Eye Safety

Robert Cholewick                   Whitney Young A/C
                                   211 S. Laflin
                                   Chicago, Ill.  60607
                                   312-997-3739

Objective:

To make the students aware of the need for eye safety in the classroom through 
three mini labs. 

Materials:

(part 1) Three styrofoam plates with a face drawn on each, a spray bottle of 
acetone (nail polish remover), and a pair of glasses (use glass lenses).  

(part 2) An overhead transparency, permanent marker, and an eyedropper.  

(part 3) Obtain about 10 pig eyes from a friendly butcher shop, eight 25 ml. 
beakers with 5 ml. of sulfuric acid, magnifying glasses, eyedroppers, a dish for 
each eye, and a large amount of water. 

Strategies: 

(part 1) Treat each plate as a person cover one with plastic wrap and put the 
glasses on him.  Place him face up on a lunchroom tray and spray him with 
acetone.  The second plate put on the safety glasses and spray with acetone.  
The third plate just spray with acetone. 

(part 2) Draw a face with permanent marker on an overhead transparency.  Draw in 
each eye with a water soluble marker, for a dramatic effect paint the eyes with 
phenolphthalein and let dry.  Cover each eye with a contact lens disk cut from 
extra transparency.  For the actual class presentation place the face on the 
overhead with contacts in place add a few drops of water to the edge of the 
contact, use a mild sodium hydroxide solution for the face with the 
phenolphthalein.  

(part 3) After going over the results from the above aspects of eye safety place 
the fresh pig eyes in small dishes and have teams of students observe the pupil.  
Have one student carefully place 1-5 drops of sulfuric acid on the pupil, note 
the time in seconds, create a commotion resembling PAIN, rush the pupil to a 
water bath.  After washing examine the pupil for damage. 

Evaluation: 

     Have the students write a letter to a pen pal explaining what they have 
learned, be explicit.