The tutor talks about the definition of a bar.

Bar is a unit of pressure: 100kPa, to be exact. By comparison, an atmosphere is 101.3kPa. Therefore,

1bar = (100/101.3)*1atm = 0.987atm

One atmosphere is 14.7psi. Therefore,

1bar = 0.987(14.7)=14.5psi.

Source:

Serway, Raymond. Physics for Scientisits and Engineers WPM. Toronto: Saunders College Publishing, 1986.

Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.