What is the primary difference between ear squeeze and reverse ear block?

The primary difference between ear squeeze and reverse ear block lies in the relationship between the pressure inside the ear and the external pressure. Ear squeeze occurs when the pressure inside the middle ear is lower than the external pressure, typically during descent underwater. This pressure difference can pull the eardrum inward, leading to discomfort, pain, and potential injury if not equalized.

In contrast, reverse ear block happens during ascent when the pressure in the middle ear is greater than the pressure outside, which can create a backlog effect, causing the eardrum to bulge outward. This situation can create discomfort as well, but the mechanisms and circumstances surrounding these two conditions differ significantly. Understanding this distinction enables divers to recognize when and why they might experience ear issues while diving, allowing them to take appropriate actions (like equalizing) to prevent or address ear-related problems effectively.