Transcript Biosafety - UniMAP Portal

ERT 322
SAFETY AND LOSS PREVENTION
BIOSAFETY AND BIOHAZARD SAFETY
Overview
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Biohazard
Biosafety rules & regulations
Risk Assessment
Decontamination
Protection
Biohazard
• A biological hazard or biohazard is an organism,
or substance derived from an organism, that
poses a threat to (primarily) human health.
• This can include medical waste or samples of a
microorganism, virus or toxin (from a biological
source) that can impact human health.
Four Levels of Biosafety
• BSL 1: Material not known to consistently cause
disease in healthy adults.
• BSL 2: Associated with human disease. Hazard is
from percutaneous injury, ingestion, or mucous
membrane exposure.
• BSL 3: Indigenous or exotic agents with potential for
aerosol transmission; disease may have serious or
lethal consequences.
• BSL 4: Dangerous/exotic agents which pose a high
risk of life-threatening disease, aerosol-transmitted
lab infections or related agents with unknown risk of
transmission.
Biosafety Level 1
• agents not known to cause disease in healthy
adult humans
• minimal potential hazard to laboratory personnel
and the environment.
• For microbes example, Escherichia coli, Bacillus
subtilis, Naegleria gruberi.
• Work is generally conducted on open bench tops
using standard microbiological practices
• all materials used for cell and/or bacteria cultures
are decontaminated via autoclave.
Biosafety Level 2
• moderate potential hazard to personnel and the
environment.
• For microbes example, Hepatitis B virus,
Influenza A, Measles virus, dengue fever,
Salmonella.
• certain procedures in which infectious aerosols
or splashes may be created are conducted in
biological safety cabinets or other physical
containment equipment.
Biosafety Level 3
• infectious agents which may cause serious or
potentially lethal disease as a result of exposure
by the inhalation route.
• Exposure potential to pathogens spread by
aerosol.
• Infection serious, possibly lethal
• For microbes example, Coxiella burnetii,
Monkeypox virus, SARS, antrax.
• All procedures involving the manipulation of
infectious materials are conducted within
biological safety cabinets
Biosafety Level 4
• Suitable for work with dangerous and exotic
agents that pose a high individual risk of
aerosol- transmitted laboratory infections and
life-threatening disease.
• Exposure potential to pathogens spread by
aerosol or with unknown risk of transmission.
• Infection possibly lethal.
• For microbes example, Ebola Zaire, Marburg
virus
• When dealing with biological hazards at this
level the use of a Hazmat suit and a selfcontained oxygen supply is mandatory.
Rules & Regulations
• OSHA Bloodborne Pathogens
http://www.osha.gov/SLTC/bloodbornepathogens/index.html
• CDC Select Agents
http://www.cdc.gov/od/ohs/lrsat.htm
• NIH Guidelines for Research Involving Recombinant
DNA Molecules
http://www4.od.nih.gov/oba/rac/guidelines/guidelines.html
• DOT/CDC Shipping
http://www.cdc.gov/od/ohs/biosfty/shipregs.htm
• CDC Import Permits
http://www.cdc.gov/od/ohs/biosfty/imprtper.htm
• USDA/APHIS Permits
http://www.aphis.usda.gov/vs/ncie/
Import Permits
• CDC:
- a permit is required to import etiologic agents
of human disease and any materials,
including live animals or insects, that may
contain them.
- Unsterilized specimens of human and animal
tissues (such as blood, body discharges,
fluids, excretions or similar material)
containing an infectious or etiologic agent
require a permit in order to be imported.
Import Permits
• APHIS: a USDA veterinary permit is needed
for materials derived from animals or
exposed to animal-source materials.
Risk Assessment
Risk of Activity – same agent can have different
containment levels at different stages of protocol:
– Procedures that produce aerosols have higher risk
– Procedures using needles or other sharps have
higher risk
– Handling blood, serum or tissue samples may have
lower risk
– Purified cultures or cell concentrates may have
higher risk
– Larger volumes (10 L) have higher risk
Decontamination
Decontamination
-a process or treatment that renders an
instrument or environmental surface safe to
handle.
- Decontamination procedure can range from
sterilization to simple cleaning with soap and
water.
- Sterilization, disinfection and antisepsis are all
forms of decontamination.
Sterilization is the use of a physical or chemical
procedure to destroy all microbial life, including
highly resistant bacterial endospores.
Antisepsis is the application of a liquid
antimicrobial chemical to skin or living tissue to
inhibit or destroy microorganisms. It includes
swabbing an injection site on a person or animal
and hand washing with germicidal solutions.
