SIDESHIELDS - LIMITED PERIPHERY COMPLAINTS
 

This is a very common complaint from people who are faced with having to wear side protection for the 
first time.  The basis of the complaint is really not valid because the amount of visual acuity in the 
periphery is minimal even without side protection.

This issue has been raised several times during the technical committee meetings at CSA. After much 
discussion it was agreed that a notation be included in the standard which would, at the very least, note 
that such a problem exists.

In section 6 of the standard it reads:
6.2.1	Side Protection
Protective spectacles shall incorporate side protection (See Clause 6.3.2).
Note:  Some forms of side protection may not offer adequate optical quality for clear 
peripheral vision.

Unfortunately, sideshields are made out of one of two different materials, acetate (plastic) or 
polycarbonate.  Neither of these two materials allows much visual acuity or clarity.

The main complaints seem to come from lift truck operators who contend that they need peripheral vision 
to avoid accidents.  

The most effective counter measures to the complaint are:
1.	USES:  Fork lift operators should always turn and look where they are going.  Relying on 
peripheral vision is not a very safe method of determining where objects are in the periphery.
2.	ADAPTION:  People wearing protective eyewear have the same complaint about the rims of 
the eyewire.  The complaint is that they "see" the eyewire and it is distracting.  The fact of the 
matter is that once a person is wearing eyewear they naturally adapt to looking through the 
optical center of the lens in a circle about the size of a 10 cent piece.  After a very brief period 
of time the eyewire becomes "invisible".
3.	ADAPTION:  "Try it for a longer period of time".  As in any personal protective device there is 
a certain amount of getting use to having something foreign placed in front of your eyes.  The 
resistance to change issue which is more the problem than anything else will diminish and 
often disappear after a brief period of time.
4.	FIT:  Make sure that the eyewear is not too tight to the side of the face.  Eyewear that is too 
narrow will bring the sideshields closer to the eyes and therefore make them easier to see in 
the periphery.  A slightly wider frame will decrease the apparent existence of the sideshield.  
Also make sure that the eyewear does not sit too far forward on the wearers face.  The 
proximity of the lens to the eye (vertex distance) should be about 15 to 20 mm.  If the 
eyewear sits too far forward the sideshields will appear very prominent in the person's vision.
5.	EDUCATION:  Education of the wearer.  Sideshields were introduced as mandatory in 1992 
because of overwhelming evidence of eye injuries caused by side impacts.  The sideshield is 
purposely designed to protect the eye from hazards that would otherwise cause injury.  
6.	AUTO REFLEX:  People who wear regular prescription eyewear are less likely to have 
problems because they have become accustomed to turning their head to see clearly.  Not 
just in the periphery but for normal daily visual acuity at all ranges.  The human auto reflex 
system will train your eyes to focus at the point where acuity is greatest.  It becomes the 
same as breathing.  And, the higher the prescription the more focused a person becomes.