Peripheral Complaints Resulting 
From Wearing Side Protectors
 

The following excerpt is from a study by the US Naval Weapons Center
China Lake, California¹, titled:

 "The Effects of Safety Glasses Sideshields on Peripheral Vision"

ABSTRACT
The degradation of peripheral vision through the sideshields of six different safety glasses 
was measured.  Peripheral resolution was found to be degraded less than 8 percent by the 
worst case sideshield tested.

Field of view was measured for each of the safety glasses.  Full field of view was found 
to range from approximately 79 degrees for a set of goggles, to approximately 138 
degrees for a set of plastic folding glasses.

OBJECTIVE
This report documents studies of two primary visual characteristics of the sideshields:  
(1) visual resolution through the sideshields, and (2) restricted visual field due to the 
limited field of view and to the amount of visual obstruction caused by the oversized 
frames that are needed to support the sideshields.

CONCLUSION
Peripheral visual resolution was determined for a set of six different sideshields taken 
from six different safety glasses.  Two of the sideshields (both for goggles) degraded 
foveal² vision significantly.  However, calculated peripheral resolution was only slightly 
affected for the worst case shield, degrading resolution by approximately 8 percent 
maximum, at 40 degrees into the periphery.  Most sideshields begin at 50 degrees or 
further into the periphery where the effect on acuity is even less.  No statistically reliable 
degradation was found for the other four sideshields.  Therefore, visual resolution is not 
importantly degraded in the peripheral area by any of the sideshields.  Moreover, turning 
just the eyes to look through the shield foveally is unlikely since maximum eye 
movement is normally 35 degrees to left or right whereas most shields do not begin to 
appear until approximately 50 degrees or further.

¹Donald W. Peterson
 Targeting Division
  Aircraft Weapons Integration Department
  Naval Weapons Center, China Lake, California
  January 1982

²Foveal vision is the most acute, direct vision used for reading and seeing detail.