Transcript No Slide Title

Controls in Biosafety I
EMD545b Lecture #5
Facility Design &
Engineering Controls
Facility Design Overview
• Goals:
– Separation of hazardous work from public
spaces (isolation of lab, prevent accidental
release)
– Controlled airflow
• product protection vs. personnel protection
• combination of both?
• negative pressure, air changes per hour
Facility Design Overview
• Security/Life Safety Elements
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fire rated doors
emergency lighting
Intrusion alarms (motion detectors, etc.)
restricted access (locks, keycard)
lock boxes, locked storage equipment
background checks on personnel
Facility Design Overview
Secondary Barriers
• BSL1 - BSL4 Laboratories
– BSL1 - basic lab
– BSL2 - basic lab + aerosol confinement
• biosafety cabinet
– BSL3 - containment laboratory
• 2 door separation from building occupants
– BSL4 - maximum containment laboratory
• separate building from general research population
Biosafety Level 1 Laboratory
• Door
• Sink
• Easily cleaned work
surfaces
• Impervious bench
tops
• Sturdy furniture
• Windows fitted with
fly screens
BSL2 Laboratory
• BSL1 Lab plus:
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lockable doors
chairs covered with non-fabric material
Biosafety cabinets installed as needed
eyewash available
negative airflow, non-recirculation
recommended
– door closed when work is in progress
– autoclave within facility
Signs and Labels
• Biohazard warning labels on equipment
Biosafety Level 3
“The laboratory has special
engineering and design features.”
CDC/NIH BMBL, 5th Ed. 2007
BL3 Lab Design Elements
• 2 door entry (ante-room, airlock)
• Solid easily cleanable surfaces (floor, walls,
ceiling)
• Coved floors
• Sealed penetrations
• Lighting flush to ceiling
• Hands-free sink near exit door
• Eyewash/shower station
• Pass through autoclave
Wash hands
after removing
PPE at the
hands-free sink
Eye/face wash: understand how to use, flush at
least weekly, and identify closest station outside the
BSL-3 lab (in event of release outside of
containment)
Signs and
Labels
• BL3 Door Sign
– agent name
– entry requirements
– emergency contact(s)
• lab personnel
• safety personnel
• campus emergency
responders
BL3 Lab Design Elements
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Negative airflow (into lab)
Most negative at rear of lab
> 12 air changes per hour
-0.05”H20 pressure diff.
Dedicated exhaust fan
Exhaust/supply interlock
Exhaust velocity >3000 fpm, away from
intakes, people
• Direct exhaust, no recirculation
BL3 Lab Design Elements
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Airflow monitor, gauges
CO2/N2 feed from outside
Keycard, locked access
Doors open inward, self-closing
Access fixtures from outside space
Door sign at entry
Class II BSC
Canopy exhaust over BSC
Means of communication to areas outside lab
BSL-3 Lab Design
Exhaust stack velocity
> 3000 fpm, away
from air intake
Exhaust HEPA filter, in
accessible location for
testing, minimize
contaminated ductwork
Supply Fan - interlocked with
Exhaust Fan, > 50 ft away from
exhaust
-0.05” to -0.1”
H20 pressure
diff. at each
door
BSL-3 Lab Design
Dedicated exhaust
fan, no
recirculation
Exhaust > supply
by 15% or 100
CFM
12 – 15 Air
Changes per
Hour (constant
flow)
Sealed
penetrations
(non-shrink
sealants)
Dedicated
supply fan
preferred
Controlled
airflow into
the lab
Visible
airflow
indicator
at each
entry
BSL-3 Lab Design
Positive seal
dampers on each
side of exhaust
filter
Canopy/thimble
over biosafety
cabinet
Audible &
visual airflow
alarms
Class II
Biosafety
cabinet
Centrifuge with
aerosol
containment
Positive seal
damper on supply
air duct(s)
Pass
through
autoclave
BSL-3 Lab Design
Lighting flush with
ceiling with access
from outside
containment
Vacuum
system
HEPA
filtered
Gases (CO2/N2)
piped into lab from
outside containment
Solid ceiling and
walls
Benches
resistant to
chemicals
used
Monolithic floor
with coved wall
base
Access
to repair
of
equip.
from
outer
area
Emergency backup power for fans
and equipment
BSL-3 Lab Design
Bag-in bag-out filter
housing
Ports pre/post exhaust
filter for HCHO
decon./sampling
Trained
personnel
Supply HEPA as
backflow prevention
BSL-3 AG, Canada
BSL-3
BSL-3 Lab Design
Eye Wash and
Emergency
Shower
Secure
keycard
access
door
Biohazard
door sign
Automatic or
hands-free
sink near exit
Backflow
prevention on
sink
Effluent Sterilization
Tank (BSL-3 AG/BSL-4)
Two
door
entry
from hall
corridor
BSL-3 Lab Design
Consideration of
back-up exhaust fan
Potential for separate
clean and dirty change
anterooms w/
personnel shower
Consideration of
back-up exhaust
HEPA
Fire sprinklers
Phone, fax
– to outside
Locked boxes, locked
equipment (biosecurity)
Motion
detectors,
intrusion
alarms
BSL-3 Lab Design
Ducts under negative
pressure within the
building
Minimize length of
contaminated ductwork
Contaminated ducts labeled
w/biohazard symbol
Sealed
windows if
present
Surface mounted
electrical outlets
Glass break
alarms
Alarms to 24/7
Control Center
Anteroom
or airlock
BSL-3 Lab Design
Ceilings: similar to
walls
Wall finishings: enamel,
epoxy, acrylic latex
Walls:
concrete
block,
cement
board, plastic
Floors: heat seamed
vinyl or poured epoxy
Doors
open
inward,
& selfclosing
Preparation Procedures
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Entry
Procedures
Verify airflow
Enter ante room
Close outer door
Sign log book
Don PPE
Supplies
Enter laboratory
For work in a Biosafety Cabinet
• solid-front or wraparound gown
• gloves (double
gloving)
• face protection (face
shield or mask and
safety glasses)
Use of a HEPA-filtered PAPR for additional
protection during high-risk research procedures
For work outside a Biosafety cabinet
• solid-front or wraparound gown or jump
suit
• gloves (double gloving)
• face protection (face
shield or mask and safety
glasses)
• Respiratory protection if
aerosols are generated
Autoclave located
within BSL-3
Laboratory
All waste from BSL-3
lab must be
autoclaved prior to
disposal
Label autoclaved BSL-3
waste as “Pathological
Waste” for incineration
BL4 Lab - Max Containment
Containment Lab Planning Team
• Project managers, engineers, architects,
electricians, HVAC, controls, safety, researchers,
USERS!
