Author Topic: Meeting required Visual Standards.  (Read 4206 times)

Offline OtisBrown

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Meeting required Visual Standards.
« on: March 19, 2012, 03:57:22 PM »
Subject: Here are the CA standards. 

I always advocate that a person working on prevention, obtain a Snellen (visual acuity) chart, set it up with a bright light on it -- and read it.

I always advocate that you understand the line you explicitly must pass.  Here are the California requirements -- but the closely match the other states.  Obviously, in time, by using the plus, you would want to slowly clear the 20/25 to 20/20 line.  For comparison, the FAA 3rd class license, requires that you have 20/40 (or better) in each eye.  I you are seeing 20/50, you should consider the "target" as exceeding the 20/40 line.  Always be safe, and always be legal. For personal self confidence I advocate you get two $9 test lenses (-1/2 and -1) to confirm your refractive state yourself -- so you know your eye is capable of 20/20 vision -- before you start wearing a plus to change your refractive state from -3/4 diopters to 0.0 diopters (necessary to  pass the 20/20 line.

DMV's Vision Screening Standards

DMV is authorized to test all applicants’ vision under California

Vehicle Code (CVC §12804.9(a)(1)(E) ).
Anyone who applies for an original or renewal driver license must meet
the department’s visual acuity (vision) screening standard. DMV’s
vision screening standard is:

20/40 with both eyes tested together and

20/40 in one eye and

20/70, at least, in the other eye

Minimum Visual Acuity Requirement

If you cannot meet the vision screening standard, you must have a  minimum visual acuity in at least one eye better than 20/200 (best  corrected). Visual acuity is a person’s ability to see items clearly  and sharply and to recognize small details. You may wear glasses or  contact lenses to meet the minimum visual acuity standard but you  cannot wear a bioptic telescopic or similar lens. DMV can not license  drivers who do not meet the minimum visual acuity standard.

Offline OtisBrown

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Re: Meeting required Visual Standards.
« Reply #1 on: March 19, 2012, 04:08:06 PM »

Subject: On the Snellen -- how many letters must I read to pass that line?

Statement by Mike Tyner Optometrist

Tyner>  Strictly, "20/40" by itself only means you got more than half right.

20/40+1 means you got all the 20/40 letters right, plus one off the next
line (20/30).

20/40+1/-1 means you got one 20/40 wrong but you guessed one of the 20/30
letters right.

20/40-0 emphasizes that none were missed.

20/40+0 means that 20/30 was attempted.


I have the letters marked with a felt-tipped pen, so I can read them at 20 feet.  I recommend that anyone working with his own Snellen do that.

The more typical scenario is that you read all the letters on the 20/50 line, perhaps 1/2 the letters on the 20/40 line, and maybe one letter on the 20/30 line.

This is how you make your own objective measure of your visual acuity.  Using a -1/2 would clear the 20/25 line (for example) and a -1 would clear the 20/20 line (or better).

The point of doing that is to have you personally and objectively measure your refractive state yourself.  This process is highly recommended, but please accept that it can take from seven months to a year to "clear off" that negative status for your natural eyes.

Offline OtisBrown

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Re: Meeting required Visual Standards.
« Reply #2 on: January 28, 2013, 10:20:45 AM »

Subject: Update on REQUIRED Visual Acuity  - for your State.

If you are working on "Vision Improvement", you need to know the REQUIRED standard.  Here it is - State by State:

Note:  A large number require 20/40 or better, with one eye at 20/70, the other at 20/40.  (This is NORMAL variation).  This is why I would insist that you have your OWN Snellen - to do your own checking.  I would always plan to EXCEED this requirement, as is only reasonable, even if it takes more work with the plus to change my refractive STATE by +3/4 diopters. 

If you fly an airplane, the FAA (3rd) requirement is 20/40 in both eyes.  The FAA 1st, is 20/20 in both eyes.  Here is that requirement.

If you are a pilot - then it is even MORE important to monitor your own Snellen.  If the FAA rejects you - it is essential that you get yourself BACK to 20/20.

For the record, here are the MILITARY requirements.  But again, they require 20/20 - both eyes.

Very few of us wish to be military pilots.  I maintain that I must ALWAYS pass the 20/40 line - personally.  I expect it of myself.

I see that requirement as a "warning" to me, if, for long-term close work, I find my refractive STATE "moving negative".  It is up to *ME* to "fix it"  - because NO OD WILL HELP ME DO IT.

Be wise - protect yourself.