FMCSA Medical Examiner Handbook

The Snellen chart or the Titmus Vision Tester measures static central vision acuity. The requirement for central distant visual acuity is at least 20/40 in each eye and distant binocular visual acuity of at least 20/40. ... The additional testing may be requested by the medical examiner from the primary care physician, cardiologist, or ... ................
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