Aseptic technique: Environment Flashcards
What is the principle for premises and equipment that must be followed for sterile products?
- Their layout and design must aim to minimize the risk of errors and permit effective cleaning
- Maintenance in order to avoid cross-contamination, build-up of dust or dirt and, in general, any adverse effect on the quality of products
What is the principle for manufacturing that must be followed for sterile products?
- Minimise risks of microbiological contamination, and of particulate and pyrogen contamination
- Quality Assurance bears a particularly great importance and this type of manufacture must strictly follow carefully established and validated methods of preparation and procedure
Where should the manufacture of sterile products be carried out?
In clean areas
What are the FOUR environmental manufacturing requirements for sterile products?
- Air Filtration
> HEPA filter = clean air production
> Classification of cleanroom
2. Air flow pattern control
> Laminar air flow
> Non-laminar air flow
3. Clean workstation
> Clean workstation
> Isolator (in hospital pharmacy)
4. Clean area design
> FRED
> Contamination control
What is required for a room to have when personnel is entering in an out of?
airlocks –> segregates cleanliness zones
How should air be passed through?
Through filters of an appropriate efficiency
- ISO 7 has a better quality of air than ISO 8
What is a high-efficiency particulate air (HEPA) filter? What is the filtration efficiency and what diameter is it at?
A disposable, extended-media, dry-type filter in a rigid frame having minimum filtration efficiency of 99.97% for nominal 0.3-micron diameter
What are the three WAYS a HEPA filter may stop particles?
- Interception
- Impact
- Diffusion
What are the types of airborne particles? Give some examples.
Be organic or inorganic, viable or non-viable
- bacteria, spores, and viruses that are contained in the air
What is the range of airborne particles?
- Range in size from 0.001 micrometer to several hundred micrometers
> Aerosolised particles tend to settle out at a rate depending on the size and density of the particle
For sources of contamination;
A) What are some external sources
B) What are some internal sources
A)
- Atmospheric contamination / air pollution
- Brought in primarily through the air-conditioning system
- Infiltrate through doors, windows, cracks within the structure
B)
- People
- Activity of service equipment
- Every activity involving friction of surfaces
- Dynamic situation in the air
> people working
> fans blowing
> machine in operation
Rooms are divided into classes or grades based on these numbers
- Class 3.5; 350; 3500 [Standards Australia]
- Class 5; 7; 8 [ISO 14644 Standards]
What does a smaller ISO class mean?
- The smaller the ISO class, the better. There are fewer particles in the room.
- The same thing applies to class 3.5, class 3.5 will have fewer particles than class 3500
Air should be directed to obtain the cleanest air in the critical work areas. What does this result in?
- Introduction of large quantities of air at low velocities into the clean space
- In unidirectional movement, usually downward or across the room, prior to removal from the space
As contaminants are entrained, they are conveyed downstream of work zones in the room for dilution or removal or both
What is lamina airflow? How does it involve the HEPA filtered air?
An airflow in which the entire body of HEPA filtered air within a defined area moves in a uniform and unidirectional manner
> one direction
Which room has the highest pressure denoted by the number of plus signs in a diagram?
Cleanroom has the highest pressure
What is non-laminar flow? How does it involve HEPA filter?
Air is supplied through ceiling-mounted HEPA filter(s), flows generally downward, and is removed near the floor level at points remote from the ceiling-mounted HEPA filters
What is the cleanroom? What does it minimize? What parameters are controlled?
Room in which the concentration of airborne particles is controlled
- Minimise the introduction, generation, and retention of particles inside the room
- Temperature, humidity, and pressure, are controlled as necessary
What is a clean zone? Does it have to be located in a cleanroom?
Dedicated space in which the concentration of airborne particles is controlled, and which is constructed and used in a manner to minimize the introduction, generation, and retention of particles inside the zone, and in which other relevant parameters, e.g. temperature, humidity, and pressure, are controlled as necessary
> This zone may be open or enclosed and may or may not be located within a cleanroom
What is a clean workstation? What is it characterized by? Does it have to be placed in a clean room?
Also known as LAMINAR AIR FLOW WORKSTATION (LAFW) (ISO CLASS 5)
An enclosure with a work zone which provides a controlled environment for the protection of products from contamination but which does not provide personnel or environmental protection
- characterized by having its own air filtration system and motor blowers which supply filtered, laminar flow air in the work zone.
- Has to be placed in a clean room
What is the difference between class I and class II biological safety cabinets?
Biological safety cabinets: protect personnel and environment from pathogens, used for working with materials that may or may not be contaminated with pathogens/cytotoxic drugs
Class I
- Receives air from outside
- Doesn’t go through HEPA filter
- PRODUCT WONT BE PROTECTED
Class II
- Has filter
- PRODUCT WILL BE PROTECTED
What are isolators? What are they used as an alternative to?
Isolators are widely used in hospital pharmacy departments as an alternative to cleanrooms for the small scale aseptic processing of sterile products
What is a flow-regulated environment design (FRED) cleanroom? What type of airflow does it use?
- Non-laminar flow
- Incorporating diagonal airflow patterns and forming the secondary barrier for a laminar flow workstation or safety cabinet (double barrier concept)
- Stops airflow to stop particles from a spill leaving
