Using a scleral contact lens-balloon combination, attached to a pressure transducer, lid pressure was determined on ten normal subjects. The average pressure developed during a blink was 10.3 mm Hg, whereas, an average of 51 mm Hg was developed during a hard lid squeeze.
Miller D. Pressure of the Lid on the Eye. Arch Ophthalmol. 1967;78(3):328-330. doi:10.1001/archopht.1967.00980030330011