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  1. Wear appropriate protective clothing eg. laboratory coat, gloves and goggles.
  2. Weigh out 900g of sodium chloride and dissolve in warm water.
  3. Unscrew cap on porthole of formalin mixing tank (beneath cut-up bench). Place a funnel in the front porthole of the formalin mixing tank and pour sodium chloride solution into the main tank. Replace screw cap on porthole.
  4. Using the sealed pump attached to the formalin mixing tank , add 10 litres of formaldehyde to the main mixing tank.
  5. Turn on the mains water tap (adjacent to the tank) and fill the formalin mixing tank to the 100 litre mark, using the line on the tank wall.
  6. When mixed , using the sealed pump attached to the formalin mixing tank, pump 50 litres into the top tank where the solution is ready for use.
  7. 10% formal-saline solution can be dispensed from the tap with the red knob on the cut-up bench.

NB: See protocol on formaldehyde safety and COSHH form for formaldehyde for the hazards associated with this chemical.

100 litres of 10% Formal Calcium

  • 900g sodium chloride
  • 10L formaldehyde
  • 90L water

NOTE: No responsibility is assumed by The University of Nottingham or the Queens Medical Centre NHS Trust for any injury and/or damage to persons or property as a matter of products liability, negligence or otherwise, or from any use or operation of any methods, products, instructions or ideas contained in the material herein. It is the users responsibilty to ensure that all procedures are carried out according to appropriate Health and Safety requirements.

© Copyright 1997 University of Nottingham Medical School Division of Histopathology. This page was last built on Mon, May 5, 1997 with Frontier. Thanks for looking in. Comments to James.Lowe@nottingham.ac.uk