Bench Autoclave Standard Operating Procedure For Installation, Use and Maintenance
1. Introduction This SOP is intended for use with the following model, in a laboratory context: Type: Nuve Bench Top Steam Steriliser Model: OT 020 Year: 2006 Max Temp: 140 C Max Pressure: 2.6kg/cm 2 Serial Number: 02-0370 Power: 1450W Fuse: 2x10A AC Mains: 230V, 50Hz For use by authorised persons only 2. Installation and Positioning 2.1 Transporting The autoclave must be supported from underneath and never be inverted. 2.2 Energy requirements The autoclave requires a mains electricity supply of 230V +/- 10%, 50Hz. A supply fitted with a circuit breaker should be used for protection against short circuit, in case of an isolation fault. 2.3 Appropriate conditions Indoor use only Ambient temperature range: 5 C to 40 C Maximum relative humidity: 80% for temperatures up to 22 C. Maximum altitude: 2000m 2.4 Positioning Check that autoclave is stable on four pads Check that positioning is suitable for users; in order that a user can follow up sterilization if working on something else. Ensure free space on either side of autoclave to allow functioning of air vents. Ensure space behind autoclave to allow access to ON button (Figure 1.) and Pressure SAFETY VALVE (Figure 7.) 3. Preparation for Use 3.1 Filling with Distilled Water Plug in to a suitable mains electricity supply and switch on the autoclave (Figure 1.) Ensure that the control panel activates. Using the funnel provided, fill with distilled water* until the Max Water Level LED lights up. The tank holds a volume of 5 litres. (Figures 2,3) Do not continue filling with water after the Max Water Level LED has lit up. When this level is reached an alarm will sound. This can be deactivated by pressing the button shown. (Figure 4.)
*Note : Use distilled water only. The use of any other type of water may cause expensive and irreversible damage to the heaters. This is considered improper use of the autoclave and damage will not be covered by warranty. The water must be changed weekly, or re-filled when the Min Water Level LED lights up (Figure 3.) Figure 1. Green ON switch at rear of autoclave Figure 2. Using the funnel to fill the autoclave at the water inlet located at the back, right hand corner. Figure 3. Control panel showing water level warning LEDs and ALARM STOP key. ALARM STOP key Max water level LED Min water level LED 3.2 Preparation of Samples Attach sterilisation indicator tape to each sample, to validate the sterilization. Ensure that the indicator tape is the correct type for a steam sterilizer, by checking the centre of the roll. Ensure that samples will not overflow, become deformed or fall over during sterilisation, by using appropriate racks. Lids on containers must be fastened loosely to prevent breakages 4. Operation Load samples, ensuring a distance of 2.5cm between each sample, and between samples and chamber walls, to allow efficient circulation of steam
Add data logger to chamber if required Close the door and tighten until the Lid Open LED switches off. Enter each cycle into the LOGBOOK Set a program as detailed below 4.1 Programming 4.1.1 Setting the Temperature Push the TEMP SET Key and ensure that the green LED on the key lights up Set the sterilisation temperature by pushing the VALUE INCREASE or VALUE DECREASE keys. Immediately push the TEMP SET key again to save the set value (Figure 4.) 4.1.2 Setting the Time Push the TIME SET key and ensure that the red LED on the key lights up. Set the sterilisation time by pushing the VALUE INCREASE or VALUE DECREASE keys Immediately push the TIME SET key again to save the set value. (Figure 4.) When the program is set, push the START key Figure 4. Keys used for setting a sterilisation program Temp set key Time set key Start key Value increase/decrease keys 4.2 The Sterilisation Cycle The cycle consists of the following phases; an LED will light up to denote the current phase: (Figure 5.) Temperature display Time display Figure 5. Green LEDs showing the current phase of the sterilisation cycle Water filling Preparation Sterilisation Steam discharge Drying Cycle ended
4.3 Opening the Chamber When the CYCLE ENDED LED lights up, (Figure 5.) the door lock is released An alarm will sound when the cycle is complete, this can be stopped by pressing the ALARM STOP key (Figure 3.) Ensure that the sterilisation chamber manometer reads ZERO before you attempt to open the door. (Figure 6.) If the manometer shows a value other than zero, open the SAFETY VALVE to discharge the steam from the sterilisation chamber before opening the door. (Figure 7.) Figure 6. Manometer, or pressure gauge Figure 7. Location of pressure safety valve at rear of autoclave Important: The door should not be opened until the temperature display (Figure 5.) reads less than 90 C. The door should be opened carefully, with the door between the operator and the chamber opening, in case of residual pressure (Figure 8.) Figure 8. Correct procedure for opening the chamber door Ensure that the indicator tape has developed dark lines (Figure 9.) Figure 9. The difference which should be observed with indicator tape before (left) and after (right) sterilisation
Samples should be handled with caution immediately after sterilisation as the contents may remain at high temperatures The loosely fastened lids of sterilised samples should be tightened as soon as the chamber is opened, to avoid contamination from the atmosphere. 5. Maintenance and Cleaning 5.1 Periodic Maintenance Replace the sterilisation chamber lid gasket ONCE A YEAR. (Contact Nuve technical service) Change the distilled water in the water tank ONCE A WEEK, by draining it from the outlet at the front with the supplied tubing. (Figure 10.) Figure 10. Emptying water tank by attaching specific tubing to water outlet An alarm will sound when the tank is empty. This can be stopped by pressing the ALARM STOP key (Figure 3.) 5.2 Cleaning Important: Disconnect the power from the mains supply before cleaning Remove the inner grill by unfastening the bolt with an appropriate spanner or wrench (Figure 11.) Carefully clean beneath the heating element with a flexible brush (Figure 12.) Wipe the sterilisation chamber gasket and inner surface with a damp cloth (Figure 13.) Mild liquid soap may be used to remove persistent dirt and dust Clean and replace the inner grill Check the chamber before each use, and clean if necessary Do not use any other detergents or chemicals on the inner surface or chamber door Enter in logbook Figure 11. Figure 12. Figure 13.
6. Troubleshooting 6.1 If the autoclave fails to operate, check that: The On/Off switch is on The mains electricity supply is functioning The plug is properly plugged in to the mains supply The plug itself is not defective The fuses are not defective The plug socket is not defective 6.2 If the autoclave does not heat, check that: The sterilisation temperature is set The program has been started 6.3 If the pressure does not rise appropriately, check that: The safety valve is not open 7. Useful Spare Parts and Essential Requirements Distilled water availability Rubber tubing to drain water tank, with appropriate fixture to fit outlet Funnel for filling water tank, with appropriate width to fit inlet 10 amp fuses Spanner or wrench to undo bolt on inner grill Spare bolts for inner grill Cleaning equipment: mild detergent, soft cloth, flexible brush Log book