Operators Manuals - ST XX28 - Issue 3



Warning - All external body and lid surfaces are hot during and immediately after sterilisation. Lift or move the autoclave by the top handle only.



Important - For correct operation of this autoclave it is essential that the chamber be filled with water up to the height of the studs before every use.



Foreword

Before using this Dixons Portable Autoclave please read this booklet carefully. Please ensure that all persons likely to use this product are correctly trained in its use in accordance with these instructions.

Your Dixons Portable Autoclave, operated in accordance with the manufacturers instructions, will give years of trouble free service without the need for any major servicing.

Every Dixons Portable Autoclave has been manufactured to the highest quality standards by a company complying with BS EN ISO9000 and is fully tested and ready for immediate use.

Dixons Portable Autoclaves are suitable for sterilisation of:
  • Laboratory equipment (glass and metal)
  • Culture media
  • Pharmaceutical preparations in sealed containers
  • Surgical and Veterinary instruments
  • Dressings and drapes
For the sterilisation of dressings and drapes it is recommended that a Dressing Drum or Wire Mesh Basket be used. These are available as a part of the range of accessories.

All Dixons autoclaves are particularly suitable for destructive sterilisation, as the operator is not restricted to a set cycle time. This can be adjusted to suit the application.



1 - Installation Procedure

1.1 - On receiving the autoclave remove all the cardboard protective covers. Unscrew the Wing Nuts and swing down the Drop Bolts. Twist the lid anti-clockwise until the locking lugs disengage and remove the lid. Remove all other packaging materials from inside the autoclave.

1.2 - Ensure that the following parts are included:
  • Autoclave body and lid complete with all fittings as illustration
  • Inner liner
  • Pair of liner Carrying Handles
  • White silicone gasket in lid
  • Operators manual
  • Test certificate
  • Hexagon key for safety valve adjustment
  • Pack of TST indicator strips
  • Power lead with IEC connector
1.3 - Ensure that no damage has occurred to any of the fittings paying special attention to the Pressure Gauge and Thermometer.

1.4 - The autoclave is now ready for use.



2 - Operation

Please read these operating instructions before using the autoclave to avoid any chance of misuse.

The autoclave is factory set to run at 121ºC. This is the maximum setting, which is suitable for most purposes. A lower setting can be used if required.

Many materials can be autoclaved at 121ºC. These include most metals, glass, silicone rubber and many plastics. If in doubt, consult the manufacturer of the instrument or equipment concerned as the manufacturer of the autoclave does not accept liability for damage of this nature.

2.1 - Remove the Inner Liner. Fill the outer chamber of the autoclave with water up to the height of the studs.

2.2 - Articles to be sterilised should be placed into the Inner Liner, a Wire Mesh Basket or a Bottle Rack. To sterilise porous loads (i.e. dressings and drapes) it is recommended that a Dressing Drum be used. The container should not be packed tightly, especially when dressings are being sterilised. It is important that steam can circulate freely. Place the Inner Liner / Wire Mesh Basket / Bottle Rack / Dressing Drum inside the autoclave.

2.3 - Check that the Lid Gasket is correctly seated in its groove on the underside of the lid. Place the lid on the autoclave and rotate clockwise until it hits the stops and the slots for the Drop Bolts line up in the lid and body ring. The 6 Wing Nuts and Drop Bolts should now be lifted up and lightly tightened in opposite pairs. This should be done - one in each hand - until the slack is taken up. Now tighten up in opposite pairs. Normal finger tightness is adequate.

2.4 - Close the Draw-off Cock and open the Aircock approximately 6 turns.

2.5 - Plug the power lead into the autoclave. Plug the lead into the mains (the green light will show connection to the mains). Turn on the red Switch (the red light will show power on).

2.6 - When the water begins to boil, steam will start to emit from the Aircock. It will splutter at first. Close the Aircock once it has stopped spluttering and a clean jet of steam is visible. It is imperative that a clean jet of steam is visible before closing the Aircock as this ensures all the air in the autoclave is expelled. Air pockets in the autoclave will cause sterilisation to be incomplete. It is advisable to use some form of sterilisation test e.g. the TST indicator strips supplied.

2.7 - The temperature will now continue to rise until it reaches the preset level.

2.8 - It is at this time that the sterilisation period begins. Section 3 deals with sterilisation periods.

2.9 - When the sterilisation period is complete, turn off the red Switch. Depending on the materials being sterilised, see section 2.10 or 2.11.

2.10 - Bottles or other sealed vessels containing liquid - do not, under any circumstances, open the Draw-off Cock or the Aircock or release pressure from the autoclave in any manner. To release pressure from the autoclave at this point could cause the containers to explode. Allow the autoclave to cool until the Thermometer shows 80ºC or less.

