What altitude are planes pressurized to for diving safety?

Aircraft are generally pressurized to an altitude of around 8,000 feet for both passenger comfort and safety. This altitude is a compromise that allows for a safer environment for individuals, including those who may have recently been diving. At this pressure level, the partial pressure of nitrogen is still within safe limits for divers, minimizing the risk of decompression sickness, often referred to as "the bends."

Pressurizing to this altitude ensures that divers can safely ascend to the surface of the water without significant risk factors associated with higher altitudes, such as increased nitrogen elimination from the body. Decompression sickness is primarily a concern for divers because as they ascend, nitrogen that was absorbed in the body compresses and can form bubbles if the ascent is too rapid or if the diver goes to altitude too soon after diving. Therefore, maintaining the cabin altitude around 8,000 feet helps protect the health of divers who are traveling by air shortly after their underwater experiences.