Text Equivalents - Canadian Biosafety Handbook (CBH), Second Edition
A representative diagram of CL2 and CL3 zones includes a CL2 laboratory work area (top left area), a CL2 SA zone (bottom right area), and a CL3 SA zone (top right area). Common basic physical features between all zones are depicted in the diagram. These include a door to separate public, office, and administrative areas (bottom left area) from the containment zone; primary containment devices (e.g., BSCs) located away from high traffic areas and doors; and handwashing sinks provided near the point of exit. Additional features depicted for the CL2 SA zone and CL3 SA zone include anterooms or clothing change areas at entry and exit points. The anteroom in the CL3 SA zone includes a walk-through body shower. The SA zone animal rooms, where animals are housed in primary containment caging, are separated from the laboratory work area by a door. Pass through chambers (optional) in the CL2 SA zone and CL3 SA zone lead to a centralized decontamination area (centre right area), which is a separate CL2 zone. A common support area for freezers and storage (bottom central area) is also shared by the containment zones.
The perimeter of each containment zone coincides with the outermost wall or door. Doors are provided between the public, office, or administrative areas, which are outside the containment zone and have no physical containment requirements, and the corridors leading to the containment zones.
A representative diagram of a CL4 zone is depicted. It contains a laboratory work area across the top of the image, an animal room (SA zone) positioned at the lower right side and an animal cubicle and PM room (LA zone) positioned at the lower left side of the laboratory work area. Dedicated anterooms for personnel entry/exit to the zone are located to the left of the laboratory work area and the left of the LA zone. Both of the anterooms are comprised of a clothing/clean change area, a body shower, a suit/dirty change area, and a chemical shower. The LA zone also contains a separate anteroom at the bottom of the diagram for the entry of animals and equipment into the zone, as well as a separate anteroom for the entry of personnel from the laboratory work area. A gated area (stall) within the LA zone allows for separation of personnel and animals, and the PM room is directly accessed from the LA zone. The perimeter of the CL4 zone coincides with the outermost wall or door to the zone, and anterooms are part of the zone.
This figure depicts a wing of separate rooms (i.e., laboratory work areas, cold room, cell culture room, autoclave room, and office) off the same corridor, with freezers located in the corridor. In Figure 3-3(a), doors to the corridor limit access to the entire wing, such that the entire wing becomes a CL2 zone. In Figure 3-3(b), the same physical space is depicted, but without doors to limit access to the wing corridor. In this configuration, each room (i.e., laboratory work areas, cold room, cell culture room, and autoclave room) is considered a separate CL2 zone, and the corridor and office are outside the CL2 zone.
This figure is an example of a biohazard warning sign. This biohazard warning sign includes the international biohazard warning symbol, containment level, name and telephone numbers of both a primary and alternate contact person, and entry requirements (CBS matrix 3.3). The sign may be further supplemented with additional special provisions for entry, and a list of relevant processes and primary containment equipment used in large scale production areas, or information on other hazards (e.g., chemical, radioactive) present in the containment zone.
This figure depicts the same CL2 containment zone in which an office is only accessible from the laboratory work area. Configuration (a) illustrates a CL2 zone that includes both the laboratory work area and the office space. Configuration (b) illustrates the same physical space, but with the office excluded from the containment zone. This configuration requires additional elements such as posting biohazard signage on the office door, keeping the office door closed, and following appropriate PPE protocols for entry to and exit from the office, in order to be compliant with the CBS requirements.
This figure depicts a CL3 SA zone. The zone is accessed through an anteroom at the upper left, which includes a storage area, a clean change area, a walk-through body shower, and a dirty change area. The laboratory work area, accessed from the anteroom, includes a cold storage area with freezers and liquid nitrogen, an area dedicated to paper and computer work, BSCs, and a double-door autoclave and pass-through chamber that cross the containment barrier. The animal room on the lower left side is accessed from the laboratory work area. The containment zone perimeter coincides with the outermost walls of the zone, including the anteroom. The containment barrier coincides with the containment zone perimeter, except in the anteroom, where it coincides with the inner (containment zone side) wall of the clean change room and storage area, and the shower door leading to the clean change area.
