A diver's inability to equalize his/her ears during ascent could cause:

A diver's inability to equalize his/her ears during ascent could cause:

• A. a block or reverse block
• B. a ruptured eardrum
• C. lung collapse
• D. decompression sickness

Answer: (A)

Keeping middle ear pressure in line with the surrounding water pressure is essential whenever you change depth. On ascent, the outside pressure drops, so air in the middle ear would naturally expand and must be vented through the Eustachian tube. If you can’t equalize, the expanding air in the middle ear creates a pressure difference that makes the ears feel blocked. This situation is described as a block or reverse block, depending on the direction of the pressure difference. That immediate risk during ascent is the ear blockage. A ruptured eardrum can occur if the pressure difference becomes extreme, but the most direct consequence of failing to equalize during ascent is the ear block. Lung collapse and decompression sickness involve other mechanisms (lung overexpansion from holding breath; nitrogen bubbles forming with rapid ascent), not the blocked-ear scenario.

Keeping middle ear pressure in line with the surrounding water pressure is essential whenever you change depth. On ascent, the outside pressure drops, so air in the middle ear would naturally expand and must be vented through the Eustachian tube. If you can’t equalize, the expanding air in the middle ear creates a pressure difference that makes the ears feel blocked. This situation is described as a block or reverse block, depending on the direction of the pressure difference. That immediate risk during ascent is the ear blockage. A ruptured eardrum can occur if the pressure difference becomes extreme, but the most direct consequence of failing to equalize during ascent is the ear block. Lung collapse and decompression sickness involve other mechanisms (lung overexpansion from holding breath; nitrogen bubbles forming with rapid ascent), not the blocked-ear scenario.