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4: Requirements |
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5.1
General
A
summary of the main requirements relating to biological safety
is given below. Each institute, centre, department or group
carrying out biological work should make arrangements to:
-
set up or contact an appropriate committee, group or person
to advise on biological safety measures to be taken in accordance
with institutional guidance;
- appoint
a Biological Safety Officer - and deputy, if appropriate;
- assess
all work involving pathogens and, in the case of genetic modification,
prepare a written assessment in accordance with the approved
method;
- ensure
that the laboratory facilities conform to the required containment
levels;
- ensure
the correct maintenance and testing of microbiological safety
cabinets;
- notify
the Safety Officer in advance of the start of work involving
Group 3 or 4 pathogens;
- notify
the Safety Officer before starting work involving genetic
modification, certain uses of genetically modified organisms,
the intentional release of genetically modified organisms,
and any genetic modification work requiring containment level
3 or 4;
- report
micro-organisms used or intended to be used in the department;
- report
proposals to use microbiological safety cabinets that are
vented to the outside air;
- ensure
that adequate training, instruction and supervision are provided;
- report,
on request, details of genetic modification work requiring
containment levels 1 and 2.
Work undertaken
may be assigned to different hazard groups with various containment
requirements and attendant risk assessment. All work must be
carried out in a facility with the correct containment level
or higher. It is the responsibility of the supervisor or host
institution to ensure that this is done. Codes of practice relating
to the containment levels should be available. Alternatively,
the researcher may refer to various national or international
guidelines, such as University of Oxford Guideline S4/92.10
5.2
Biosafety
Four
biosafety levels are defined and the required laboratory facilities
must be available before the project is initiated. The selection
of any given biosafety level depends on the risk assessment
of the project.
5.2.1
Biosafety level 1 (BL1)
The
standard laboratory practices, safety equipment and facilities
appropriate for secondary educational and undergraduate training
and teaching are required. Research involving defined and characterised
strains of viable infectious agents not known to cause disease
in healthy adults or to colonise humans or animals falls into
this category.
Requirements:
A basic laboratory without safety equipment is adequate. Primary
containment must be practised by adhering to standard laboratory
practices during open bench operations.
5.2.2
Biosafety level 2 (BL2)
Risk
is associated with exposure by ingestion, inoculation or mucous
membrane contamination, but not normally by exposure to aerosols.
The standard
microbiological practices plus the following are necessary:
the wearing of protective gloves and coats when conducting procedures
with infective agents; decontamination of all waste; the erection
of biohazard signs; control of access. These precautions are
applicable in clinical, diagnostic, teaching and other facilities
when working with the broad spectrum of indigenous, moderate-risk
agents present in the community and associated with human disease
of varying severity. Activities with low aerosol potential using
such agents may be conducted on the open bench, using good microbiological
techniques.
Requirements:
A containment laboratory with partial containment equipment
(Class I or II biological safety cabinets) must be used to isolate
mechanical and manipulative procedures that produce readily
detectable aerosols. Sealed rotor centrifuges and an autoclave
are required.
BL2 applies
to an organism that may cause human disease and be a hazard
to laboratory workers, but is unlikely to spread to the community.
Laboratory exposure rarely produces infection and effective
prophylaxis or effective treatment is usually available.
5.2.3
Biosafety level 3 (BL3)
Aerosol-borne
disease is a primary concern at this level, which also implies
high risk at low dosage of life-threatening disease.
In addition
to BL2 practices, the following are necessary: special laboratory
clothing and controlled access. These precautions are appropriate
in clinical, diagnostic, teaching, research or production facilities
when working with indigenous or exotic agents which may readily
cause potentially fatal infections.
Requirements:
A containment laboratory with partial or total containment equipment
(Class I, II or III biological safety cabinets) must be used
to isolate all procedures that may produce aerosols.
This includes
the availability of respiratory protective equipment and air-conditioning;
HEPA filtered exhaust air; controlled access and training of
all users of the facility. Regular monitoring of users is suggested,
and a medical consultant should be available for referral. Standard
operating procedures (SOP) should be adhered to and there should
be ready access to appropriate medical treatment - for example,
access to anti-retrovirals in the case of needle-stick injuries
when working with HIV-containing material.
BL3 applies
to organisms that may cause severe human disease and that present
a serious hazard to laboratory workers. It may present a risk
of spreading to the community, but there is usually effective
prophylaxis or treatment available.
5.2.4
Biosafety level 4 (BL4)
In
this case, agents are readily transmissible, they produce very
serious and often fatal disease and treatment is limited or
unavailable. This category of biocontainment applies to work
on parasites or infectious agents such as exotic or eradicated
agents whose acquisition and maintenance is entirely proscribed
or is authorised only in exceptional circumstances by the authorities
in charge of health, agriculture and the environment. Access
to such a facility should be severely restricted and closely
monitored, and the unit should preferably be structurally independent.
The unit must be sealed and airtight.
In addition
to BL3 practices, the following are necessary: entrance through
a changeroom where street clothing is removed and laboratory
clothing donned; shower on exit; all wastes are decontaminated
on exit from the facility.
Requirements:
A maximum containment laboratory with total containment equipment
(Class III biological safety cabinets) or full-body, air-supplied,
positive-pressure, personnel suits for all procedures and activities.
All effluents, including air, must be decontaminated.
BL4 applies
to an organism that causes severe human disease and is a serious
hazard to laboratory workers. It may present a high risk of
spread to the community and there is usually no effective prophylaxis
or treatment.
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