Chapter 4,The containment laboratory –
Biosafety Level 3
The containment laboratory – Biosafety Level
3 is designed and provided for work with Risk
Group 3 microorganisms and with large
volumes or high concentrations of Risk Group
2 microorganisms that pose an increased risk
of aerosol spread,Biosafety Level 3
containment requires the strengthening of the
operational and safety programmes over and
above those for basic laboratories – Biosafety
Levels 1 and 2.
The guidelines given in this chapter are
presented in the form of additions to those
for basic laboratories – Biosafety Levels 1
and 2,which must therefore be applied
before those specific for the containment
laboratory – Biosafety Level 3,The major
additionsand changes are in:
1,Code of practice
2,Laboratory design and facilities
3,Health and medical surveillance,Laboratories
in this category should be registered or listed with
the national or other appropriate health
authorities.
The code of practice for basic laboratories
– Biosafety Levels 1 and 2 applies except
where modified as follows.
1,The international biohazard warning
symbol and sign displayed on laboratory
access doors must identify the biosafety
level and the name of the laboratory
supervisor who controls access,and
indicate any special conditions for entry
into the area,e.g,immunization.
2,Laboratory protective clothing must be of the
type with solid-front or wrap-around gowns,scrub
刷洗 suits,coveralls,head covering and,where
appropriate,shoe covers or dedicated shoes,Front-
buttoned standard laboratory coats are unsuitable,
as are sleeves that do not fully cover the forearms,
Laboratory protective clothing must not be worn
outside the laboratory,and it must be
decontaminated before it is laundered洗烫,The
removal of street clothing and change into
dedicated laboratory clothing may be warranted
when working with certain agents (e.g,agricultural
orzoonotic agents).
3,Open manipulations of all potentially infectious
material must be conducted within a biological
safety cabinet or other primary containment device
(see also Chapter 10).
4,Respiratory protective equipment may be
necessary for some laboratory proceduresor
working with animals infected with certain
pathogens (see Chapter 11).
Laboratory design and facilities
The laboratory design and facilities for
basic laboratories – Biosafety Levels 1 and
2 apply except where modified as follows:
1,The laboratory must be separated from the areas
that are open to unrestricted traffic flow within the
building,Additional separation may be achieved by
placing the laboratory at the blind end of a
corridor,or constructing a partition and door or
access through an anteroom (e.g,a double-door
entry or basic laboratory –Biosafety Level 2),
describing a specific area designed to maintain the
pressure differential between the laboratory and its
adjacent space,The anteroom should have facilities
for separating clean and dirty clothing and a
shower may also be necessary.
2,Anteroom doors may be self-closing and
interlocking so that only one door is open at a
time,A break-through panel may be provided
for emergency exit use.
3,Surfaces of walls,floors and ceilings should be
water-resistant and easy to clean,Openings
through these surfaces (e.g,for service pipes)
should be sealed to facilitate decontamination of
the room(s).
4,The laboratory room must be sealable for
decontamination,Air-ducting systems must be
constructed to permit gaseous decontamination.
5,Windows must be closed,sealed and break-
resistant.
6,A hand-washing station with hands-free
controls should be provided near each exit door.
7,There must be a controlled ventilation system
that maintains a directional airflow into the
laboratory room,A visual monitoring device
with or without alarm(s) should be installed so
that staff can at all times ensure that proper
directional airflow into the laboratory room is
maintained.
8,The building ventilation system must be so
constructed that air from the containment
laboratory – Biosafety Level 3 is not recirculated
to other areas within the building,Air may be
high-efficiency particulate air (HEPA) filtered,
reconditioned and recirculated within that
laboratory,
When exhaust air from the laboratory (other than
from biological safety cabinets) is discharged to the
outside of the building,it must be dispersed away
from occupied buildings and air intakes,
Depending on the agents in use,this air may be
discharged through HEPA filters,A heating,
ventilation and air-conditioning (HVAC) control
system may be installed to prevent sustained
positive pressurization of the laboratory,
Consideration should be given to the installation of
audible or clearly visible alarms to notify personnel
of HVAC system failure.
9,All HEPA filters must be installed in a
manner that permits gaseous decontamination
and testing.
10,Biological safety cabinets should be sited
away from walking areas and out of cross-
currents from doors and ventilation systems.
(HEPA =high-efficiency particulate air )
11,The exhaust air from Class I or Class II
biological safety cabinets (see Chapter10),which
will have been passed through HEPA filters,
must be discharged in such away as to avoid
interference with the air balance of the cabinet or
the building exhaust system.
