For larger spills, it is important to wear a full face respirator.  The
Formalin fumes will reek havoc on the delicate tissue of the eye.  Also,
it is important to neutralize the formaldehyde.  There are a number of
commercially available Formalin spill kits, but for large spills where
it is sometimes financially disadvantageous to use the commercial stuff,
any good kitty litter with urea will neutralize the formaldehyde.

R. Don Luke 
South Georgia Medical Center
Department of Pathology
2501 N. Patterson St
Valdosta, GA 31602
(912) 259-4830