Disinfection eliminates virtually all pathogenic
non-sporeforming microorganisms but not
necessarily all microbial forms on inanimate
objects (e.g., work surfaces and equipment).
Effectiveness is influenced by the kinds and
numbers of organisms, the amount of organic
matter, the object to be disinfected and chemical
exposure time, temperature and concentration.
Types of disinfectants – alcohol, aldehydes,
oxidizing agent & phenolics.
Methods of Decontamination
• There are four main categories of physical and
chemical means of decontamination:
(1) Heat;
(2) Liquid disinfection;
(3) Vapors and gases; and
(4) Radiation.
1.
Heat
Wet Heat
Wet heat is the most dependable method of
sterilization. Autoclaving (saturated steam under
pressure of approximately 15 psi (1.02atm) to
achieve a chamber temperature of at least 250°F
(121˚C) for a prescribed time) is the most
convenient method of rapidly achieving
destruction of all forms of microbial life.
The material to be sterilized must come in
contact with steam and heat.
Dry Heat
Dry heat is less efficient than wet heat and
requires longer times and/or higher temperatures
to achieve sterilization.
It is suitable for the destruction of viable
organisms on impermeable non-organic surfaces
such as glass, but it is not reliable in the
presence of shallow layers of organic or
inorganic materials which may act as insulation.
2. Liquid Disinfection
The most practical use of liquid disinfectants is
for surface decontamination and,
as a decontaminate for liquid wastes prior to final
disposal in the sanitary sewer.
Liquid disinfectants are available under a wide
variety of trade names.
 In general, these can be classified as: halogens,
acids, alkalis, heavy metal salts, quaternary
ammonium compounds, phenolic compounds,
aldehydes, ketones, alcohols and amines.
3. Vapors & Gases
Vapors and gases are primarily used to
decontaminate :
biological safety cabinets and associated
systems;
bulky or stationary equipment not suited to
liquid disinfectants;
instruments or optics which might be
damaged by other decontamination methods;
and rooms, buildings and associated airhandling systems.
Agents included in this category are:
- glutaraldehyde and formaldehyde vapor,
- ethylene oxide gas,
- peracetic acid
- hydrogen peroxide vapor.
When used in closed systems and under
controlled conditions of temperature and
humidity, excellent disinfection can be obtained.
4. Radiation
• Although ionizing radiation will destroy
microorganisms, it is not a practical tool for
laboratory use.
• Nonionizing radiation in the form of ultraviolet
radiation (UV) is used for inactivating viruses,
bacteria and fungi.
• It will destroy airborne microorganisms and
inactivate micro-organisms on exposed surfaces
or in the presence of products of unstable
composition that cannot be treated by
conventional means.
• UV can cause burns to the eyes and skin of
people exposed for even a short period of time.
Therefore, proper shielding should be maintained
when it is in use.
Protection: Primary Containment
• Lab practices – standard lab practice,
- limited access,
- biohazard warning sign,
- sharps/needle precautions,
- SOPs for decontamination, waste,
medicals.
• Safety equipment – biosafety cabinets (BSC),
sharps containers, sealed rotors.
• Personal protective equipment (PPE) –
lab coat, gloves, goggles.
Aerosol Precautions
• Use BSC for all procedures that may generate
aerosols.
• Use centrifuges with biosafety covers.
• Do not use a syringe for mixing infectious fluids.
• Cultures, tissues, specimens of body fluids, etc., are
placed in a container with a cover that prevents
leakage during collection, handling, processing,
storage, transport or shipping.
Human Blood, Tissue and Fluid
Occupational Exposure to Bloodborne Pathogens
Occupational Safety & Health Administration (OSHA) 29 CFR 1910.1030
• Use BSL 2 work practices and procedures.
• Everyone needs to be offered the Hepatitis B
vaccine.
• Develop specific exposure plan SOPs.
• Specific training is required.
• Review needle/syringe use and replace with “safe”
devices.
• Exposure incidents must be followed up.
Waste Disposal
• “Red bag” or “Regulated Medical Waste”:
– All mammalian cells or anything that came in
contact with mammalian cells
– All BSL 2 material or anything that came in
contact with BSL 2 material
– All needles/syringes regardless of use
Environmental Safety & Health
Overview: Who has to protect
Exposure Response Plan
• To protect employees from exposure to the
pathogenic microorganism.
• describe ways to eliminate or minimize the danger
of exposure to human blood or other potentially
infectious materials.
• Must be specific to the department
• Update yearly
• Accessible to workers
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