Health and Safety in the
Laboratory
Safety in Microbiological and
Biomedical Labs
Standard Practices – All Levels
 1.
Lab access limited.
 2. Hand washing required.
 3. No eating, drinking, smoking, handling of
makeup or contact lenses…
 4. No pipetting by mouth.
 5. Policies for the safe handling of sharps are
instituted.
Standard Practices – All Levels
6. All procedures are performed carefully to minimize the
creation of splashes or aerosols.
 7. Work surfaces are decontaminated at least once a day
and after any spill of viable material.
 8. All cultures, stocks, and other regulated wastes are decontaminated

before disposal by an approved decontamination method such as
autoclaving. Materials to be decontaminated outside of the immediate
laboratory are to be placed in a durable, leakproof container and closed for
transport from the laboratory. Materials to be decontaminated outside of
the immediate laboratory are packaged in accordance with applicable
local, state, and federal regulations be fore removal from the facility.
Standard Practices – All Levels
9. A biohazard sign may be posted at the entrance to the
laboratory whenever infectious agents are present. The
sign may include the name of the agent(s) in use and the
name and phone number of the investigator.
 10. An insect and rodent control program is in effect (see
Appendix G).

Laboratory Biosafety Level
Criteria
Levels
1-4 in increasing level of risk
Biosafety Level 1 (BSL-1)
 Agents
not known to consistently cause disease in
healthy adult humans.
 Standard
 Special
Practices are applied (see previous)
Practices - none
Biosafety Level 1 (BSL-1)
Safety Equipment (Primary Barriers)




1. Special containment devices or equipment such as a biological
safety cabinet are generally not required.
2. It is recommended that laboratory coats, gowns, or uniforms be
worn to prevent contamination or soiling of street clothes.
3. Gloves should be worn if the skin on the hands is broken or if a rash
is present. Alternatives to powdered latex gloves should be
available.
4. Protective eyewear should be worn for conduct of procedures in
which splashes of microorganisms or other hazardous materials is
anticipated.
Biosafety Level 1 (BSL-1)
Laboratory Facilities (Secondary Barriers)
1. Laboratories should have doors for access
control.
 2. Each laboratory contains a sink for hand washing.
 3. The laboratory is designed so that it can be easily
cleaned. Carpets and rugs in laboratories are not
appropriate.

Biosafety Level 1 (BSL-1)
Laboratory Facilities (Secondary Barriers)….



4. Bench tops are impervious to water and are resistant to
moderate heat and the organic solvents, acids, alkalis, and
chemicals used to decontaminate the work surface and
equipment.
5. Laboratory furniture is capable of supporting anticipated
loading and uses. Spaces between benches, cabinets,and
equipment are accessible for cleaning.
6. If the laboratory has windows that open to the exterior, they
are fitted with fly screens.
Biosafety Level 2 (BSL-2)
…. For work involving agents of moderate
potential hazard to personnel and the
environment……
 Standard
Practices apply
Biosafety Level 2 (BSL-2)…
 Special
Practices
1. Access limited
2. Special requirements for entry
3. Warning signs
4. Immunizations/Tests for personnel
5. Baseline serum samples
6. Biosafety manual
7. Training of lab and support personnel
Biosafety Level 2 (BSL-2)…
 8.
Sharps-syringe needles, slides, pipets, capillary
tubes, scalpels, razor blades
 9. Leakproof containers for all potentially
infectious waste
 10. Decontamination of Equipment and work
surfaces
 11. Reporting requirements
 12. Animals
Biosafety Level 2 (BSL-2)…
Safety Equipment-Primary Barriers
 1. Class II biosafety cabinets (BSL), personal protective
equipment, other containment whenever:

a. Infectious aerosols or splashes from:
centrifugation
opening containers
grinding
intranasal inoculation
blending
harvesting tissues
shaking
sonication
Biosafety Level 2 (BSL-2)…
 Safety
Equipment-Primary Barriers…
1… b. high concentrations or large volumes of infectious
agents are used
2. Face protection, when IM used outside BSL
3. Coats, gowns, smocks, overalls
4. Gloves req’d for animals, infected mat’l, contaminated
surfaces & equipment
Biosafety Level 3 (BSL-3)
 “..agents
which may cause serious or potentially
lethal disease as a result of exposure by
inhalation..”


Personnel must have specific training for handling of such agents.
All procedures must be performed in BSCs or other containment
devices.
…Biosafety Level 3 (BSL-3)…
 Special
Practices—like Level 2 but with further
restrictions..
 Baseline serum samples collected from all lab
workers.
 Workers must demonstrate proficiency.
 No open vessels outside of physical containment.
Biosafety Level 3 (BSL-3)
 Safety
Equipment-Primary Barriers
 1. BSC for manipulation of infected materials.
 2. PPE-mask, gloves, respirator, face shield.
Physical containment-caging for animals, sealed
centrifuge rotors.
 3. Protective clothing not allowed out of the lab.
Changing rooms.
Biosafety Level 4 (BSL-4)
 “..dangerous
and exotic agents which carry a high
risk of aerosol transmitted infections and lifethreatening disease..”
 1.
Specialized training for all workers.
 2. All activities confined to class III BSC or class
II BSC used with 1 piece positive pressure suit that
includes life support ventilation.
Biosafety Level 4 (BSL-4)
3. Lab is physically separated from access corridors.
 4. Serological surveillance program.
 5. Enter & leave through airlocks (supplies also),
employees must shower before leaving.
Otherwise much like Level III.

265 page booklet from U.S. Dept of HHS
http://www.cdc.gov/od/ohs/biosfty/bmbl4/bmbl4toc.htm