SPECIAL PRECAUTIONS FOR FROZEN SECTION TECHNIQUE:

        Requests for frozen sections of tissue from patients known or suspected to be infected with HIV should be strongly discouraged. However, exceptional circumstances may lead to such use of the cryostat. The following recommendations are designed to allow safe handling of the specimen. Remember: handle all specimens as if they were infectious at all times.

1.    Always wear double gloves, eye glasses, mask and gown whenever suing the cryostat. Never        reach into the cryostat for any purpose without wearing gloves.

2.    Confine possible bench top contamination to small area.

3.    Do not create any aerosol within the cryostat. Never use aerosol freezing spray (such as Quik-
       Freez, Frostbite) to cool tissue.

4.    Briefly immerse the entire frozen section slide in 10% formalin. Then remove gloves and with draw        the slide with clean forceps and proceed with staining.

5.    When staining is completed, put on clean gloves and remove the specimen from the specimen        holder. Place it in fixative or wrap in a small piece of clean aluminum foil, place in a labeled plastic        bag and store frozen.

6.    On a regular basis and whenever special circumstances warrant it, decontaminate the cryostat as        follows:
  • Turn off refrigeration.
  • With protective clothing in place, remove the knife from microtome and place it in a pan of 95% ethanol for at least 15 minutes. If complete defrosting is desired, pour a small amount of 95% ethanol on the floor of the cryostat chamber where water will collect.
  • Wipe all exposed surfaces inside and outside the cryostat chamber with a towel or sponge that has been soaked in 95% ethanol. Allow the cryostat to dry completely to prevent moving parts from freezing together.
  • Lubricate according to the manufacturer's instructions.
  • Replace the knife or use a clean microtome knife from freezer.
  • Turn on refrigeration for return to desired temperature.
NOTE: Never use bleach (sodium hypochlorite) in the cryostat since it will corrode the metal components.