12.An autoclave for the decontamination of
contaminated waste material should be available
in the containment laboratory,If infectious waste
has to be removed from the containment
laboratory for decontamination and disposal,it
must be transported in sealed,unbreakable and
leakproof containers according to national or
international regulations,as appropriate.
13,Backflow-precaution devices must be fitted
to the water supply,Vacuum lines should be
protected with liquid disinfectant traps and
HEPA filters,or their equivalent.Alternative
vacuum pumps should also be properly
protected with traps and filters.
14,The containment laboratory – Biosafety
Level 3 facility design and operational
procedures should be documented,
An example of laboratory design for Biosafety
Level 3,
Laboratory equipment
The principles for the selection of laboratory
equipment,including biological safety cabinets
(see Chapter10) are the same as for the basic
laboratory – Biosafety Level 2.However,at
Biosafety Level 3,manipulation of all
potentially infectious material must be
conducted within a biological safety cabinet or
other primary containment device.
Consideration should be given to equipment such
as centrifuges,which will need additional
containment accessories,for example,safety
buckets or containment rotors.Some centrifuges
and other equipment,such as cell-sorting
instruments for use with infected cells,may need
additional local exhaust ventilation with HEPA
filtration for efficient containment.
Health and medical surveillance
The objectives of health and medical
surveillance programmes for basic
laboratories –Biosafety Levels 1 and 2 also
apply to containment laboratories –
Biosafety Level 3,except where modified as
follows:
1,Medical examination of all laboratory
personnel who work in containment
laboratories – Biosafety Level 3 is mandatory强制性的,This should include recording of a
detailed medical history and an occupationally-
targeted physical examination.
2,After a satisfactory clinical assessment,the
examinee may be provided with a medical contact
card stating that he or she is employed in a facility
with a containment laboratory – Biosafety Level 3,
This card should include a picture of the card
holder,be wallet-sized,and always be carried by
the holder,The name(s) of the contact persons to
be entered will need to be agreed locally but might
include the laboratory director,medical adviser
and/or biosafety officer.
正面背面
Chapter 5,The maximum containment
laboratory – Biosafety Level 4
The maximum containment laboratory – Biosafety
Level 4 is designed for work with Risk Group 4
microorganisms,Before such a laboratory is
constructed and put into operation,intensive
consultations should be held with institutions that
have had experience of operating a similar facility,
Operational maximum containment laboratories
– Biosafety Level 4 should be under the control of
national or other appropriate health authorities,
The following information is intended only as
introductory material,Entities working to pursue
development of a Biosafety Level 4laboratory
should contact the WHO Biosafety programme
for additional information.
Code of practice
The code of practice for Biosafety Level 3 applies
except where modified as follows:
1,The two-person rule should apply,whereby no
individual ever works alone,This is particularly
important if working in a Biosafety Level 4 suit
facility.
2,A complete change of clothing and shoes is
required prior to entering and upon exiting the
laboratory.
3,Personnel must be trained in emergency
extraction procedures in the event of personnel
injury or illness.4,A method of communication for
routine and emergency contacts must be
established between personnel working within the
maximum containment laboratory – Biosafety
Level 4 and support personnel outside the
laboratory.Laboratory design and facilities
The features of a containment laboratory –
Biosafety Level 3 also apply to a maximum
containment laboratory – Biosafety Level 4
with the addition of the following:
(1) Primary containment,
An efficient primary containment system
must be in place,consisting of one or a
combination of the following:
(a) — Class III cabinet laboratory,
Passage through a minimum of two doors prior to
entering the rooms containing the Class III
biological safety cabinet(s) (cabinet room) is
required,
In this laboratory configuration the Class III
biological safety cabinet provides the primary
containment,
A personnel shower with inner and outer
changing rooms is necessary,
Supplies and materials that are not brought into
the cabinet room through the changing area are
introduced through a double-door autoclave or
fumigation熏蒸 chamber,
Once the outer door is securely closed,staff
inside the laboratory can open the inner door to
retrieve the materials,
The doors of the autoclave or fumigation
chamber are interlocked in such a way that the
outer door cannot open unless the autoclave has
been operated through a sterilization cycle or the
fumigation chamber has been decontaminated.
(b) — Suit laboratory,A protective suit laboratory
with self-contained breathing apparatus differs
significantly in design and facility requirements
from a Biosafety Level 4 laboratory with Class III
biological safety cabinets,
The rooms in the protective suit laboratory are
arranged so as to direct personnel through the
changing and decontamination areas prior to
entering areas where infectious materials are
manipulated.
