FMCSA Contact: Sandra Zywokarte, MC-PSD, (202) 366-2987
For several years the Federal Motor Carrier Safety Administration (FMCSA), formerly the Office
of Motor Carriers of the Federal Highway Administration (FHWA), has examined whether to
revise its vision requirements for commercial motor vehicle (CMV) drivers. In 1997 the FHWA
convened a panel of medical experts to propose recommendations for amending the current
vision requirements (49 CFR 391.41(b)(10)) to more precisely evaluate the visual performance
necessary for safe CMV operation. This Tech Brief summarizes the final report issued by the
medical panel, Visual Requirements and Commercial Drivers.
FMCSA vision requirements must promote:
highway safety, by ensuring that only physically qualified drivers operate CMVs; and
the general goals expressed in the Rehabilitation Act of 1973 and the Americans with
Disabilities Act of 1990 that affect policymaking and persons with disabilities.
The current requirements are made up of widely accepted and easily administered vision tests,
which evaluate CMV drivers' central static "visual acuity," i.e., clearness of vision, and static
peripheral horizontal visual field. Under the requirements drivers must have: distant visual acuity of at least 20/40 (as measured by the standard Snellen chart test) in
each eye without corrective lenses, or visual acuity separately corrected to 20/40 or better
with corrective lenses;
distant binocular acuity of at least 20/40 in both eyes, with or without corrective lenses;
a field of vision of at least 70 degrees in the horizontal meridian in each eye; and
the ability to recognize the standard red, green, and amber colors in traffic signals and
Vision Requirement Waivers
To gather data for a possible change in the vision standards, in 1992 the FHWA created a vision
waiver program. After the U.S. Court of Appeals for the District of Columbia Circuit concluded
in Advocates for Highway and Auto Safety v. FHWA that the waiver program was contrary to
law, the FHWA ended the program in 1996. CMV drivers who already had received waivers
were allowed to continue to drive, subject to stringent requirements including an annual vision
In 1997 the FHWA convened a panel of four medical experts to develop recommendations for
improving the vision standard for CMV drivers. Any proposed changes to the requirements
would have to maintain a standard set of vision tests that could be administered using accessible
technology. The panelists held several meetings and discussed their proposed recommendations
with FHWA officials before submitting their final report in October 1998.
Findings & Recommendations
The report identifies two major problem areas in the vision testing requirements. First,
confrontation testing (i.e., abbreviated field assessment that tests vision of selected horizontal
points) could miss significant field defects, which have as muchif not moreimpact on visual
function when driving than visual acuity. Second, visualcognitive/motor skill variables are much
more relevant than static vision tests, but using a driving simulator to evaluate these skills is
currently impractical, except as part of a research study.
Field of Vision Requirement
The panel agreed with an earlier study that the field of vision standard of at least 70 degrees in the
horizontal meridian in each eye was intended to restate the binocular requirement in terms of
monocular testing, and the monocular field should have been 140 degrees (Decina et al., 1991). To
eliminate this ambiguity, the panel supported a revision of the field of vision standard to require at
least 120 degrees of horizontal field in each eye, instead of 70. The panel also recommended a new
requirement of at least 20 degrees of visual field both above and below the horizontal axis in each
The suggested field of vision requirements may be confirmed by a modified protocol using
confrontation visual field testing of each eye separately. CMV drivers who either fail to meet these
screening testing standards or have been identified as having a disease that could compromise the
visual fieldsuch as glaucoma, retinitis pigmentosa, stroke, or brain tumorshould be required to
have a full visual evaluation by an ophthalmologist or optometrist, including formal visual field
testing and a determination whether the drivers' vision satisfies the standard.
The panel suggested that the other three requirementsdistant visual acuity, distant binocular visual
acuity, and color visionbe left unchanged. Two further studies were recommended: one would
determine the extent to which visually impaired drivers, with careful evaluation and monitoring,
could safely operate CMVs; the other study would evaluate a computerized driving task simulator
as a potential mode to test CMV driving performance.
In 1998 the Transportation Equity Act for the 21st Century (Public Law 105-178) allowed the
FHWA to grant renewable 2-year exemptions from the vision standard if they are likely to
achieve an equivalent or greater level of safety than without such exemptions. The FMCSA
receives petitions for vision exemptions submitted by CMV drivers, evaluates their merits, and
then determines whether to grant the exemptions. The results are published in the Federal
The FMCSA plans to publish a Notice of Proposed Rulemaking this year seeking comments on a
proposal to amend the visual field requirement as recommended by the medical panel. The
proposed action would require a total horizontal visual field of 120 degrees in each eye and
would add a requirement for a total vertical visual field of 40 degrees20 above the horizontal
meridian and 20 below the horizontal meridian. After a public comment period the FMCSA will
consider all relevant information and decide whether to issue a final rule revising the vision
Berson, Frank G.; Kuperwaser, Mark C.; Aiello, Lloyd Paul; and James W. Rosenberg. Visual
Requirements and Commercial Drivers, Federal Highway Administration, Office of Motor Carriers,
NTIS No. PB2001-102803, Washington, D.C., Oct. 1998.
Decina, L.E.; Breton, M.E.; and L. Staplin. Visual Disorders and Commercial Drivers, Federal
Highway Administration, Office of Motor Carriers, FHWA No. FHWA-MC-92-003, NTIS No.
PB92-143015INZ, Washington, D.C., Nov. 1991.