Recommended Vision Standards for Police Officers (Revised 1985)

Transcription

1 Recommended Vision Standards for Police Officers (Revised 1985) James E. Sheedy, O.D., Ph.D. Jeffrey T. Keller, O.D., M.P.H. Donald Pitts, O.D., Ph.D. Gerald Lowther, O.D., Ph.D. Stephen C. Miller, O.D. ABSTRACT~A recommended vision standard for police officers is presented. The visual capabilities needed to perform various police duties are described. A specific vision standard, along with criteria for screening referral or screening failure are given each category of visual skills required for police work. KEY WORDS~A police vision, vision standards, occupational vision Preface Many occupations, because of the specialized visual tasks which are required or standards which job applicants must meet before they can be considered for the job. Establishing a minimum level of vision is a critical decision which must be based upon the requirements of the particular visual tasks of the occupation. Standards which are too stringent result in unnecessary elimination of qualified people whereas loose standards result in poor job performance and/or potential injury to the employee or the public. The establishment of vision standards for police officers is very critical because of the critical nature of the occupation and the potential injury that can occur with poor job performance. Many states and municipalities have been having difficulties in establishing and defending vision standards for police officers. The American Optometric Association Commission on Ophthalmic Standards has been concerned about this issue and has developed the following "Recommended Vision Standards for Police Officers" which have recently been approved for distribution by the AOA Board of Trustees. It is hoped that these recommendations will be of assistance to various states and municipalities and to optometrists who serve as consultants to police organizations and agencies in their communities. Further information regarding police vision standards can be obtained from the American Optometric Association, Commission on Ophthalmic Standards, 243 N. Lindbergh Blvd., St. Louis, MO Introduction Good vision is an undeniable requirement for the proper performance of the duties of a police officer. In order to assure an acceptable level of visual skills for its police officers, most municipalities have established minimum visual requirements for police officer applicants. There is currently a wide range of values used for vision standards across the country, and most municipalities have little justification for their standards and are unprepared to meet a challenge of their standards. The purpose of this document is to recommend the level of visual skills required by police officers based upon the best data and evidence currently available. The visual standards should be as job related as possible and must not be excessively stringent so as to needlessly prevent an applicant from being considered for employment as a police officer. There are several aspects of vision and visual skills which are necessary for a police officer. Each of these has a recommended standard which must be met by the police officer. A series of tests is typically administered to measure the visual abilities of the applicant who aspires to be a police officer candidate. Although a complete professional eye examination for each applicant is recommended whenever possible, a more cost-effective means of applying the standards is to have technicians screen the vision of the applicants.

2 For each area of vision, the standard which the applicant must meet is specified. For each standard there is also listed a "screening failure" and/or a "screening referral" criterion. The screening failure criterion means that the applicant may be disqualified on the basis of the screening results alone. Some of the areas of vision do not have a screening failure standard because professional evaluation is necessary to confidently establish whether the candidate meets the criterion. The screening referral criterion means that there is an aspect of the vision which needs to be evaluated by an optometrist or ophthalmologist. If an applicant does not meet the screening referral criterion, then her or she must be referred for a professional evaluation of whether or not the applicant meets that particular standard. Standards 1. Visual Acuity - Corrected (spectacles or contact lenses)! Standard~20/20 binocular (both eyes open)! Screening Referral~less than 20/20 binocular or 20/40 or worse with either eye alone must be referred for confirmation that candidate meets binocular vision standards (See Appendix A) 2. Visual Acuity~Uncorrected (no spectacles or contact lenses)! Standard~20/40 binocular (See Appendices B&C)! Screening failure-less than 20/40 binocular.! Screening referral-20/200 or worse with either eye alone must be referred for confirmation that candidate meets binocular vision standard (See Appendix B). 3. Hyperopia! Standard-less than 2.00D (spherical equivalent) of hyperopia in either eye.! Screening referral-binocular visual acuity (uncorrected) which does not decrease by at least one full acuity line with +1.50D lenses (See Appendix D) 4. Binocular Vision! Standard-clear, comfortable binocular vision with good stereopsis at all normal working distances and viewing angles with correction.! Screening referral-stereoacuity poorer than 80 on Titmus test or equivalent; or distance phoria equal to or exceeding 5 eso or 5xo; or near phoria equal to or exceeding 6 eso or 10 exo (See Appendix E). 5. Color Vision! Standard-normal or anomalous trichromacy (no filters may be used).! Screening referral-failure on a series of pseudoisochromatic plates (See Appendix F). 6. Visual Fields! Standard-normal visual field! Screening failure-failure to meet perimetry standards listed in Appendix G.! Screening referral-failure on a field screener (See Appendix G). 7. Pathology! Standard-no pathological conditions which impair or would eventually impair visual performance.! Screening referral-failure on ophthalmoscopic examination. Professional help and guidance should be utilized in the implementation of any screening or examination program. the specific means of implementing a program must be individually designed around the equipment, personnel, and cost restraints of the particular community.

