 What is the difference between disinfection and sterilization? Disinfection destroys all the micro-organisms present in a given environment apart from spores: an object that has been disinfected properly may still transmit a pathogenic micro-organism. Sterilization, on the other hand, is the complete elimination of all micro-organisms including spores.
What are the main features of steam sterilization? Heat is the best and most used sterilization agent and pressurized, saturated water vapour is the most efficient method of heat transmission. That is why steam sterilization reduces the time and the temperature needed for the treatment: at 134 °C an exposure of only 4 minutes is sufficient, at 121 °C a time of 15 minutes is enough. In addition, steam sterilization creates no toxic or dangerous residues on objects and does not damage instruments (provided that they can withstand the temperatures reached).
What is EN 13060? This is the applicable European standard, relating to small steam sterilizers. Cominox® has since 1996 been an active member of the WG5 work-group of the European Committee for Standardization's TC 102 technical commission, working on the drafting of EN 13060.
What is a Type-B autoclave? EN 13060 distinguishes between three types of cycle:
B cycle for sterilizing all objects (solid instruments, porous objects and A and B hollow objects, both packaged and un-packaged);
N cycle for sterilizing only un-packaged solid instruments;
S cycle for sterilizing un-packaged solid instruments plus one other of the types indicated for cycle B (to be specified by the maker).
Type B autoclaves are autoclaves that can carry out cycle B and thus can sterilize any kind of object.
What is the sterilization temperature band? EN 13060 lays down that during sterilization the following nine temperatures - eight measured at different points within the load and the unoccupied space remaining in the chamber and the last a reading taken on the saturation vapour curve according to the pressure measured in the chamber - must be above the sterilization temperature, but not by more than 4 °C (e.g. for a cycle at 134 °C the readings must be between 134 and 138 °C, the sterilization range). In addition, there must not be more than a 2°C difference between any one reading and another at any given time. This guarantees that the conditions necessary for sterilization are kept constant and uniform throughout the period of exposure and, by means of a comparison of temperature to pressure on the saturation vapour curve, that the air has been properly removed prior to sterilization.
What are the pre-vacuum phase and any vacuum pulse phase for? These are necessary for the removal of air from the autoclave chamber, given that at any given pressure and temperature the density of air is around 1.5 times that of steam, such that any air present during sterilization settles in the lower part of the chamber and creates so-called "air pockets", where the temperature is not controlled and this is potentially deleterious as far as sterilization quality is concerned.
Why is drying important? With packaged objects drying is vital to guarantee the sterility of the instruments contained in packages while in storage: the packages must be dry when removed from the autoclave at the end of the cycle, otherwise they might immediately become contaminated again.
What is the Bowie & Dick Test for?
Its purpose is to check the degree of steam penetration in the case of porous objects (e.g. gauze or fabric) and the efficiency of the air removal system. The test kit normally consists of treating a package containing a chemical process indicator according to a special sterilization cycle at 134°C for 3.5 minutes. The test is positive if the chemical indicator changes colour in line with the information given by the producer of the test kit
What is the difference between type A and type B hollow loads? According to the definition in EN 13060 type A hollow objects are instruments with an open cavity on only one side where the ratio of length to diameter of the cavity is greater than or equal to 1 and less than or equal to 750 (1 = L/D = 750) and where the length of the cavity is not greater than 1500 mm (L = 1500 mm); or, alternatively, instruments with an open cavity on both sides where the ratio of length to diameter of the cavity is greater than or equal to 2 and less than or equal to 1500 (2 = L/D = 1500) and where the length of the cavity is not greater than 3000 mm (L = 3000 mm). Type B hollow objects, on the other hand, are instruments with an open cavity on only one side where the ratio of length to diameter of the cavity is greater than or equal to 1 and less than or equal to 5 (1 = L/D = 5) and where the diameter of the cavity is greater or equal to 5 mm (D = 5 mm); or, alternatively, instruments with an open cavity on both sides where the ratio of length to diameter of the cavity is greater than or equal to 2 and less than or equal to 10 (2 = L/D = 10) and where the diameter of the cavity is greater or equal to 5 mm (D = 5 mm).
The Cavity diameter (D) / Length (L) chart below shows the areas relating to type A (in blue) and type B (in orange) hollow bodies with an open cavity on only one side (for those with an open cavity on both sides, for any given cavity diameter, double the length to obtain the equivalent diagram). The space above these areas relates to those bodies where the ratio of length to diameter of the cavity is too big for them to be sterilized even with B cycles; the space below relates to bodies that are not hollow but solid.
COMINOX “LCD” Series Sterilisers: 20 Common User Questions / Mistakes COMINOX “LCD” Series Sterilisers: 20 Common User Questions / Mistakes
1. Power must be ON & unit not “OFF” (IE: push “ON” button) when filling water.
Otherwise, unit will not beep &/or provide indication. Water tank overflows to waste tank or bench.
“Waste tank Max” will also occur if unit is overfilled
2. STOP button must be pressed at the end of a cycle.
The chamber is kept locked after an unwrapped cycle to keep the load sterile until it is needed.
3. If an alarm occurs, a card must be put in (or security code entered) to acknowledge & cancel alarm.
Turning power off will not do it. The security code = 1
4. When the unit is “OFF” the 4 keys at the bottom are all labeled as “ON” meaning all four buttons can be pressed to turn the unit “ON”. “Off” is shown in status bar at top.
5. Hollow items such as handpieces should not be processed on "Wrapped" (this is for wrapped solids).
Hollows need to go on the "Porous/Hollow" cycle
6. The purple printer cover must be pressed in on the RHS before opening to release the catch.
Failing to do this can break the latch.
7. When changing paper, it must be thermal with the sensitive side UP as it comes out.
The clear door must be latched closed on both sides or it will not print.
8. The drain tube from the back (Dynamica / B types) must not be kinked or have "U-bends".
Errors will occur if this is not checked.
9. If autofill is used, the reservoir should be 10 litres. (5L bottle = 1.5 fills & errors occur frequently).
10. At least 10 cm clearance behind the unit is required for ventilation & fan outlet.
11. PRINTOUT: “Change Phase” = short printout, “Every Minute” = long printout
12. Cards: Administrator allows access to all functions /// User card is limited to cycles programmed
13. Drain Taps: White(18L) / LHS(24L) = Fresh Tank /// Black(18L) / RHS(24L) = Waste Tank
14. If you drain waste whenever you fill, you won't get starts aborted with "Waste Tank Max".
(Users should ALWAYS check bottom section of screen for any alerts before closing/ pressing start.
15. If you start another cycle too quickly & get "Cooling Pause" then it is much quicker to:
Stop cycle, cancel stop alert, open door to cool for a few minutes (to 80deg), then restart.
BUT, this will change the cycle count.
16. If unit won't turn on, & display is blank, check power is on at wall & power switch (inside printer cover).
17. Do not fill the water without the correct funnel. Water spillage into the control panel / printer may result.
18. Chamber should NOT be cleaned with ANY chemicals without specific approval.
19. Do not install or move the unit without carrying out the leveling procedure in the manual.
This puts the chamber on the correct angle. FLAT is NOT correct.
20. If circuit breaker trips when steriliser is operated, check total load on the circuit.
Another heating appliance such as a kettle is usually the culprit.
More than one power point is normally on one circuit/fuse.
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