ASEPTIC TECHNIQUES
OUTLINE
 Definition
 Importance of Aseptic Techniques
 Uses of Aseptic Techniques
 Principles of Aseptic Technique
 Requirements to Achieve Strict Asepsis
 Laminar airflow station
 Protective clothing
 Personnel
 Sources of contamination and prevention
ASEPTIC TECHNIQUES
Aseptic technique means using practices and procedures to prevent
contamination from pathogens. It involves applying the strictest rules to
minimize the risk of infection.
It prevents the access of viable microbial and particulate contamination into
the following products:
 Ophthalmic and parenteral products
 Products sterilized by filtration
 All sterile products’ undergoing sterility testing
The aim of using aseptic technique is to eliminate germs, which are diseasecausing microorganisms
In the microbiology lab aseptic technique is used to:
• Prevent contamination of the specific microorganism we are working with.
• Prevent contamination of the room and personnel with the microorganism
we are working with.
Importance of aseptic
technique
The biggest risk of many medical procedures is the chance for infection. On
average, about 1 in 31 hospital patients has some kind of healthcareassociated infection on any given day.
Your immune system is strong, but many procedures can carry germs into your
body past your normal immune defenses. Aseptic technique is the simplest
and safest way to prevent infection.
It’s designed to keep dangerous bacteria and other microorganisms out of
wounds and protect you from infections when you’re recovering.
USES OF ASEPTIC
TECHNIQUES
In healthcare settings aseptic technique is commonly used in the following
procedures:
 handling surgery equipment
 during vaginal labor
 accessing dialysis catheters
 performing dialysis
 inserting a chest tube
 inserting a urinary catheter
 inserting central intravenous (IV) or arterial lines
 inserting other draining devices
 performing various surgical techniques
USES OF ASEPTIC
TECHNIQUES
Aseptic technique should also be used in situations like:
 when inserting, maintaining or dressing an invasive device, e.g., urinary
catheter, wound drain
 when infusing sterile fluids and medication
 when dressing wounds healing by primary intention, e.g., surgical
wounds, burns
 dressing deep wounds that lead to a cavity or sinus
 minor surgery procedures
 suturing wounds
 vaginal examination using instruments, e.g., smear taking, high vaginal
swab
 if the patient is immunosuppressed, diabetic or at high risk of infection.
PRINCIPLES OF ASEPTIC
TECHNIQUES
The principles of asepsis/aseptic technique are:
 Reducing activity in the immediate vicinity of the area in which the
procedure is to be performed
 Keeping the exposure of a susceptible site to a minimum
 Checking all sterile parts to be used for evidence of damage or moisture
 Ensuring all fluids and materials to be used are in date
 Don’t re-use single used items
 Ensuring contaminated/non-sterile items are not placed in the sterile field
 Ensuring appropriate hand decontamination prior to procedure
 Protecting uniform or clothing with disposable apron
 Use sterile gloves
REQUIREMENTS TO ACHIEVE
STRICT ASEPSIS
 Sterile starting materials
 Sterile equipment
 Controlled environment
 Sterile containers
 Suitable technique by trained personnel
ASEPTIC TECHNIQUES USED
IN PREPARATION OF STERILE
PRODUCTS
a. Laminar Airflow Stations
b. Protective Clothing
c. Personnel
Laminar Airflow Stations
 Laminar airflow is the flow of the entire body of air at the same speed and in
the same direction.
 Laminar airflow station is carefully designed to direct HEPA filtered air. It
provides protection against contamination of objects present in the area of
activity
 It is also used to move air safely through laboratory enclosures. It directs
unrestricted airflow towards sterility, prevents contamination and reduce
potential turbulence
 LAF if properly utilized, is a great asset in providing suitable working
conditions
 It could be vertical or horizontal (VLAF and HLAF respectively)
 It can be used to sweep a working area virtually free from microorganisms
and provides a suitable working environment for aseptic procedures
Protective clothing
 In order to prevent contamination of work area, it is necessary to enclose each
person enclosed in an appropriately designed sterile, impervious clothing.
 These clothing includes: gloves, footwear, headgear, coverall etc.
 Most airborne contamination in a clean room result from personnel using the
facility
 The outermost layer of the epithelial cells is estimated to shed 10(9) cells per day
 Microbes are often associated with whole skin cells or fragments of these cells
 The average size of these bacteria-carrying particles is thought to be about 14
micrometer.
