COMPARATIVE LEUKEMIA RESEARCH 1973, LEUKEMOGENESIS, BIEL. HAEMAT., NO. 40, ED. Y. PTO AND R. M. DUTCHERt, UNIV. 0F TOKYO PRESS, TOKYO/KARGER, BASEL PP. 779-782 (1975)
Protection against Biohazards in Animal Laboratories
J. KAWAMATA and T. YAMANOUCHI
Quarters for Experimentally Infected Animals, Research Institute for Microbial Diseases, Osaka University*
Protection against biohazards in animal laboratories is an essential problem not only for experimental cancer research but also for experimental studies on infectious agents * Yamada-kami, Suita, Osaka 565, Japan.
Downloaded by: Université de Paris 193.51.85.197 - 2/1/2020 8:50:08 AM
An outline of the animal facilities known as the "Quarters for Experimentally Infected Animals" of the Research Institute for Microbial Diseases, Osaka University, is presented as one example of the approaches used for protecting against biohazards in animal laboratories. The quarters are contained in a 2-story building which is in the form of small cubicles for housing the experimentally infected animals. Each cubicle is equipped with specially designed cabinet compartments in which the animal cages are placed. The anterior surface of the compartments consists of an outward inclining door. Vigorous air-mixing between compartments and the interiors of the cubicles can be avoided by this arrangement. The air for ventilation is sucked through a gap between the edge of the door and the wall of each compartment and the collected air is finally filtered through Cambridge "Aerosolve" and "Absolute" filters before being exhausted into the atmosphere. In the central corridor connecting each cubicle the air pressure is maintained at a higher level than that in the cubicle but lower than that outdoors. Thus, the air stream is always kept flowing from the outside to the inside of the cubicle and from the inside of the cubicle to the compartments but never vice versa. Each cubicle is equipped with an individual, pass-through autoclave. All soiled materials are sterilized before being removed from the cubicle. The drained water from each cubicle is chlorinated in a tank by chloride of lime. In these facilities experimentally infected animals can be handled with little danger of accidental contamination of personnel, other animals, or the external environment. The authors emphasize the importance of complete adherence to the rules in such animal facilities.
780
KAWAMATA/YAMANOUCHI
in general. The Research Institute for Microbial Diseases, Osaka University, consists of 15 departments in the research section including virus, bacteriology, immunology, parasitology, chemotherapy research, and oncological laboratories. The research subjects in these laboratories consist of experimental infection of animals by various pathogenic viruses, including tumor viruses, and by bacteria and parasites. In the old building of the institute located in downtown Osaka, several small, individual animal rooms for experimentally infected animals were provided. The facilities, however, were not sufficient. As a result, the scale of the experiments was small, and the species of pathogenic microorganisms used were limited considering the possible danger of biohazards. When the new building of the institute was being constructed in the suburbs of Osaka in 1966, new animal facilities were planned specially designed for experimental infection with little danger of biohazards. In this paper an outline of the animal facilities of this institute is presented as one example of the approaches used for protecting against biohazards in animal laboratories.
The principles used in the design of the new animal facilities were aimed at protecting the personnel and other research animals from accidental laboratory infection. Protection from contamination of the external environment was another important principle. New animal facilities known as the "Quarters for Experimentally Infected Animals" were constructed on the basis of these principles. These quarters are contained in a 2-story, reinforced concrete structure adjacent to the main building of the institute and connected to it by a short corridor. The quarters contain approximately 1,300 m2 of floor space, are air conditioned by totally fresh, filtered air through a Cambridge "Aerosolve" filter, and possess many special features for safe handling of pathogenic microorganisms. For housing the experimentally infected animals, the ground floor of the building is in the form of 17 cubicles 2 X 6 m each and 2 cubicles 4 X 6 m each on both sides of a central corridor (Fig. 1). Each cubicle is equipped with 4 or more sets of cabinet compartments in which the animal cages are placed. The cabinets were designed according to an original model developed by Lind (1958) (Fig. 2). The cabinet compartments are made of sheet metal, and each cabinet contains 6 or 8 compartments. The back and top walls are double, and the resulting space is connected with every compartment via small holes punched in the back walls. The top of this space is connected to an air evacuation channel via a prefilter box attached to the top of the cabinets. The anterior surface of the compartments consists of an outward inclining door made of a translucent plastic panel. The door is drawn up when feeding the animals or when a cage is removed. Vigorous air-mixing between compartments and the interior of the cubicles can be avoided with this arrangement. The air for ventilation is sucked through a gap between the edge of the plastic door and the wall of the cabinet compartments. The ventilated air exhausted from each cabinet is collected and sucked up by a blower in the penthouse and finally filtered through Cambridge "Aerosolve" and "Absolute" filters. The cleaned air is then exhausted into the atmosphere. The air pressure in the central corridor is controlled so as to maintain a higher level than in the cubicle but lower than that
Downloaded by: Université de Paris 193.51.85.197 - 2/1/2020 8:50:08 AM
General Design and Direction for Use of the Facilities
BIOHAZARD PROTECTION IN ANIMAL LABORATORIES
781
ε
o o
Ι o
.ε 0 Q
Α
Q
Isolator room
Isolator room
o o
C 1-1
-
ΒathroomToilet Lounge
Lobby Dumb-waiter
Office
1111111
Lobby 1 2 3 4 5m
of the ground floor of the quarters. A: Pass-through autoclave.
