|
Introduction:
At Machinfabrik, where innovation motivates us each day to move forward,
development of the ethylene oxide sterilizer to meet the increasing demands
of the stringent international standards of ASME, USFDA, EN285, ISO and
HTM 2010, was a target that we had to attain.Because it is toxic and potentially
carcinogenic, the use of EtO is under ever increasing regulatory scrutiny
and control. Which makes the machine requiring a high level of sophistication
and criticality of process control .
With more than 25 successful installations, the ethylene oxide sterilizer
proves its capability to adapt to a variety of products. Non-liquid products,
contained in gas permeable packages not compatible with the heat or dry
heat or steam sterilization, and not compatible with radiation sterilization,
are candidates for sterilization with EtO gas.
Technique:
Ethylene
Oxide (EO) gas permeates packaging and products at relatively low temperatures
and kills micro-organisms by interfering with their protein and DNA. This
process is enhanced by water vapor and therefore control of chamber humidity
is important for effective sterilization
The sterilization cycle can be split
up into 3 different phases:
1. Humidification phase this phase
comprises of vacuum and steam pulsing followed by steam hold which impacts
humidity to the load & this humidity in turn helps the sterilization
process.
2. Sterilization.: the phase includes the injection of the ETO gas mixture
that causes the sterilization of the products.
3. Air wash this stage comprises of mechanical vacuum creation, followed
by pulsing with nitrogen or carbon dioxide gas so as to allow the ETO
GAS to be released via scrubber.
Top
Features:
1.SS.304 chamber design in compliance with ASME section VIII
2.Double gasket provision for safety operation.
3.Jacket heating system in provided to ensure jacket heat up before the
sterilization process and hence ensure uniform temperature uniformity
in the chamber
4.Gas evaporation system is provided to ensure gaseous sterilant even
at low temperature
5.Gas circulation system in place to achieve uniform concentration of
EtO gas. This is imperative for chamber volumes above 3 cubic.meter.
6.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
.
Top
Applications:
Eo sterilizers find typical application for plastic disposables, where
steam sterilization is rendered inapplicable since the temperature ranges
associate with steam sterilization may cause deformation of the product.
EtO is used for a wide range of products including blood oxygenators,
catheters, tracheostomy tubes, mechanical heart valves, sutures, custom
procedure kits, adhesive bandages, tubing sets, and so on.
Top
Optional
Features:
Normally the ETO used for gas sterilization is mixed with dilvents 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).
Depending upon
the concentration of the mixture, two cycles are employed
1. over pressure
cycle for lean mixtures (10 to 20 % ETO)
2. vacuum cycle for rich mixtures (90 to 100 & ETO)
Gas scrubber :
With our strong
commitment to environmental protection and social conciousness we have
developed the gas scrubbing system for converting the ETO gas exhausted
from the chamber to ethylene glycol a bio friendly substance which can
be easily discharged into the sewage.
|