The U.S. Air Force and U.S. Navy recently adopted the MCU-2/P Chemical-Biological Mask to replace the M17 series of protective masks. Visual field plots were generated on a patient wearing each of these respirators. Although both resulted in a decrease of the visual fields, the magnitude of restrictions was far less with the MCU-2/P Chemical-Biological Mask.
The restrictions on the central and peripheral visual fields, resultant from wearing a M17 series mask, were measured on a subject with normal field of vision. The results showed a decrease in visual field in all meridians, with the nasal area being the most dramatically restricted.