A suit decontamination shower must be
provided and used by personnel leaving the
containment laboratory area,A separate
personnel shower with inner and outer changing
rooms is also provided,Personnel who enter the
suit area are required to don a one-piece,
positively pressurized,
HEPA-filtered,supplied-air suit,Air to the suit
must be provided by a system that has a 100%
redundant capability with an independent
source of air,for use in the event of an
emergency,
Entry into the suit laboratory is through an
airlock fitted with airtight doors,An
appropriate warning system for personnel
working in the suit laboratory must be provided
for use in the event of mechanical system or air
failure.
(2) Controlled access,The maximum containment
laboratory – Biosafety Level 4 must be located in
a separate building or in a clearly delineated划定的
zone within a secure building,
Entry and exit of personnel and supplies must be
through an airlock or pass-through system,On
entering,personnel must put on a complete
change of clothing; before leaving,they should
shower before putting on their street clothing.
(3) Controlled air system,
Negative pressure must be maintained in the
facility,Both supply and exhaust air must be
HEPA-filtered,There are significant differences in
the ventilating systems of the Class III cabinet
laboratory and suit laboratory:
— Class III cabinet laboratory,
The supply air to the Class III biological safety
cabinet(s) may be drawn from within the room
through a HEPA filter mounted on the cabinet or
supplied directly through the supply air system,
Exhaust air from the Class III biological safety
cabinet must pass through two HEPA filters prior
to release outdoors,
The cabinet must be operated at negative pressure
to the surrounding laboratory at all times.
A dedicated non-recirculating ventilating system
for the cabinet laboratory is required,
— Suit laboratory,Dedicated room air supply
and exhaust systems are required,The supply
and exhaust components of the ventilating system
are balanced to provide directional airflow
within the suit area from the area of least hazard
to the area(s) of greatest potential hazard,
Redundant exhaust fans are required to ensure
that the facility remains under negative pressure at
all times,The differential pressures within the suit
laboratory and between the suit laboratory and
adjacent areas must be monitored.
Airflow in the supply and exhaust components of
the ventilating system must be monitored,and an
appropriate system of controls must be used to
prevent pressurization of the suit laboratory,
HEPA-filtered supply air must be provided to the
suit area,decontamination shower and
decontamination airlocks or chambers.
Exhaust air from the suit laboratory must be
passed through a series of two HEPA filters prior
to release outdoors,Alternatively,after double
HEPA filtration,exhaust air may be recirculated,
but only within the suit laboratory,
Under no circumstances shall the exhaust air from
the Biosafety Level 4 suit laboratory be
recirculated to other areas,Extreme caution must
be exercised if recirculation of air within the suit
laboratory is elected,
Consideration must be given to the types of
research conducted,equipment,chemicals and
other materials used in the suit laboratory,as well
as animal species that may be involved in the
research.
All HEPA filters need to be tested and certified
annually,The HEPA filter housings are designed to
allow for in situ decontamination of the filter prior
to removal,Alternatively,the filter can be removed
in a sealed,gas-tight primary container for
subsequent decontamination and/or destruction by
incineration.
(4) Decontamination of effluents,All effluents from
the suit area,decontamination chamber,
decontamination shower,or Class III biological
safety cabinet must be decontaminated before final
discharge,
Heat treatment is the preferred method,Effluents
may also require correction to a neutral pH prior
to discharge.
Water from the personnel shower and toilet may
be discharged directly to the sanitary sewer
without treatment.
(5) Sterilization of waste and materials,A double-
door,pass-through autoclave must be available in
the laboratory area,Other methods of
decontamination must be available for equipment
and items that cannot withstand steam
sterilization.
(6.)Airlock entry ports for specimens,materials
and animals must be provided,
(7,)Emergency power and dedicated power supply
line(s) must be provided,
(8.) Containment drain(s) must be installed,
Because of the great complexity of the engineering,
design and construction of Biosafety Level 4
facilities,in either cabinet or suit configuration,
schematic representations of such facilities have
not been included,
Because of the great complexity of the work in the
Biosafety Level 4 laboratory,a separate detailed
work manual should be developed and tested in
training exercises.
In addition,an emergency programme must be
devised,In the preparation of this programme,
active cooperation with national and local health
authorities should be established,Other emergency
services,e.g,fire,police and designated receiving
hospitals,should also be involved.
