Ballistic Studies in Eye Protection

Abstract

Abstract : This work was undertaken to evaluate ballistically the resistance to penetration of optical lenses and rabbit eyes by lead and steel BB's. Plastic CR39 lenses were tested, in addition to several types of glass lenses. On the basis of the evaluations, it was concluded that: the plastic lenses were the most resistant to both missiles. The 9-diopter lenses were, in general, superior to the 12-diopter ones, and the lead BB deformed against all lenses to varying degrees, while the steel BB deformed very little. For tests with eyes, the ballistic limit for the steel BB was higher than that for the lead BB, which is the reverse order to that for lenses. Neither the lead nor the steel BB deformed upon striking the eye. The unshielded eye, in some cases, may provide itself better protection against impacts by missiles below its ballistic limit than can be obtained from some lenses. Missile impacts below the ballistic limit of the eye, however, could cause injuries ranging from minor corneal contusions to internal structural damage. Eye armor is a definite asset to the protection of eyes, and any optically suitable material possessing encouraging ballistic properties, such as plastic CR39, could be considered a valid candidate.