4 Function
03/2007
20
DA0621_a/
especially in maximum-containment laboratories
1)
. The entire filter housing is itself
sterilized during each sterilization cycle and is therefore protected from
contamination.
If another sterilizer expansion option requires a sterile air filter (Types FS, FL), the
sterile air filter will be present in the form of a combination filter Types FA/FS,
FA/FL, or FA/FS/FL. This combination filter serves two functions simultaneously:
sterile venting and exhaust air filtration. Sterile venting prevents pathogens from
entering the sterilizing chamber during pressurized aeration at the end of the
sterilization cycle or during aeration at the end of a vacuum drying phase. The
combination filter is also itself sterilized during each sterilization cycle.
4.3.2 Thermolock
The steam sterilizer is equipped with a
thermolock
2))
as safety feature. The
thermolock prevents any opening of the sterilizing chamber as long as the
reference temperature remains above 90 °C
3)
. The thermolock is effective in all
Liquids programs. The current values display (13) shows the reference
temperature for checking (instead of the media temperature) during the cooling
phase. During sterilization, by contrast, the reference temperature is not shown (- -
-).
The sterilizer may be equipped additionally with a flexible temperature sensor
(media temperature control expansion option). This flexible temperature sensor
has a pressure-sealed entry point through the back wall of the sterilizing chamber.
In all Liquids programs, the flexible temperature sensor measures media
temperature as the reference temperature. This temperature is the input value for
controlling the thermolock. The media temperature is continuously displayed in the
current values display (13).
The program steps door locking, heating and automatic deaeration, sterilizing, and
cooling are performed automatically. As soon as the liquid temperature drops
below 90 °C, the thermolock is turned off. The program is terminated, and the door
can be opened.
In case of a power failure or if no electrical outlet is available, the thermolock will
always remain switched on. The door is
locked
. It can only be opened when power
is restored. The door is also locked when the thermolock is active, but the flexible
temperature sensor is defective.
1)
Genetic Engineering Safety Regulations dated March 21, 1995 (A II 2.): “For all operations during
which aerosols could be produced, these must be prevented from reaching the work area.”
2)
Temperature-controlled safety system for liquids to prevent retardation of boiling in accordance with
TRB 402 (3.2.4.), AD instruction A5, DIN 58 950 and DIN 58 951.