Biosafety Level 3
The containment laboratory – Biosafety Level
3 is designed and provided for work with Risk
Group 3 microorganisms and with large
volumes or high concentrations of Risk Group
2 microorganisms that pose an increased risk
of aerosol spread,Biosafety Level 3
containment requires the strengthening of the
operational and safety programmes over and
above those for basic laboratories – Biosafety
Levels 1 and 2.
The guidelines given in this chapter are
presented in the form of additions to those
for basic laboratories – Biosafety Levels 1
and 2,which must therefore be applied
before those specific for the containment
laboratory – Biosafety Level 3,The major
additionsand changes are in:
1,Code of practice
2,Laboratory design and facilities
3,Health and medical surveillance,Laboratories
in this category should be registered or listed with
the national or other appropriate health
authorities.
The code of practice for basic laboratories
– Biosafety Levels 1 and 2 applies except
where modified as follows.
1,The international biohazard warning
symbol and sign displayed on laboratory
access doors must identify the biosafety
level and the name of the laboratory
supervisor who controls access,and
indicate any special conditions for entry
into the area,e.g,immunization.
2,Laboratory protective clothing must be of the
type with solid-front or wrap-around gowns,scrub
刷洗 suits,coveralls,head covering and,where
appropriate,shoe covers or dedicated shoes,Front-
buttoned standard laboratory coats are unsuitable,
as are sleeves that do not fully cover the forearms,
Laboratory protective clothing must not be worn
outside the laboratory,and it must be
decontaminated before it is laundered洗烫,The
removal of street clothing and change into
dedicated laboratory clothing may be warranted
when working with certain agents (e.g,agricultural
orzoonotic agents).
3,Open manipulations of all potentially infectious
material must be conducted within a biological
safety cabinet or other primary containment device
(see also Chapter 10).
4,Respiratory protective equipment may be
necessary for some laboratory proceduresor
working with animals infected with certain
pathogens (see Chapter 11).
Laboratory design and facilities
The laboratory design and facilities for
basic laboratories – Biosafety Levels 1 and
2 apply except where modified as follows:
1,The laboratory must be separated from the areas
that are open to unrestricted traffic flow within the
building,Additional separation may be achieved by
placing the laboratory at the blind end of a
corridor,or constructing a partition and door or
access through an anteroom (e.g,a double-door
entry or basic laboratory –Biosafety Level 2),
describing a specific area designed to maintain the
pressure differential between the laboratory and its
adjacent space,The anteroom should have facilities
for separating clean and dirty clothing and a
shower may also be necessary.
2,Anteroom doors may be self-closing and
interlocking so that only one door is open at a
time,A break-through panel may be provided
for emergency exit use.
3,Surfaces of walls,floors and ceilings should be
water-resistant and easy to clean,Openings
through these surfaces (e.g,for service pipes)
should be sealed to facilitate decontamination of
the room(s).
4,The laboratory room must be sealable for
decontamination,Air-ducting systems must be
constructed to permit gaseous decontamination.
5,Windows must be closed,sealed and break-
resistant.
6,A hand-washing station with hands-free
controls should be provided near each exit door.
7,There must be a controlled ventilation system
that maintains a directional airflow into the
laboratory room,A visual monitoring device
with or without alarm(s) should be installed so
that staff can at all times ensure that proper
directional airflow into the laboratory room is
maintained.
8,The building ventilation system must be so
constructed that air from the containment
laboratory – Biosafety Level 3 is not recirculated
to other areas within the building,Air may be
high-efficiency particulate air (HEPA) filtered,
reconditioned and recirculated within that
laboratory,
When exhaust air from the laboratory (other than
from biological safety cabinets) is discharged to the
outside of the building,it must be dispersed away
from occupied buildings and air intakes,
Depending on the agents in use,this air may be
discharged through HEPA filters,A heating,
ventilation and air-conditioning (HVAC) control
system may be installed to prevent sustained
positive pressurization of the laboratory,
Consideration should be given to the installation of
audible or clearly visible alarms to notify personnel
of HVAC system failure.
9,All HEPA filters must be installed in a
manner that permits gaseous decontamination
and testing.
10,Biological safety cabinets should be sited
away from walking areas and out of cross-
currents from doors and ventilation systems.
(HEPA =high-efficiency particulate air )
11,The exhaust air from Class I or Class II
biological safety cabinets (see Chapter10),which
will have been passed through HEPA filters,
must be discharged in such away as to avoid
interference with the air balance of the cabinet or
the building exhaust system.
