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Caring for Your Surgical Instrument Investment: Sterilization

Caring for Your Surgical Instrument Investment: Sterilization

In this video, you get some practical tips on sterilizing your surgical instruments and using an autoclave. This video is the fourth in a series of four to discuss some best practices in caring for your surgical instrument investment.


Autoclaving, which is saturated steam under high pressure, is the most common method for sterilizing surgical instruments, but a cold sterilization method may also be used.

Prior to sterilization, clean the instruments and lubricate all hinged instruments with a surgical instrument lubricant. *Do not use WD-40, oil or other industrial lubricants.*


Cold Sterilization


Cold sterilization involves soaking instruments in a cold sterilant like Cidex® for at least 10 hours. This process may be detrimental to fine instruments.

If disinfection is all that is required (and not sterilization) a 10­–90 minute soak in Cidex® may be all that is necessary.

When using instruments with tungsten carbide inserts, avoid using solutions with benzyl ammonium chloride



If you prefer to autoclave, instruments may be autoclaved individually or in sets.


  • Disposable paper or plastic pouches are ideal or autoclaving individual instruments. Use a pouch wide enough for instruments with ratchet locks, like needle holders and hemostats. The instrument needs to be sterilized in an open (unlocked) position.
  •  For sets, unlock all the instruments and sterilize them in an open position. Place heavy instruments on the bottom of the set when two layers are required.


Tips for Autoclaving:


  • Always autoclave instruments in an open position. Locking an instrument prevents steam from reaching and sterilizing all the surfaces. And, heat expansion during autoclaving can cause cracks in the hinges of locked instruments.
  • Do not overload the autoclave chamber, as this may also hinder steam penetration.
  • Place a towel on the bottom of the pan to absorb excess moisture during autoclaving.
  • Instruments can be placed in sterilization trays or wrapped in paper or muslin before autoclaving. This helps to prevent contamination of the instruments after sterilization.
  • Arrange the instruments, sterilization trays or packs in the autoclave without stacking them. The steam must circulate freely inside the autoclave.

Follow the manufacturer’s directions for adjusting the time, temperature and pressure of the autoclave cycle. As a general rule of thumb, process unwrapped instruments at 121°C for 20 minutes at 15 PSI above atmospheric pressure or at 134°C for 3–4 minutes at 30 PSI above atmospheric pressure.
Process wrapped instruments at 121°C for 30 minutes at 15 PSI above atmospheric pressure or at 134°C for 15 minutes at 30 PSI above atmospheric pressure.


At the end of the autoclave cycle when the pressure reaches zero, unlock autoclave door and open it a centimeter or so to allow the steam to escape.  If the autoclave door is opened fully before the drying cycle, cold room air will rush into the chamber, causing condensation on the instruments. This will result in water stains on instruments and also cause wet packs.


Run the drying cycle as recommended by the autoclave manufacturer until all the instruments are dry. It should take about 30 minutes.


Using sterile tongs, remove all the instruments, trays and packages. Allow them to cool to room temperature before storing. Unwrapped items must be used immediately or may be stored in covered, dry, sterile trays for up to a week. Store wrapped packages in a warm, dry, closed cabinet. Instruments remain sterile as long as the wrap is dry and intact.


With proper care and maintenance, your instruments will last for years to come. Understanding the difference between cleaning, disinfecting and sterilizing can safeguard your research and protect your investment in surgical instruments, equipment and laboratory animals. If you have any questions about the care of your surgical instruments, visit our website, or give us a call.

Our Clients Include:

University College London
Imperial College
University of Cambridge
University of Oxford

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