Definition - What does Ambient Pressure mean?
Ambient pressure is the pressure put on an object under atmospheric means such as a liquid or a gas. When an object comes in contact with this medium, a force is applied on it. Ambient pressure differs underwater and in the atmosphere. When in the atmosphere, the pressure drops with height above the ground. When underwater, ambient pressure is a combined force with the hydrostatic pressure as well. The pressure is measured in psi and there is a standard ambient pressure for everything in an environment that varies as per the depth and the medium.
Petropedia explains Ambient Pressure
Oil wellbores are drilled in order to get past rock formations and access the reservoir. However, the pressure underneath the earth’s surface is different from the one above ground. Ambient pressure is the pressure faced by an object when it comes in contact with the atmospheric medium. This pressure varies in different depths, temperatures and environments. Measured in PSI, ambient pressure is different in space, under seawater and inside the earth. It is important to consider this pressure before an oil well is drilled so that proper measures are taken before the drilling starts.