12.An autoclave for the decontamination of
contaminated waste material should be available
in the containment laboratory,If infectious waste
has to be removed from the containment
laboratory for decontamination and disposal,it
must be transported in sealed,unbreakable and
leakproof containers according to national or
international regulations,as appropriate.
13,Backflow-precaution devices must be fitted
to the water supply,Vacuum lines should be
protected with liquid disinfectant traps and
HEPA filters,or their equivalent.Alternative
vacuum pumps should also be properly
protected with traps and filters.
14,The containment laboratory – Biosafety
Level 3 facility design and operational
procedures should be documented,
An example of laboratory design for Biosafety
Level 3,
Laboratory equipment
The principles for the selection of laboratory
equipment,including biological safety cabinets
(see Chapter10) are the same as for the basic
laboratory – Biosafety Level 2.However,at
Biosafety Level 3,manipulation of all
potentially infectious material must be
conducted within a biological safety cabinet or
other primary containment device.
Consideration should be given to equipment such
as centrifuges,which will need additional
containment accessories,for example,safety
buckets or containment rotors.Some centrifuges
and other equipment,such as cell-sorting
instruments for use with infected cells,may need
additional local exhaust ventilation with HEPA
filtration for efficient containment.
Health and medical surveillance
The objectives of health and medical
surveillance programmes for basic
laboratories –Biosafety Levels 1 and 2 also
apply to containment laboratories –
Biosafety Level 3,except where modified as
follows:
1,Medical examination of all laboratory
personnel who work in containment
laboratories – Biosafety Level 3 is mandatory强制性的,This should include recording of a
detailed medical history and an occupationally-
targeted physical examination.
2,After a satisfactory clinical assessment,the
examinee may be provided with a medical contact
card stating that he or she is employed in a facility
with a containment laboratory – Biosafety Level 3,
This card should include a picture of the card
holder,be wallet-sized,and always be carried by
the holder,The name(s) of the contact persons to
be entered will need to be agreed locally but might
include the laboratory director,medical adviser
and/or biosafety officer.
正面背面
Chapter 5,The maximum containment
laboratory – Biosafety Level 4
The maximum containment laboratory – Biosafety
Level 4 is designed for work with Risk Group 4
microorganisms,Before such a laboratory is
constructed and put into operation,intensive
consultations should be held with institutions that
have had experience of operating a similar facility,
Operational maximum containment laboratories
– Biosafety Level 4 should be under the control of
national or other appropriate health authorities,
The following information is intended only as
introductory material,Entities working to pursue
development of a Biosafety Level 4laboratory
should contact the WHO Biosafety programme
for additional information.
Code of practice
The code of practice for Biosafety Level 3 applies
except where modified as follows:
1,The two-person rule should apply,whereby no
individual ever works alone,This is particularly
important if working in a Biosafety Level 4 suit
facility.
2,A complete change of clothing and shoes is
required prior to entering and upon exiting the
laboratory.
3,Personnel must be trained in emergency
extraction procedures in the event of personnel
injury or illness.4,A method of communication for
routine and emergency contacts must be
established between personnel working within the
maximum containment laboratory – Biosafety
Level 4 and support personnel outside the
laboratory.Laboratory design and facilities
The features of a containment laboratory –
Biosafety Level 3 also apply to a maximum
containment laboratory – Biosafety Level 4
with the addition of the following:
(1) Primary containment,
An efficient primary containment system
must be in place,consisting of one or a
combination of the following:
(a) — Class III cabinet laboratory,
Passage through a minimum of two doors prior to
entering the rooms containing the Class III
biological safety cabinet(s) (cabinet room) is
required,
In this laboratory configuration the Class III
biological safety cabinet provides the primary
containment,
A personnel shower with inner and outer
changing rooms is necessary,
Supplies and materials that are not brought into
the cabinet room through the changing area are
introduced through a double-door autoclave or
fumigation熏蒸 chamber,
Once the outer door is securely closed,staff
inside the laboratory can open the inner door to
retrieve the materials,
The doors of the autoclave or fumigation
chamber are interlocked in such a way that the
outer door cannot open unless the autoclave has
been operated through a sterilization cycle or the
fumigation chamber has been decontaminated.
(b) — Suit laboratory,A protective suit laboratory
with self-contained breathing apparatus differs
significantly in design and facility requirements
from a Biosafety Level 4 laboratory with Class III
biological safety cabinets,
The rooms in the protective suit laboratory are
arranged so as to direct personnel through the
changing and decontamination areas prior to
entering areas where infectious materials are
manipulated.