outdoors. Thus, the air stream is always kept flowing from the outside to the inside of the cubicle and from the inside of the cubicle to the cabinet but never vice versa. A parallel filter system is provided to assure continuous air filtering. If there is any trouble in the filter system on one side, we can switch to the other side. Sterilization of the filter by disinfectant is also facilitated by operating the system alternately without any interruption in air filtration. Power supplies for the air supply and exhaust system are guaranteed by an independent generator. The drainage from each cubicle is collected in an underground tank, and the drained water is chlorinated by chloride of lime. Another particular feature of these quarters is that each cubicle is equipped with an individual, pass-through autoclave. All soiled materials are sterilized before being removed from the cubicle. When we work in the cubicle, we put on a long-sleeved operating gown over a sleeveless gown, and a cap, mask, and pairs of rubber gloves and boots. Before leaving the cubicle we take them Off, and they are sterilized in the autoclave, except for the rubber gloves and boots which are soaked in a solution of disinfectant. After sterilization in an autoclave, the carcasses of animals are incinerated.
Downloaded by: Université de Paris 193.51.85.197 - 2/1/2020 8:50:08 AM
FIG. 1. Plan
782 KAWAMATAIYAMANOUCHI
FIG. 2. Schematic illustration of the cabinet compartments.
Discussion and Conclusion In these specially designed quarters, experimentally infected animals can be handled with little danger of accidental contamination of personnel, other research animals, or the external environment. We do not consider, however, the design of our animal quarters as the only approach to the protection against biohazards in animal laboratories. The design should depend upon the kind of pathogenic microorganisms being used and the animal experiments planned. Finally, we should like to emphasize that not only the design and equipment but also complete adherence to the rules is important. Even if facilities are very well designed, there will often be the danger of spreading biohazards if personnel do not follow the rules. REFERENCE
Downloaded by: Université de Paris 193.51.85.197 - 2/1/2020 8:50:08 AM
LIND, A. Danger of TB infection to personnel in pathological laboratories. Transaction of the NAPT Commonwealth Chest Conference, National Association for the Prevention of Tuberculosis, London (1958).
Protection against Biohazards in Animal Laboratories
J. KAWAMATA and T. YAMANOUCHI
Quarters for Experimentally Infected Animals, Research Institute for Microbial Diseases, Osaka University*
Protection against biohazards in animal laboratories is an essential problem not only for experimental cancer research but also for experimental studies on infectious agents * Yamada-kami, Suita, Osaka 565, Japan.
Downloaded by: Université de Paris 193.51.85.197 - 2/1/2020 8:50:08 AM
An outline of the animal facilities known as the "Quarters for Experimentally Infected Animals" of the Research Institute for Microbial Diseases, Osaka University, is presented as one example of the approaches used for protecting against biohazards in animal laboratories. The quarters are contained in a 2-story building which is in the form of small cubicles for housing the experimentally infected animals. Each cubicle is equipped with specially designed cabinet compartments in which the animal cages are placed. The anterior surface of the compartments consists of an outward inclining door. Vigorous air-mixing between compartments and the interiors of the cubicles can be avoided by this arrangement. The air for ventilation is sucked through a gap between the edge of the door and the wall of each compartment and the collected air is finally filtered through Cambridge "Aerosolve" and "Absolute" filters before being exhausted into the atmosphere. In the central corridor connecting each cubicle the air pressure is maintained at a higher level than that in the cubicle but lower than that outdoors. Thus, the air stream is always kept flowing from the outside to the inside of the cubicle and from the inside of the cubicle to the compartments but never vice versa. Each cubicle is equipped with an individual, pass-through autoclave. All soiled materials are sterilized before being removed from the cubicle. The drained water from each cubicle is chlorinated in a tank by chloride of lime. In these facilities experimentally infected animals can be handled with little danger of accidental contamination of personnel, other animals, or the external environment. The authors emphasize the importance of complete adherence to the rules in such animal facilities.
780
KAWAMATA/YAMANOUCHI
in general. The Research Institute for Microbial Diseases, Osaka University, consists of 15 departments in the research section including virus, bacteriology, immunology, parasitology, chemotherapy research, and oncological laboratories. The research subjects in these laboratories consist of experimental infection of animals by various pathogenic viruses, including tumor viruses, and by bacteria and parasites. In the old building of the institute located in downtown Osaka, several small, individual animal rooms for experimentally infected animals were provided. The facilities, however, were not sufficient. As a result, the scale of the experiments was small, and the species of pathogenic microorganisms used were limited considering the possible danger of biohazards. When the new building of the institute was being constructed in the suburbs of Osaka in 1966, new animal facilities were planned specially designed for experimental infection with little danger of biohazards. In this paper an outline of the animal facilities of this institute is presented as one example of the approaches used for protecting against biohazards in animal laboratories.
