A general Microbiology that help people to learn understand and matter of Microbiology and basic entities

1. UNIT-IV
GENERAL MICROBIOLOGY

2. CONCEPT OF LAMINAR FLOW
• The principle of laminar flow cabinet is based on the laminar flow of air through
the cabinet.
• The device works by the use of inwards flow of air through one or more HEPA
filters to create a particulate-free environment.
• The air is taken through a filtration system and then exhausted across the work
surface as a part of the laminar flow of the air.
• The air first passes through the filter pad or pre-filter that allows a streamline flow
of air into the cabinet.
• Next, the blower or fan directs the air towards the HEPA filters.
• The HEPA filters then trap the bacteria, fungi and other particulate materials so
that the air moving out of it is particulate-free air.
• Some of the effluent air then passes through perforation present at the bottom
rear end of the cabinet, but most of it passes over the working bench while
coming out of the cabinet towards the face of the operator.
• The laminar flow hood is enclosed on the sides, and constant positive air pressure
is maintained to prevent the intrusion of contaminated external air into the
cabinet

4. REQUIREMENT OF -BSL
• A biosafety cabinet (BSC) is a primary containment
device used with biological material. While handling
biological agents, it is the biological equivalent of using
hazardous chemicals inside a fume hood. Like a
chemical fume hood, a biosafety cabinet protects the
user from hazardous material using directional air
flow. Biosafety cabinets differ in that the air is also
HEPA filtered, which removes biological contaminants.
• The most common cabinet is the Class II Type A2
biosafety cabinet, though there are many other types
of ventilation equipment

6. WORKING & CLASSIFICATION
• The primary purpose of a BSC is to serve as a means to
protect the laboratory worker and the surrounding
environment from pathogens. All exhaust air is HEPA-
filtered as it exits the biosafety cabinet, removing
harmful bacteria and viruses.
• This is in contrast to a laminar flow clean bench, which
blows unfiltered exhaust air towards the user and is not
safe for work with pathogenic agents. Neither are most
BSCs safe for use as fume hoods.
• Likewise, a fume hood fails to provide the environmental
protection that HEPA filtration in a BSC would
provide. However, most classes of BSCs have a secondary
purpose to maintain the sterility of materials inside.

8. SAFETY REQUIREMENT IN MICROBE
LAB
• To avoid contamination and the risk of personnel exposure, the CDC
advises investigators to follow best practices to reduce and control
splatter and aerosol generation, such as keeping clean materials at
least 12 inches from aerosol-generating activities and arranging the
work flow "from clean to contaminated".
• In particular, open flames, not necessary within the clean
environment of a Class II or III BSC, cause disruption of the airflow
inside. Once work inside a BSC has been completed, it is necessary
to decontaminate the surfaces of the BSC as with other lab
equipment and materials.
• When a BSC is serviced or relocated, including replacement of HEPA
filters, it must be gas decontaminated. Gas decontamination
involves filling the BSC with a poisonous gas, most
commonly formaldehyde gas

9. GOOD MANUFACTURING PRACTICES
• Manufacturing facilities must maintain a clean and hygienic
manufacturing area.
• Manufacturing facilities must maintain controlled environmental
conditions in order to prevent cross-contamination from
adulterants and allergens that may render the product unsafe for
human consumption or use.
• Manufacturing processes must be clearly defined and controlled. All
critical processes are validated to ensure consistency and
compliance with specifications.
• Manufacturing processes must be controlled, and any changes to
the process must be evaluated. Changes that affect the quality of
the drug are validated as necessary.
• Instructions and procedures must be written in clear and
unambiguous language using good documentation practices.
• Operators must be trained to carry out and document procedures.

10. • Records must be made, manually or electronically, during
manufacture that demonstrate that all the steps required
by the defined procedures and instructions were in fact
taken and that the quantity and quality of the food or drug
was as expected. Deviations must be investigated and
documented.
• Records of manufacture (including distribution) that enable
the complete history of a batch to be traced must be
retained in a comprehensible and accessible form.
• Any distribution of products must minimize any risk to their
quality.
• A system must be in place for recalling any batch from sale
or supply.
• Complaints about marketed products must be examined,
the causes of quality defects must be investigated, and
appropriate measures must be taken with respect to the
defective products and to prevent recurrence

12. ISO
• The International Organization for Standardization (ISO) is
an international nongovernmental organization made up of
national standards bodies; it develops and publishes a wide
range of proprietary, industrial, and commercial standards
and is comprised of representatives from various
national standards organizations.
• The organization's abbreviated name—ISO—is not an
acronym; it derives from the ancient Greek word ísos,
meaning equal or equivalent. Because the organization
would have different acronyms in different languages, the
founders of the organization decided to call it by the short
form ISO.

13. NABL-CONCEPT
• The National Accreditation Board for Testing and
Calibration Laboratories (NABL) is an autonomous body
under the guidance of the Dept. Of Science & Technology,
Govt. of India whose purpose is to provide accreditation to
testing and calibration of clinical laboratories in the
country.
• It is the sole accreditation body authorized by the Govt. of
India that provides a third-party assessment of quality and
technical competence of labs. NABL also shares links with
Asia Pacific Laboratory Accreditation Cooperation and
International Laboratory Accreditation Cooperation.
• NABL accreditation is recognized and valid through all the
major economies of the world, and by all regulators in
India.

14. • Assurance of genuine reports from accurately
calibrated testing
• Confidence in personnel performing tests
• Elimination of the need for re-testing thereby
saving money & time
• Satisfaction from the services provided

15. DEPARTMENT OF MICROBIOLOGY
AYUSHI SHARMA
MJPRU