Ethylene Oxide (ETO) sterilizer
is mainly used to sterilize medical and pharmaceutical products that cannot
support conventional high temperature steam sterilization - such as devices
that incompany electronic components, plastic packaging or plastic
containers. Normally the ETO used for gas sterilization is mixed with
diluents such as carbon dioxide or nitrogen in different proportions from 10
% ETO to 90 % ETO. The commonly used gas concentration in the
sterilizers is 450 to 1000 mg/lit of chamber volume (measured as pure ETO).
Emission Control Equipment
- Single or double door With Sliding or Hinged door options to suit
client specific requirements.
- Dimple steam Jacketed for better Uniformity of the heat Distribution.
(Technology for fast Sterilization cycle and low cost operating)
- Gas evaporation system is provided to ensure gaseous sterilant even
at low temperature
- Gas circulation system in place to achieve uniform concentration of
ETO gas. This is imperative for chamber volumes above 3 cubic.meter.
- Gas detection system is provided as a safety measure for ETO gas at
minimum 3 locations to detect ETO leakage and set an audiovisual alarm.
- *Acid Base Scrubbers
- *Catalytic Oxydizers
Sterilization Process Temperature and Relative Humidity Recorders
Fully Automatic PLC with Touch screen Control with all Parameter Online
Printing facility, Computer Interface Facility with software and remote
Contamination Seal to prevent cross-flow of air between the clean and
Sizes available from 100 lts. to 20000 lts.
Most ETO sterilization lines involve three different stages. These can be
separated into three different cells depending on the size or amount of
devices to treat:
PRE CONDITIONING STAGE
- Pre Conditioning
First, products need to go through a pre conditioning phase to make micro
organisms grow. The batch load goes through a dwell time under a controlled
Then the load goes through a long and complex sterilization cycle.
Requirements of such a system are:
- Accurate temperature control.
- Availability of the control system.
- Accurate pressure and vacuum control.
- Easy displays of process phases
- Dedicated customer recipes.
- Auto batching release through tolerance tests.
- Security interlocks between actuators.
- Shut down strategies.
During this cycle, accurate temperature control is important and a heating
jacket is used. As the overall duration of the cycle is depend upon the
Product to be sterilised and ETO Concentration used.
After the doors have been sealed correctly, the cycle can be started either
automatically. If any problem with door sealing is detected the cycle is
interlocked and cannot start.
Once the cycle is started, easy to use displays:
- The actual phase of sterilization
- All the key set points and tolerances as loaded by the recipe
- All the key process values for the auto batch release facility
Control of vacuum and pressure is also required. Due to the toxic effect of
EtO, water ring rotary pumps are used. The vacuum process needs to perform
the emergency evacuation phase for a fast evacuation of gas.
The sterilization phases are :
- Cycle start delay to enable the system to start in stable conditions
- General cell temperature check
- Initial vacuum phase
- Leak rate test
- First flush
- Second flush
- DEC (Dynamic Environmental Conditioning)
- ETO gas injection
- Sterilization dwell time period under ETO
- Post dwell vacuum level
- First wash
- Second wash
- Final air admission
- Final chamber re-evacuation delay
During execution of these phases a batch report is generated. This report
will include: tolerance checks, phase changes, alarms, events and critical
process values. A key feature of the system is auto batch
release. During the sterilization cycle if any abnormal condition occurs,
the batch will be automatically stopped and condition(s) causing the
stoppage will be identified. With this auto batch release
facility operators do not have to wait until the end of the cycle and spend
time going through the batch report to understand why it went wrong. With
this feature, provided that batch is completed satisfactory it will be
automatically forwarded to the degassing room without human varification of
tolerance, process values and alarms.
For each batch the operator selects appropriate product recipe. After
recipe has been downloaded, the operator can verify values are correct for
this particular batch before starting the cycle.
When the batch is over an automatic print of the report can be performed.
Finally, products need to go through a degassing phase to remove any
particle of ETO.
In compliance with :
cGMP, GAMP, ISO 9001 : 2008