• Formal program document of requirements
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description of all proposed activities
#’s (personnel occupancy)
major equipment requirements
space allocation
general environmental control criteria
facility controls
Containment Lab Planning Team
• Questions:
– Specific single project?
– Future changes, government regulations?
– Flexibility in design?
– Pathogenic microbes used?
– Quarantine areas needed?
– Animals? #’s? Species?
– Treatment of liquid or air effluents?
– Transitional areas needed?
– Finishings, Services (water, vacuum, gas, air, etc.)
– Commissioning/Verification
Communication
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Local/state public health offices
Public affairs office
Biosafety Committee
Citizens (neighbors)
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Toronto debacle
Winnipeg’s “accident”
CDC (in the shadow of Emory University)
The BU BSL4 Lab
Community Design Wish List
• HEPA filtered exhaust air
• Alarms & supply/exhaust interlock
• Emergency back-up power (fan, biosafety
cabinets, freezers)
• Effluent sterilization system
• Pass through autoclave
• Shower
Community Design Wish List
• True airlock
• Separate clean (entry) and dirty (exit)
anterooms
• Glove boxes
• Ducted or canopy connected biosafety
cabinets
• Dunk tanks, pass through autoclaves, facility
sterilization system
• Backflow prevention
Community Design Wish List
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Trained architect/planners/builders
Trained research and safety staff
Initial and ongoing commissioning
Written facility policy manual
Emergency procedures known and practiced
Focus on eliminating community exposure
Not in my backyard!
Engineering Controls
• Primary Barriers
• Mechanical devices that minimize exposure
• Must be applied before work practices and
personal protective equipment
Chemical Fume Hood
• Room air drawn into
front opening
• Direct ducted exhaust
to exterior of building
at roof level
• 100 fpm inflow
velocity
• dilution of toxic,
flammable chemicals
Class I Biosafety Cabinet
• HEPA-filtered fume
hood
• Protects worker and
environment
• No product protection
• inflow velocity 75 fpm
• Exhaust to room or
hard-ducted
Class II Type A1 Biosafety Cabinet
• inflow velocity 100 fpm
• 70% air recirculation
• Protection of worker,
product, and environment
Class II Type B2 BSC
• Total exhaust BSC
• Can use small quantities
of chemicals or
radioactive materials
HEPA-filtered Gloveboxes
Animal Care Containment
• Cage dumping station
• Confinement of
pathogenic waste,
allergens
Clean Bench - Horizontal Flow
• Product protection
only
• Air blown at operator
from across work area
• Not for use with
potential biohazards,
cell culture work, or
allergens
Sharps
• Percutaneous exposure risk
– employ safe work practices
– utilize safe sharp devices
• Aerosol risk
– work practices, containment equipment for confinement
Safe Sharps Devices
Sharps with Integrated Shields
Safer Products
• Mylar wrapped glass
capillary tubes
• Plastic Vacutainers
Other Engineering Controls
• Animal Care & Use
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microisolater cages, ventilated cage racks
ventilated cage racks
poles & collars (NHP’s)
squeeze-back cages
• Spill-clean up
– tongs, forceps, broom & dust pan, manila folder
– paper towels, bench matting
Engineering Controls
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Gasketed blenders, homogenizers
Cotton plugs, filters for flasks in shakers
filtered pipette tips
HEPA and hydrophobic vacuum line filters
Plastic pipettes
Gas burners w/ shield, microincinerator
Centrifuges
– interlock, solid cover, safety buckets, O-rings
Transport Containers
Rigid Medical Waste Containers
• For items that could
puncture a bag
• Never allow to overfill
Reusable Sharps
• Use tongs to handle
• Place in disinfectant
bath
• Use labeled leak-proof
container
• 15 minute decon prior
to handling
• Clean and terminal
disinfection
Plastic for Sharps
• Avoid glass pasteur
pipettes
• Plastic transfer
pipettes
• Plastic aspiration
pipettes
• Other plastic products
Centrifuge Containment
• Load/unload in BSC
• Wait 2 minutes after
run to allow aerosols
to settle
• Decontaminate
centrifuge and buckets
after each use
Mechanical Devices for Sharps
• Keep hands away
from needles
• Use mechanical
methods for removal
• Only use if absolutely
required as part of a
process
Scalpel Removal Device
Confinement at Source
Vacuum System Protection
Medical Waste Receptacles
• Biohazard bags and
boxes
• Sharps containers