# Cabin Pressure Reduced cabin pressure causes a *reduction in sound transmission*. Sound needs a medium to pass through.This means that crew members have to **talk louder to be heard **. The problem becomes more noticeable as the distance between individuals increases. The sound reflected from room surfaces is known as reverberation. If the delay relative to the original sound is small, the reflections and the original will fuse and be heard singly by the listener. If the delay is long, a separate sound (an echo) will be heard Vestibular side effects: 1. Spatial disorientation 2. Space adaptation syndrome (space sickness) > Need for tech / solutions that help balance body pressures #Kareena