Dr . Ashraf Selim
DC , IC&P
Member in IFIC , ESIC , EDA
General Planning Concepts
SPD is the first line of defense against harmful microorganisms.
Contamination prevention is achieved by closely monitoring
the following elements:
1. Air Flow: To minimize microorganism movement from dirty
to clean areas. In clean areas there is a positive air flow.
2. Staff Flow: Personnel work either on the clean side or the
dirty side of the SPD unit to avoid cross contamination.
3. Work Flow: Refers to the movement of clean (sterile)
supplies and the return of contaminated items for
decontamination and sterilization.
1. There shall be a changing area include shower facilities, toilet
facilities and lockers in proximity to the decontamination area.
2. Access to the wash room and to the clean room shall be
through separate dedicated gowning rooms provided with
hand hygiene facilities.
3. The finishes on the walls and other surfaces shall be flush,
smooth, non-linting, water resistant and able to withstand
4. Floors shall be covered in a washable non-slip material which is
7. There shall be adequate lighting.
8. All work surfaces, fittings, fixtures and furniture shall
be made of easily cleanable and disinfected .
9. The workstations shall be of adequate size to
accommodate the wrapping material to be used and
shall be height adjustable.
10. There shall be adequate space between workstations
for equipment and staff movement.
The environmental parameters
a) The ACH shall be at least 10 times per hour.
b) The Humidity should be 35-70 %.
c) The temperature should be maximum 18 - 22 °C.
d) The air pressure must be Negative in relation to the
surroundings in Dirty zone and Positive in clean and sterile /
e) The overpressure should be 10 -15 Pa.
f) The overpressure shall be measured at least once a year
Point Of Use
Transport contaminated instruments to the processing area in a
manner that minimizes the risk of exposure to persons and the
• Use a rigid, leak-proof container.
• Use appropriate personal protective equipment.
Principles and methods of cleaning
Factors involved in cleaning action :
1. Chemical energy: detergent , enzymatic detergent
2. Mechanical energy: friction
3. Thermal energy
Steps: Sorting, soaking, washing, rinsing
a) All items should be dismantled before cleaning.
b) Soaking in detergent for 10 min.
c) Thorough brushing with soft brush with long handle
keeping the brush below the surface of water
d) Rinsing with warm water
Disadvantages of manual cleaning
1. Not effective enough.
2. No Standardization.
3. Subject HCWs to injury from handling sharp
4. Cause minute scratches to the instruments.
5. Brushes must be disinfected after each use.
Ultrasonic cleaning (The microscopic "brush“)
It is like brushing at a speed higher than the vibrations of sound. It
has the advantage that the cleaning action can take place at any
location in or on an instrument where water can reach.
An ultrasonic cleaner works mostly by energy released from the
collapse of millions of microscopic cavitations near the dirty
The bubbles made by cavitations collapse forming tiny jets
directed at the surface.
Never use Ultrasonic cleaner with
Elastic materials: rubber ware and materials of silicon.
Aluminum foil test or Chemical indicator for checking cavitation
Drying of instruments
Drying reduces the risk of re-contamination.
Residual moisture interferes with the sterilization process, and
can damage instruments.
Following any method of cleaning (pre-cleaning, manual,
mechanical and ultrasound) instruments need to be dried.
Drying cabinets should be used for drying instruments
operating temperatures shall be within the range 65°C to 75°C.
Hot air drying may also occur during the last stage of the cycle
of washer/disinfector machines.
After completion of the cleaning process
instruments must be dried then inspected.
1. Visually to ensure the process of cleaning.
2. Functional Inspection: Instruments must be
inspected for working performance.
Packaging of instruments
Packaging materials (e.g., wrapped or container systems)
allow penetration of the sterilization agent and maintain
sterility of the processed item after sterilization.
Materials for maintaining sterility of instruments during
transport and storage include wrapped perforated
instrument cassettes, peel pouches of plastic or paper, and
sterilization wraps (which can be either woven or unwoven).
1. Soft/flexible packaging materials /disposable.
2. Rigid packaging systems / reusable either Drums
Papers including bleached crepe paper and wraps combining
cellulose and synthetic fibers are commonly used packaging
materials for steam, dry heat and ethylene oxide sterilization.
They are permeable to steam, air and chemical vapors and provide
an effective barrier if the packs are stored in clean, dry conditions.
Paper is unsuitable for use in the hydrogen peroxide
plasma method of sterilization as it absorbs the
hydrogen peroxide vapor from the chamber space, thus
interfering with subsequent generation of hydrogen
peroxide plasma during the cycle.
Hydrogen peroxide plasma
Only purely synthetic packaging materials (Tyvec) can be
used in hydrogen peroxide plasma sterilization.
Laminated film pouches
Primary packaging for individual instruments or small
The pouches consist of a sheet of paper or non-woven and a
sheet of laminated transparent plastic, which are sealed
The film cannot be penetrated by steam or air. Removal of air
and penetration of steam is through the paper/non-woven.
1. Air removal and steam access through filters or
valves. They ensure maintenance of sterility
2. They provide an effective mechanical
protection during handling and transport
3. Labeling system offers clear identification of
the content, production data etc.
4. A tamper protection device shall give clear
indication whether a container was opened
1. Where heat seal packaging is to be used, a rotary heat
sealer shall be provided.
2. The heat sealer shall be validated and tested daily to
verify the efficacy of the seal.
Rigid containers should not be stacked.
Trays of surgical instruments should be placed flat on
the sterilizer shelf so that the position of the
instruments within the trays can be maintained.
Textile packs should be placed in the chamber so that
the content folds are at right angles to the sterilizer
shelf to enhance the process of conditioning.
Store instruments in a clean, dry environment in a manner that
maintains the integrity of the package
The physical storage conditions are designed to maintain the
sterility of processed items in relation to temperature, relative
humidity, ACH, and relative pressure
Storage shelves: 18 inches from ceiling
8 – 10 inches from the floor
At least 2 inches from outside wall
Time related protocol / (first in, first out )
For many years a sterile storage time of four weeks has been the
tradition, followed by recall, repacking and reprocessing of all
facility manufactured stock not used within four weeks of
sterilization. (1983. )
The product should remain sterile until some event causes the
item to become contaminated (e.g., a package becomes torn or
The CDC currently makes no shelf-life recommendations for
“Knowing is not enough; we
Willing is not enough; we