The figure shows a CL3 LA zone that includes a laboratory work area (top), two animal cubicles (lower left), and a PM room (lower centre). The containment zone is accessed through an anteroom at the top left with a clean change area, a walk-through body shower, and a dirty change area, that leads to the laboratory work area. Each cubicle and the PM room can be accessed from the laboratory work area through their own anterooms, which include a clean change area, a walk-through body shower, and a dirty change area. The animal cubicles and PM room can also be accessed through the dirty corridor (bottom of image), which is accessed through another anteroom from the laboratory work area. The bottom right corner also has an anteroom leading from outside the zone into the dirty corridor for animal entry. The containment zone perimeter coincides with the outermost walls of the entire zone, including anterooms leading into the zone. The containment barrier of the containment zone coincides with the perimeter, except in the anteroom where it coincides with the inner (containment zone side) wall of the clean change area and storage area, and the shower door leading into the clean change area. An additional (inner) containment barrier exists that surrounds the dirty corridor, the outside of the animal entry anteroom, the animal cubicles and the PM room, and the anterooms to the animal areas, except in the anterooms where it coincides with the inner (cubicle, PM room, or dirty corridor side) wall of the clean change area, and the shower door leading into the clean change area.
The image depicts an anteroom, which includes a clean change area, walk-through body shower, and dirty change area, and a CL3 work area, in order to identify the critical door on the containment barrier, and the combinations of doors needing to be interlocked.
Door “A” on the left of the image leads to the “clean” change area of the anteroom from outside the containment zone. Door “B”, which opens from the clean change area and leads into the walk-through body shower, is the critical door that separates the “clean” and “dirty” change areas. Door “C”, to the right, leads to the CL3 work area (i.e., a laboratory work area, an animal room, an animal cubicle, a PM room, or a large scale production area). In order to mitigate the migration of air from the “dirty” change area to the “clean” change area or outside the containment zone, critical door “B” would have to be interlocked or otherwise protected against simultaneous opening with door “A” (i.e., “A+B” and “B+A”). In order to mitigate the migration of air from the CL3 work area through the “dirty” change room and into the “clean” change area, critical door “B” would have to be interlocked with or otherwise protected against simultaneous opening with door “C” (i.e., “B+C” and “C+B”).
This figure presents a matrix for determining the level of risk based on the likelihood of an event occurring and the consequences of the event should it occur. Each axis goes from very low to very high.
This figure depicts the front and back of an example of an emergency medical contact card. The front of the card contains the card holder’s name, the date of issue, a summary of the infectious materials or toxins that are handled by the individual and whether the card holder is working with non-human primates. In addition, a statement reads “This card is to be kept in the possession of the laboratory employee and presented to a physician if an illness occurs that may be associated with a pathogen used within the laboratory (see reverse)”. The back of the card contains the name and address of the facility where the individual works as well as the name, and work and home telephone numbers for two emergency contacts. In addition, a short statement reads “To the physician – this employee works in an environment where pathogenic microorganisms are present. Please contact the individuals listed below for information on the agents to which this individual may have been exposed”.
The figure shows air ducts leading into and out of a housing that contains a HEPA filter. There are dampers on the ducts to either side of the housing to allow for the decontamination of the filter. A door on the housing allows access for changing the filters and the cutaway shows the location of the filters. An inset shows the filter media: a pleated sheet of fibres divided by separators that provide rigidity.
In this figure, a Class one BSC is hard-ducted and functions using the building’s HVAC system. Room air is drawn through the front opening of the cabinet and moves across the negatively-pressurized workspace. It is then drawn through an air grille situated at the rear of the cabinet, flows up a plenum and through a HEPA filter before being discharged to the outside environment.
In this figure, a Class one BSC is shown with a motor and blower assembly. Room air is drawn through the front of the cabinet and moves across the negatively-pressurized workspace. It is then drawn through an air grille situated at the rear of the cabinet, flows up a plenum and through a HEPA filter before being discharged into the containment zone.
