Biosafety is the application of safety precautions that reduce a Laboratory based risk of exposure to a potentially infectious material and limit contamination of the working and surrounding environment. The primary principle of biosafety is “Containment”. Containment The action of keeping harmful things under control and within limits Or A series of safe methods for managing infectious bacteria in the laboratory.

1. Biosafety
Biosafety is the application of safety precautions that reduce a Laboratory based
risk of exposure to a potentially infectious material and limit contamination of the
working and surrounding environment.
The primary principle of biosafety is “Containment”.
Containment
The action of keeping harmful things under control and within limits
Or
A series of safe methods for managing infectious bacteria in the laboratory.

2. Levels of containment
Primary containment
Protects people and the immediate laboratory environment from exposure to
infectious agents.
Good microbiological techniques and safety equipment provide good primary
containment.
Secondary containment
It protects the environment external to the laboratory from exposure to infectious
materials.
Good facility and operational practices provide secondary containment.
Separate working are, decontamination facilities, hand-washing facilities, special ventilation systems and
airlocks are examples of barriers used for secondary containment.
Containment

3. Containment
Elements of containment
• Laboratory practices
• Safety equipment
• Facility design

4. Biosafety levels
• Biosafety level 1 (BSL-1)
• Biosafety level 2 (BSL-2)
• Biosafety level 3 (BSL-3)
• Biosafety level 4 (BSL-4)

5. BSL-1
BSL-1 is suitable for work involving agents that do not cause diseases and present
minimal potential hazard to laboratory personnel and the environment.
They are ideal for promoting good microbiological techniques as they are basic and
essential to laboratories of all levels.
Work is conducted on bench tops using standard microbiological practices. Special
containment equipment or facility design is not required.
Laboratory personnel must have specialized training and be supervised at all times in
the laboratory. Moreover, it is essential that all staff go through health checks and have
their medical history recorded

6. BSL-1

7. BSL-2
BSL-2 is suitable for work involving agents that pose moderate hazards to personnel and
the environment.
• Laboratory personnel should have specific training in handling the hazardous agents
and are supervised.
• Access to the laboratory should be restricted when work is being conducted
• All procedures in which infectious aerosols or splashes may be created should be
conducted in biosafety cabinets.
• Laboratory personnel must be provided medical surveillance which is necessary.
• Laboratory equipment should be routinely decontaminated.
A laboratory safety manual should be available to identify potential hazards and state
the procedures to eradicate these hazards.

8. • Lab coats and gloves must be worn while performing work. Do not take lab coat
outside the lab.
• Hands must be washed before and after the work in the lab.
• Safety goggles must be worn when working with acids, ultraviolet radiation and
objects that might injure the eyes, i.e. sharps.
• Open-toed sandals or slippers must be avoided.
• Eating, drinking, smoking, applying cosmetics and contact lenses are not allowed in
the laboratory.
• Food must not be stored in laboratory fridge.
• No mouth pipetting
• Limit the use of hypodermic needles. They should not be used for pipetting or for
any other purposes except for injections and aspirations of fluid from animals.
• All spillages must be reported to laboratory supervisors.
• All contaminated items must be decontaminated before getting disposed of.
• There must be a written procedure for all decontamination and spillages.
BSL-2

9. BSL-2

10. Biosafety Level 3 laboratory is designed and provided for work with severe risk
microorganisms or with large volumes of moderate risk microorganisms (handled in BSL-
2) which might lead to aerosol spread. Like Bacillus Anthracis (Cause anthrax disease)
All the working instruction of BSL 1 and 2 also apply to BSL 3 but some additional
protective measures must be taken.
BSL-3

11. Protective measures
• The international biohazard warning sign, along with BSL level and supervisor name,
must be displayed on the doors of the laboratory.
• Laboratory protective clothing must be of solid-front of wrap-around gowns, scrub suits,
head coverings and if necessary, shoe covers.
• Front-buttoned laboratory coats and those that do not fully cover the forearms are not
suitable.
• Laboratory coats after use must be decontaminated before washing.
• Changing into laboratory clothing is necessary when working with certain agents (for
e.g. zoonotic agents). A complete change of clothing may be necessary before entering
and after leaving the laboratory.
• Infectious agents must be handled in biosafety cabinet
• Respiratory protective equipment may be necessary, depending on the procedure.
• All staff must undergo health checks and be provided with a medical contact card as
proof that they are employed in an institute and/or company with a containment
laboratory.
BSL-3

12. BSL-3

13. BSL-4
Biosafety Level 4 laboratory also known as the maximum containment laboratory, is
specially designed for the handling of microorganisms which are of unknown
pathogenicity or could be lethal. Like Ebola virus
The practices and procedures in the laboratory are required for work with dangerous
agents which cause life-threatening diseases which have no vaccines or cures.
It requires maximum containment and needs to be located at an isolated building with
specialized ventilation and waste management systems.

14. BSL-4
Two models
• Class III cabinet lab
Handling of agents must be done in a Class III biosafety
cabinet. Exhaust air from the Class III BSC must pass through
two HEPA filters prior to release to external environment.
• Suit lab
Dedicated room air supply and exhaust systems are
required. An one-piece positive pressure supplied air
protective suit must be worn by the laboratory personnel.

15. BSL-4

16. BSL-4

17. • Entry must be limited by a secure, locked door. A means of documentation of persons
entering and leaving the laboratory must be maintained.
• No one should work alone in the lab, a two-person rule should apply.
• An inner disposable pair of gloves must be worn to prevent tears in the outer pair of
gloves.
• A method of communication for emergency contacts must be developed between the
staff working in the laboratory.
• There must be a controlled air system - negative pressure maintained in the laboratory.
• A double-door, pass-through autoclave must be readily available for the materials
passing out from Class III Biosafety cabinet.
• A chemical shower must be provided for the decontamination of the positive pressure
suit before the staff leave the laboratory.
• A separate detailed work manual and an emergency programme should be developed.
BSL-4