A suit decontamination shower must be
provided and used by personnel leaving the
containment laboratory area,A separate
personnel shower with inner and outer changing
rooms is also provided,Personnel who enter the
suit area are required to don a one-piece,
positively pressurized,
HEPA-filtered,supplied-air suit,Air to the suit
must be provided by a system that has a 100%
redundant capability with an independent
source of air,for use in the event of an
emergency,
Entry into the suit laboratory is through an
airlock fitted with airtight doors,An
appropriate warning system for personnel
working in the suit laboratory must be provided
for use in the event of mechanical system or air
failure.
(2) Controlled access,The maximum containment
laboratory – Biosafety Level 4 must be located in
a separate building or in a clearly delineated划定的
zone within a secure building,
Entry and exit of personnel and supplies must be
through an airlock or pass-through system,On
entering,personnel must put on a complete
change of clothing; before leaving,they should
shower before putting on their street clothing.
(3) Controlled air system,
Negative pressure must be maintained in the
facility,Both supply and exhaust air must be
HEPA-filtered,There are significant differences in
the ventilating systems of the Class III cabinet
laboratory and suit laboratory:
— Class III cabinet laboratory,
The supply air to the Class III biological safety
cabinet(s) may be drawn from within the room
through a HEPA filter mounted on the cabinet or
supplied directly through the supply air system,
Exhaust air from the Class III biological safety
cabinet must pass through two HEPA filters prior
to release outdoors,
The cabinet must be operated at negative pressure
to the surrounding laboratory at all times.
A dedicated non-recirculating ventilating system
for the cabinet laboratory is required,
— Suit laboratory,Dedicated room air supply
and exhaust systems are required,The supply
and exhaust components of the ventilating system
are balanced to provide directional airflow
within the suit area from the area of least hazard
to the area(s) of greatest potential hazard,
Redundant exhaust fans are required to ensure
that the facility remains under negative pressure at
all times,The differential pressures within the suit
laboratory and between the suit laboratory and
adjacent areas must be monitored.
Airflow in the supply and exhaust components of
the ventilating system must be monitored,and an
appropriate system of controls must be used to
prevent pressurization of the suit laboratory,
HEPA-filtered supply air must be provided to the
suit area,decontamination shower and
decontamination airlocks or chambers.
Exhaust air from the suit laboratory must be
passed through a series of two HEPA filters prior
to release outdoors,Alternatively,after double
HEPA filtration,exhaust air may be recirculated,
but only within the suit laboratory,
Under no circumstances shall the exhaust air from
the Biosafety Level 4 suit laboratory be
recirculated to other areas,Extreme caution must
be exercised if recirculation of air within the suit
laboratory is elected,
Consideration must be given to the types of
research conducted,equipment,chemicals and
other materials used in the suit laboratory,as well
as animal species that may be involved in the
research.
All HEPA filters need to be tested and certified
annually,The HEPA filter housings are designed to
allow for in situ decontamination of the filter prior
to removal,Alternatively,the filter can be removed
in a sealed,gas-tight primary container for
subsequent decontamination and/or destruction by
incineration.
(4) Decontamination of effluents,All effluents from
the suit area,decontamination chamber,
decontamination shower,or Class III biological
safety cabinet must be decontaminated before final
discharge,
Heat treatment is the preferred method,Effluents
may also require correction to a neutral pH prior
to discharge.
Water from the personnel shower and toilet may
be discharged directly to the sanitary sewer
without treatment.
(5) Sterilization of waste and materials,A double-
door,pass-through autoclave must be available in
the laboratory area,Other methods of
decontamination must be available for equipment
and items that cannot withstand steam
sterilization.
(6.)Airlock entry ports for specimens,materials
and animals must be provided,
(7,)Emergency power and dedicated power supply
line(s) must be provided,
(8.) Containment drain(s) must be installed,
Because of the great complexity of the engineering,
design and construction of Biosafety Level 4
facilities,in either cabinet or suit configuration,
schematic representations of such facilities have
not been included,
Because of the great complexity of the work in the
Biosafety Level 4 laboratory,a separate detailed
work manual should be developed and tested in
training exercises.
In addition,an emergency programme must be
devised,In the preparation of this programme,
active cooperation with national and local health
authorities should be established,Other emergency
services,e.g,fire,police and designated receiving
hospitals,should also be involved.