The principles used in the design of the new animal facilities were aimed at protecting the personnel and other research animals from accidental laboratory infection. Protection from contamination of the external environment was another important principle. New animal facilities known as the "Quarters for Experimentally Infected Animals" were constructed on the basis of these principles. These quarters are contained in a 2-story, reinforced concrete structure adjacent to the main building of the institute and connected to it by a short corridor. The quarters contain approximately 1,300 m2 of floor space, are air conditioned by totally fresh, filtered air through a Cambridge "Aerosolve" filter, and possess many special features for safe handling of pathogenic microorganisms. For housing the experimentally infected animals, the ground floor of the building is in the form of 17 cubicles 2 X 6 m each and 2 cubicles 4 X 6 m each on both sides of a central corridor (Fig. 1). Each cubicle is equipped with 4 or more sets of cabinet compartments in which the animal cages are placed. The cabinets were designed according to an original model developed by Lind (1958) (Fig. 2). The cabinet compartments are made of sheet metal, and each cabinet contains 6 or 8 compartments. The back and top walls are double, and the resulting space is connected with every compartment via small holes punched in the back walls. The top of this space is connected to an air evacuation channel via a prefilter box attached to the top of the cabinets. The anterior surface of the compartments consists of an outward inclining door made of a translucent plastic panel. The door is drawn up when feeding the animals or when a cage is removed. Vigorous air-mixing between compartments and the interior of the cubicles can be avoided with this arrangement. The air for ventilation is sucked through a gap between the edge of the plastic door and the wall of the cabinet compartments. The ventilated air exhausted from each cabinet is collected and sucked up by a blower in the penthouse and finally filtered through Cambridge "Aerosolve" and "Absolute" filters. The cleaned air is then exhausted into the atmosphere. The air pressure in the central corridor is controlled so as to maintain a higher level than in the cubicle but lower than that
Downloaded by: Université de Paris 193.51.85.197 - 2/1/2020 8:50:08 AM
General Design and Direction for Use of the Facilities
BIOHAZARD PROTECTION IN ANIMAL LABORATORIES
781
ε
o o
Ι o
.ε 0 Q
Α
Q
Isolator room
Isolator room
o o
C 1-1
-
ΒathroomToilet Lounge
Lobby Dumb-waiter
Office
1111111
Lobby 1 2 3 4 5m
of the ground floor of the quarters. A: Pass-through autoclave.
outdoors. Thus, the air stream is always kept flowing from the outside to the inside of the cubicle and from the inside of the cubicle to the cabinet but never vice versa. A parallel filter system is provided to assure continuous air filtering. If there is any trouble in the filter system on one side, we can switch to the other side. Sterilization of the filter by disinfectant is also facilitated by operating the system alternately without any interruption in air filtration. Power supplies for the air supply and exhaust system are guaranteed by an independent generator. The drainage from each cubicle is collected in an underground tank, and the drained water is chlorinated by chloride of lime. Another particular feature of these quarters is that each cubicle is equipped with an individual, pass-through autoclave. All soiled materials are sterilized before being removed from the cubicle. When we work in the cubicle, we put on a long-sleeved operating gown over a sleeveless gown, and a cap, mask, and pairs of rubber gloves and boots. Before leaving the cubicle we take them Off, and they are sterilized in the autoclave, except for the rubber gloves and boots which are soaked in a solution of disinfectant. After sterilization in an autoclave, the carcasses of animals are incinerated.
Downloaded by: Université de Paris 193.51.85.197 - 2/1/2020 8:50:08 AM
FIG. 1. Plan
782 KAWAMATAIYAMANOUCHI
FIG. 2. Schematic illustration of the cabinet compartments.
Discussion and Conclusion In these specially designed quarters, experimentally infected animals can be handled with little danger of accidental contamination of personnel, other research animals, or the external environment. We do not consider, however, the design of our animal quarters as the only approach to the protection against biohazards in animal laboratories. The design should depend upon the kind of pathogenic microorganisms being used and the animal experiments planned. Finally, we should like to emphasize that not only the design and equipment but also complete adherence to the rules is important. Even if facilities are very well designed, there will often be the danger of spreading biohazards if personnel do not follow the rules. REFERENCE
Downloaded by: Université de Paris 193.51.85.197 - 2/1/2020 8:50:08 AM
LIND, A. Danger of TB infection to personnel in pathological laboratories. Transaction of the NAPT Commonwealth Chest Conference, National Association for the Prevention of Tuberculosis, London (1958).