In this figure, a Class two Type A-one BSC is shown with a thimble connection and a positively-pressured plenum. HEPA-filtered air from the top of the cabinet flows downwards towards the work surface. Above the work surface and halfway between the front and rear grilles, the filtered downflow air splits in two. One half of the downflow air passes through the front grille while the other half passes through the rear grille. Room air is also drawn into the front grille. The room air and downflow air are drawn through the grilles and into the negatively-pressured chamber underneath the work surface. The air is then drawn through the blower, pushed into the positively-pressured plenum and flows to the top of the cabinet. A portion of this air passes through the HEPA filter in the plenum before being recirculated towards the work area. The other portion passes through the HEPA filter located at the base of the thimble connection and is exhausted into the containment zone or to the outside atmosphere through the thimble connection. The Type A-one BSC shown contains a positively-pressured contaminated plenum.
In this figure, the BSC contains a thimble connection, and a positively-pressured contaminated plenum (between the blower and HEPA filters) surrounded by a negatively-pressured plenum. HEPA-filtered air from the top of the cabinet flows downwards towards the work surface. Above the work surface and halfway between the front and rear grilles, the HEPA-filtered downflow air splits in two. One half of the downflow air passes through the front grille while the other half passes through the rear grille. Room air is also drawn into the front grille. The room air and downflow air is drawn through the grilles and flows up the negatively-pressured plenum, through the blower, and into the positively-pressured plenum (between the blower and HEPA filters) at the top of the BSC. A portion of this air passes through the HEPA filter in the plenum before being recirculated towards the work area. The other portion passes through the HEPA filter located at the base of the thimble connection and is exhausted into the containment zone or directly to the outside atmosphere through the thimble connection.
In this figure, a Class two Type B-one BSC is shown with a hard-ducted connection to the building’s HVAC system. HEPA filtered air from the plenum flows downward and splits into two streams directly above the work surface, halfway between the front and rear grilles. The air drawn through the grilles is drawn through a HEPA filter by the blower and is pushed up thee plenums to the top of the BSC. A portion of HEPA filtered air flows downwards over the work area while the other portion flows through a HEPA filter before being exhausted out of the BSC to the outside atmosphere.
In this figure, a Class two Type B-two BSC is shown with a hard-ducted connection to the building’s HVAC system. A supply blower pushes room air into the top of the cabinet. The contaminated air in the plenum remains physically separated from the room air from the supply blower. Room air is pushed into the top of the cabinet by the supply blower and is directed through the HEPA filter before being discharged downward into the cabinet work space. The downflow air splits into two streams directly above the work surface, halfway between the front and rear grilles. Room air is also drawn through the front grille before it can reach the work surface. The air directed through the grilles is drawn into the negatively-pressured plenum and flows to the top of the cabinet. It then passes through the HEPA filter and is directly vented to the outside atmosphere.
In this figure, a Class three BSC is shown with hard ducted supply and exhaust air. The BSC is completely enclosed; all penetrations are air-tight, and the BSC is kept under negative pressure. Manipulations are performed through attached heavy-duty long-sleeved gloves. Supply air is HEPA-filtered before entering the cabinet and circulates within the work space. The air from the work space is drawn into the exhaust duct and passes through two consecutive HEPA filters before being vented to the outside atmosphere.
This figure depicts two rooms in which BSCs are installed. In Figure 12-7(a), two BSCs are located along one wall, and two others along two of the other walls. These BSCs are well-located BSCs, respecting minimum recommended clearances from the doorway and between each of the other BSCs installed in the room. Specific BSCs may have different recommended clearances to prevent airflows from a neighbouring BSC from interfering with the protective air curtain. Figure 12-7(b) illustrates poorly-located BSCs in a different room layout. In this case, the two BSCs are located side by side along a wall, close to a door, and where traffic, the doorway, and the neighbouring BSC are likely to disrupt the protective air curtain, and compromise personal, environmental, and product protections. In addition, the figure shows two persons wording in one of the BSCs. Class II BSCs are designed and certified use by a single individual only.
This figure shows a BSC set up for work, with clean reagents and pipets placed to the left, a rack with tubes in the middle, solid and liquid waste containers to the back and right, and a waste tray for pipets to the right. A vortex mixer is placed towards the back of the work area, and a cordless pipetting device near the centre, beside the rack. The direction of workflow goes from the “clean” side (i.e., less contaminated) to the “dirty” side (i.e., higher contamination).
