equivalent oxygen pressure
oxygen pressure, equivalent (EOP)
A percentage value of the assumed oxygen pressure existing behind a contact lens. The oxygen pressure in the air corresponds to about 20.9% (or about 159 mmHg; that value is actually close to 155 mmHg because of the presence of water vapour) and each percentage point is equal to a pressure of about 7.4 mmHg.
Millodot: Dictionary of Optometry and Visual Science, 7th edition. © 2009 Butterworth-Heinemann