3 Appendix A The police officer is required to perform many tasks which require critical vision. 1 The tasks of identifying license plate numbers while driving and identifying street signs in enough time to stop and/or turn a corner have been quantifiably analyzed 2 and compared to driving figures. 3 These tasks require 20/20 vision for proper performance. Ninety-eight percent of the population between the ages of 14 and 40 can be corrected to 20/20 vision in either eye. 4,5 In order to pass this criterion, the applicant may be corrected with either spectacles or contact lenses. Applicants who are unable to obtain 20/20 vision are referred for professional examination. Most will be able to pass this standard with proper spectacle or contact lens correction. If the applicant has 20/40 or worse vision best corrected in either eye, the quality of binocular vision and stereoacuity (depth perception) is questionable. 6,7,8 These individuals must be referred for professional evaluation of whether the binocular vision standard is met. Appendix B The applicant must be able to pass the uncorrected visual acuity standard without the aid of spectacles, contact lenses, or other refractive device. (See Appendix C) An uncorrected visual acuity standard is needed because officers perform many tasks which can result in having spectacles unwittingly removed in situations where the officer must still retain a level of vision to perform critical tasks. The tasks have been enumerated 1 and data presented 2 to show that such incidents occur. A critical task which an officer could be called upon to perform when deprived of this optical correction would be shooting a handgun at a criminal offender. Police shooting statistics 9 show that most firearm use occurs within twenty feet of the target and that sight alignment is not usually used. In this situation, target identification is the critical factor in determining whether to shoot or not. An analysis of this situation 2 shows that 20/40 vision is required to perform this task. Vision standards for driving in many states are also 20/40, and it could be reasoned that an officer may need to drive an automobile in an emergency situation after losing his optical correction. The uncorrected vision standard of 20/40 needs to be obtained only with both eyes open, not each eye individually. Appendix C A contact lens wearer is probably at less risk of having his or her vision correction dislodged or forcibly removed while on duty than is a spectacle wearer. Therefore, a police department may consider waiving the uncorrected visual acuity standard for a successful contact lens wearer under the following conditions: 1) The candidate must have been verified as a successful contact lens wearer for the year prior to application. 2) The department recognizes the need to routinely verify the need to routinely verify that the contact lenses are actually being worn while on duty. 3) The individual has at least annual examinations by an optometrist or ophthalmologist to verify that they are a continuing successful contact lens wearer. Appendix D Although the refractive error of the human eye tends not to vary between the ages of twenty and fifty, 10 the eye very predictably and without exception loses its ability to accommodate or change focus with age. The result of this is that younger individuals with hyperopia can see clearly at distance, but as they age, their distance vision will decrease. Published data show uncorrected hyperopia of diopters between the ages of 44 and 55 results in an acuity of 20/ Candidates with 2.00D or more of hyperopia will more than likely be unable to meet the uncorrected visual acuity standard when they reach this age range.

4 Appendix E Police Officers need to have clear, comfortable binocular vision. This is necessary so that they may have good depth perception and so that double vision is avoided. The stereo acuity (depth perception) requirements in the screening procedure are chosen so that most people with binocular vision will be able to meet them. 12, 13 The phoria referral criteria are taken from a vision screening study. 14 If an applicant does not meet any of the screening criteria, he/she should be referred for a professional evaluation of whether the applicant meets the binocular vision standard. Appendix F The color tasks which an officer must perform do not require fine color discrimination, but the officer must possess basic color naming skills. Applicants with milder forms of color vision deficiencies (anomalous trichromacy) still possess basic color-naming skills. Applicants with dichromacy or monochromacy do not possess the color naming skills required of a police officer. The pseudoisochromatic plates which are used to screen for color vision defects will identify nearly all color vision defectives, about 8% of the male population and 0.5% of the female population. These individuals need to be referred for a professional evaluation of whether they meet the standard which requires either normal or anomalous trichromacy. An anomaloscope is the best instrument for making this evaluation. There are not many of these instruments available. The American Optometric Association can assist local authorities in locating the nearest facility which possesses this instrument. In the absence of this instrument, a D-15 test can serve as the professional referee test. Appendix G A visual fields screening device, such as Harrington-Flocks 15 field screener should be used to test the visual fields of the applicants. Failures on a screening device should be referred for professional evaluation of whether the visual fields are normal as defined below. Normal visual fields, for referee purposes, are defined as follows: The extent of the peripheral visual field should be determined along the eight principle meridians for each eye with a perimeter arc. A large target (5mm. white at 33cm. or 20mm. white at 100cm.) should be used. The minimum acceptable values are: temporal 85º superior-temporal 51º superior 45º superior-nasal 48º nasal 54º inferior-nasal 48º inferior 64º inferior-temporal 80º Values less than this are acceptable only if they are completely compensated by the other eye in binocular viewing. Any central visual filed scotomas must also be completely compensated by the other eye in binocular viewing.

5 Appendix H Suggested letter to optometrist or ophthalmologist when professional consultations for a screening referral is needed: Date Re: We request that you determine whether the police officer applicant named above meets the following vision standards (as indicated): O.U. corrected acuity (distant) of 20/20 O.U. uncorrected acuity (distant) of 20/40 Less than 2.00D. (spherical equivalent) of hyperopia in either eye. Clear, comfortable binocular vision with good stereopsis at all normal working distances and viewing angles with correction. Normal color vision or anomalous trichromacy. No pathological conditions which impair or would eventually impair visual performance. Normal visual fields as defined on the attached sheet. STATEMENT OF EXAMINER: My findings confirm that the above named applicant Does Does Not meet the standards indicated above. Signed Optometrist/Ophthalmologist We appreciate your returning your signed statement to:

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