In this diagram, liquid from a conical centrifuge tube is aspirated through a tube into a conical flask containing a disinfectant solution used for the collection and decontamination of liquid waste. This flask is connected via a hose to a second flask, which also contains disinfectant, and is used to collect any overflow and to trap aerosols. The vacuum source in this illustration is a portable vacuum pump. It is protected against infectious aerosols or aerosolized toxins through the use of an in-line filter, in this case a 0.2 µm filter, connected between the overflow flask and the vacuum source.
This figure depicts a 3D rendering of an animal room in which two wheeled ventilated cage racks can be seen. The inset shows a close-up view of a ventilated cage rack and a primary containment cage with a filter top.
Figure 13-2(A) depicts a more detailed view of an example of a ventilated caging system. The system consists of a ventilated cage rack that supplies a source of filtered air into the individual cages, or microisolators. The cage rack has a ventilation system and a grid-like frame into which the individual cages are inserted.
This figure provides a detailed illustration of a typical wire cage (non-filtered) used to house small-sized animals, such as nonhuman primates or raccoons, in an animal cubicle. This type of cage confines the animal to a small space within the cubicle but provides no containment of pathogens.
Figure 13-4(a) depicts a 3D rendering of an animal cubicle containing multiple open cages (non-filtered wire cages) along one wall of the cubicle. This configuration is suitable to house animals such as dogs, cats, racoons, or nonhuman primates.
Return to Figure 13-4b
Figure 13-5: Representative Diagram of Single Corridor and Dual Corridor Designs for Animal Containment Zones
Figure 13-5(a) features a single corridor design of an animal containment zone appropriate for CL2-Ag or CL3-Ag. The single corridor across the middle is considered “dirty”. The containment zone is accessed by personnel through an anteroom located off the corridor (entry/exit). The entry of infected animals into the containment zone is through a separate anteroom located off the corridor. Each animal cubicle and PM room within the containment zone is accessed by personnel from the corridor via separate anterooms (entry/exit).
Figure 13-5(b) depicts a dual corridor design for a CL2-Ag or CL3-Ag area where there are separate “clean” and “dirty” corridors. In this layout, animal cubicles and post-mortem rooms are located between a clean and dirty corridor. The entry and exit of personnel and uninfected animals into the containment zone occurs through anterooms located off of the “clean” corridor. Infected animals may only enter the containment zone from an anteroom located off of the “dirty” corridor. Each animal cubicle and PM room within the containment zone is accessed through an anteroom off of the “clean” corridor. There are also entry/exit points from the “dirty” corridor to each animal cubicle and PM room.
Note that for CL2-Ag, an anteroom is only required at one of the following; either at the entry/exit to the containment zone, or into each animal cubicle or PM room. For more detail, refer to Section 3.7.
This figure depicts the various incidents involving pathogens and toxins, and shows those that can lead to exposure, which include: personal injury or illness; spill; animal escape; release; unauthorized entry into the containment zone; power failure; fire or explosion; flood or other crisis situation. Missing infectious material or toxin is the one incident that does not lead to exposure. Laboratory acquired infections and intoxications are depicted as a subset of exposures.
If an incident involved an RG3, RG3, or RG4 pathogen or toxin, and there is reason to believe that the incident involved one or more individuals’ contact with, or close proximity to, infectious material or toxins that may result in infection or intoxication – that is, exposure via inhalation, ingestion, inoculation, or absorption – then an exposure occurred and an exposure notification report is to be prepared and submitted without delay, and an exposure follow-up report submitted within 30 days, or in the case of an SSBA, within 15 days. If the incident did not involve an RG2, RG3, or RG4 human pathogen or toxin, or if there is no reason to believe that contact or close proximity with pathogens or toxins may have resulted in infection or intoxication, then best practice dictates that the incident be documented internally within the facility in the event that the information is needed for recall or reassessment at a later date.
If a disease is detected and there is reason to believe that it may be linked to an exposure in the containment zone setting, then it is classified as an LAI and a previously missed or unreported exposure. In such a case, an exposure notification report and follow-up report are to be prepared and submitted as described above. If there is no reason to believe that the disease may be linked to the containment zone, then exposure is ruled out and there is no further action required.
In most cases, a disease state will include recognition of an illness, syndrome, or known disease. However, some facilities may employ medical surveillance practices that could identify a seroconversion, which may provide an additional source of information for recognition of infection or disease states.
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