Converting Atmospheres to Pounds Per Square Inch or PSI

This example problem demonstrates how to convert the pressure unit atmospheres to pounds per square inch (psi).

Problem:

The pressure under the ocean increases roughly 0.1 atm per meter. At 1 km, the water pressure is 99.136 atmospheres. What is this pressure in pounds per square inch?

Solution:

1 atm = 14.696 psi

Set up the conversion so the desired unit will be cancelled out. In this case, we want psi to be the remaining unit.

pressure in psi = (pressure in atm) x (14.696 psi/1 atm)
pressure in psi = (99.136 x 14.696) psi
pressure in psi = 1456.9 psi

Answer:

The pressure at a depth of 1 km is 1456.9 psi.