 They will settle in still air under gravitational forces at a rate of about 0.37m/min
 It has been estimated that factory workers can disperse 1000 bacteria-carrying
particles per minute
PERSONNEL
 Number of personnel working in clean area must be low
 Staff must demonstrate high standards of both integrity and motivation
 All personnel should have formal instructions to carry out their functions
 Personnel must be train on procedures to undertake in workplace
 All staff must understand the significance of strict controls imposed
 Compliance with procedures is likely to be increased if the reason for their
imposition is understood by all staff
 Clean room personnel should be encouraged to report any minor infections
or disorders which may render them temporarily unsuitable for aseptic work
and regular medical checks should be made
Operator’s technique
Basic rules for effective aseptic processing are:
1. Use of ‘no touch’ technique wherever possible
2. Reduce air disturbances to a minimum
3. Consider the arrangement of objects under the LAF
4. Refuse to be distracted
5. Use of the laminar airflow cabinet
NO TOUCH TECHNIQUE
Handle small articles with sterile forceps
 Sterile apparatus must be touched, handle as distantly as possible from the
part of the apparatus which will come into contact with a sterile liquid or
solid
 For example, the plunger of a syringe must not be touched because it will
subsequently come into contact with the inner surface of the syringe barrel
and hence with a sterile
 This rule applies even when sterile gloves are worn
REDUCTION OF AIR
DISTURBANCES TO A
MINIMUM
 Standard procedures should be designed to minimize movement of
personnel within the clean room
 Objects should be positioned within reach under laminar airflow cabinet
 Only arms and hands should be placed into the cabinet area
 Operators should not positioned hands between the source of air and the
objects being manipulated
 Sharp and sudden movements should be avoided
 Poor aseptic technique negates the benefits of the LAF cabinet
ARRANGEMENT OF
OBJECTS UNDER LAF
 Clean air should not flow over dirty articles to contaminate sterile articles
 The cabinet should not be loaded with unnecessary equipment
 Materials required should be carefully selected and arranged before
beginning the procedure
 For e.g. placement of large objects in the airstream of a LAF cabinet will
create downstream turbulence in proportion to the size of the object
 If a sufficiently large object is located near the front of a horizontal LAF
cabinet, contaminants from the room or from the operator can be drawn
into the work area behind the obstruction
 Unfortunately a general lack of adherence to the principles outlined above
is quite common
 Such lack of discipline is inexcusable
REFUSE TO BE DISTRACTED
 No interruptions should be allowed until a set procedure has been
completed
USE OF LAMINAR AIRFLOW
CABINET
 The airflow should be switched on and left for 15minutes before use
 The inner faces of the cabinet should be swabbed with a suitable
antimicrobial agent
 An appropriately swabbing sequence is:
• Horizontal LAF- top, sides, work surface
• Vertical LAF- back, sides, front, work surface
• All equipment and articles should also be swabbed before placement in
the cabinet the outer wrapping should be removed fro wrapped items
Operator tests
 Regular tests are done to ensure adequacy of technique of each operator
 These involve serial transfer of a nutrient medium which is subsequently
inoculated and examined for the presence of turbidity indicating microbial
growth
 The test should involve both general transfer techniques and specifics
operations which form part of the operator
Sources of contamination in
aseptic area and method to
prevention
Contamination, in broad sense, is the presence of minor unwanted particulate
matter called contaminants in atmosphere, physical body, etc.
• Right from production to packaging almost every sector of pharmaceutical
industry comes across contamination.
• The most common sources of contamination fall into the following three
main categories:
• Atmospheric contamination
• Fluid contamination
• Transfer contaminants
Atmospheric
contamination
Atmospheric conditions during manufacturing as well as during storage affects
the quality of final preparation.
• Atmosphere in and around the industrial area contains potential
contaminants like dust, silica, etc and gases like CO2 , water vapour, etc.
• Besides the above mentioned contaminants, microorganisms like
P.aeruginosa etc.
These contaminants may get incorporated into the end product either during
the process of manufacturing or during purification.
Prevention of atmospheric
contamination
• Prior to its entry into the working area, the air should be initially passed
through a suitable pre-filter then treated with an electrostatic precipitator
and finally through HEPA filters.
• Periodic removal of air-borne dust settled on walls, floors and ceilings is
essential.
Fluid contamination
• Water is the most common solvent in pharmaceutical industry
• Although, it is deprived of most of the contaminants yet it contains pyrogens
and traces of sulphates, chlorides and carbonates of Ca, Mg and Na.
• Therefore, usage of water for washing the machineries and working areas
may leave traces of these contaminants.
Prevention of fluid
contamination
• Almost all of the pharmaceutical operations should be carried out using
purified water obtained upon deionization, distillation, ion exchange,
reverse osmosis, filtration or other similar processes.
• For the preparation of parenterals, water for injection, sterile water for
injection or bacteriostatic water for injection must be employed.
Transfer contaminants
• Transfer contaminants refer to the contaminants sourced from personnel
and wheels of trolleys used for transport of goods.
• Personnel working in aseptic areas, if suffering from cold, allergies,
dermatological conditions or any similar illness carry multiple microorganisms
which upon expulsion into atmosphere via sneezing, coughing, talking etc.,
can lead to contamination.
• For example, atmospheric dust particles may get entangled with the fibres
of the clothes which can get dislodged due to body movements and lead
to contamination.
Prevention of transfer
contaminants
• Personnel should be well trained and periodically evaluated in the principles
of aseptic processing and techniques to be employed before participating
in the preparation of sterile products.
• Apart from gown, the personnel area also required to put on face mask,
head cap, gloves, foot covers and even goggle to ensure complete
coverage of all skin areas.
• The entrance of most of the working areas is equipped with air blowers that
aid in removing any loose dirt, lint from uniform of the operators.