2.11 - Dressings, instruments and apparatus - (providing the apparatus does not have sealed glass containers holding liquid). Place a suitable receptacle beneath the Draw-off Cock and open the Draw-off Cock to release water and steam under pressure from the autoclave. When steam ceases to emit, close the Draw-off Cock and allow the autoclave to cool until the Thermometer shows 80ºC or less. During the cooling period a partial vacuum will form inside the autoclave. This will help in drying the contents.

2.12 - When the autoclave is cooled, the Aircock should be opened approximately 6 turns. Check that the Pressure Gauge is reading zero. Unscrew the 6 Wing Nuts in opposite pairs - one in each hand - 2 full turns. This will allow the lid to rise to a safe position, where it is still held captive, but has clearance enough to release any residual pressure still in the Autoclave. Unscrew the 6 Wing Nuts fully in opposite pairs - one in each hand - and swing down the Drop Bolts. Twist the lid anti-clockwise until the Locking Lugs disengage. Remove the lid.

2.13 - Remove the sterilised contents.



3 - Sterilising Periods

The following times apply to a loosely packed load. Dressings in particular should not be packed tightly as steam will not penetrate. Wire Mesh Baskets or Dressing Drums are recommended for this application.

When large packs of dressings or large volumes of liquid are being sterilised, it is advisable to allow a further 10 minutes sterilisation time. This ensures adequate penetration of the materials by steam and heat.

Use these times as a general guide only - always use a sterilisation test e.g. the TST integrator strips supplied.

Instruments and Equipment 15 minutes @ 121 deg C
Dressings and Drapes 30 minutes @ 121 deg C
Liquid in Sealed Containers (0ml - 50ml) 20 minutes @ 121 deg C
Liquid in Sealed Containers (50ml - 100ml) 20 minutes @ 121 deg C
Liquid in Sealed Containers (100ml - 200ml) 20 minutes @ 121 deg C
Culture Media (up to 1 litre) 15 minutes @ 121 deg C

Notes on sterilisation of Culture Media:

1 - Always follow the manufacturer's instructions.
2 - Use volumes up to 1 litre.
3 - Use similar volumes in the same load.
4 - After cycle test for sterility.
5 - Check microbiological performance before use.



4 - Maintenance

UK users - this autoclave comes within the scope of 'The Pressure Systems and Transportable Gas Containers Regulations 1989' and should be inspected and maintained accordingly. General maintenance should be carried out by a competent person only, as and when deemed necessary.

4.1 - Lid Gasket - Check the white silicone Lid Gasket for distortion or wear and tear. The Lid Gasket is located in the groove on the underside of the lid. Check that it has not become brittle. Replace the Lid Gasket with a new one if necessary.

4.2 - Body Rim - Check the rim of the body where the Lid Gasket seats for damage to the metal rim which would cause the lid seal to leak. If the damage is only minor then the rim can be repaired by filing and smoothing with emery cloth. Major damage should be referred to the manufacturer or a qualified service engineer.

4.3 - Draw-off Cock - Check the Draw-off Cock for signs of leaking around the seals and from the valve. Replace the seals or complete Draw-off Cock with a new one if necessary.

4.4 - Cleaning - Use normal household detergent to clean the interior of the autoclave.

4.5 - Safety Valve Adjustment and Maintenance - Please see our Safety Valve Adjustment document.

4.6 - Electrical Maintenance (by a qualified Electrician only) - One element is internally fitted - 2.0kW - requiring a minimum 10A fuse. Check that the terminals on the elements are tight and that the elements are securely mounted in the base. Check the Switch and light for damage. Replace if necessary. See that the IEC connector fits firmly in the socket.

4.7 - Overheat Cutout - To avoid damage to the element, should the autoclave boil dry, it is fitted with an automatic overheat cutout. This is clamped to the base of the chamber. If the device should cutout it must be manually reset. Before doing this switch off the mains to the autoclave and remove the plug. Allow the autoclave to cool down. To reset the cutout turn the autoclave upside down and remove the perforated protection plate from the bottom. The cutout will now be visible. It is a round black unit approximately 15mm in diameter with a red button protruding from the middle. To reset the cutout press this red button. You should hear an audible 'click' as the cutout is reset. Refit the protection plate and turn the autoclave the right way up. The autoclave will now work as before.

4.8 - Thermostat Adjustment - The autoclave is controlled by an electronic thermostat mounted in the base. The working temperature is adjusted using a potentiometer mounted on the skirting band. Remove the protective cap to the left of the rating plate to access the potentiometer adjuster. The adjuster is a blue fluted shaft. Bring the autoclave up to working temperature. To increase the working temperature turn the adjuster clockwise and to decrease the set temperature turn the adjuster anti-clockwise. A turn of 30º equates to approximately 5ºC. The autoclave should be left to settle for about 2 minutes after each adjustment. When the desired setting is reached replace the protective cap. The maximum setting allowed is 121ºC.
ST XX28 Illustration A - Draw-off Cock
B - Aircock
C - Pressure Gauge
D - Safety Valve
E - Thermometer
F - Wing Nut (6)
G - Drop Bolt (6)
H - Switch