly
• B. Decompression can be rapid or explosive, depending on leak size
• C. Decompression only occurs in the engine
• D. Decompression never affects oxygen levels

Answer: (B)

Rate of decompression is determined by the size of the breach in the pressurized cabin. A large breach lets air rush out very quickly, causing explosive or rapid decompression with a swift drop in cabin pressure. A small leak allows air to escape more slowly, so the pressure decreases gradually over a longer time. This is why the statement saying decompression can be rapid or explosive, depending on leak size, is the best fit. Oxygen levels are tied to cabin pressure, so any drop in pressure means a reduction in the available oxygen partial pressure inside the cabin—hence emergency oxygen systems may deploy in rapid decompressions and still be relevant in slower ones. The idea that decompression only happens in the engine isn’t accurate, since a breach anywhere in the pressurized structure can cause decompression, and saying it never affects oxygen levels contradicts how pressure and gas mixtures work in a pressurized cabin.

Rate of decompression is determined by the size of the breach in the pressurized cabin. A large breach lets air rush out very quickly, causing explosive or rapid decompression with a swift drop in cabin pressure. A small leak allows air to escape more slowly, so the pressure decreases gradually over a longer time. This is why the statement saying decompression can be rapid or explosive, depending on leak size, is the best fit.

Oxygen levels are tied to cabin pressure, so any drop in pressure means a reduction in the available oxygen partial pressure inside the cabin—hence emergency oxygen systems may deploy in rapid decompressions and still be relevant in slower ones. The idea that decompression only happens in the engine isn’t accurate, since a breach anywhere in the pressurized structure can cause decompression, and saying it never affects oxygen levels contradicts how pressure and gas mixtures work in a pressurized cabin.