Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.
/ Facilities Productive research programs that yield reproducible results depend on laboratory animal-care programs that combine good management and ap- propriate facilities. Such factors as facility location, design, construction, and maintenance influence the quality of animal care and the efficiency of operation. The general guidelines for planning and operating animal facili- ties described below provide a framework in which specific designs and procedures can be implemented on the basis of professional judgment. Minimal standards applying to the housing of guinea pigs and hamsters are published in Animal Welfare Standards (9 CFR 3.25-3.41~. The Good Laboratory Practice Standards apply to the housing of animals used for studying sub- stances regulated by the Food and Drug Administration (21 CFR 58) and the Environmental Protection Agency (40 CFR 160, and 40 CFR 7929. Re- ports prepared by the Institute of Laboratory Animal Resources for the National Research Council, such as this one, supplement the more general information contained in the Guide (NRC, 1996 et seq.~. A series of texts on laboratory animals, sponsored by the American College of Laboratory Animal Medicine, provides specific information about the housing needs of mice, rats, hamsters, and guinea pigs (Baker et al., 1979; Balk and Slater, 1987; Ediger, 1976; Hessler and Moreland, 1984; Lang, 1983; Otis and Foster, 1983; Small, 1983; Wagner and Foster, 19761. The Handbook of Facilities Planning, Volume 2: Laboratory Animal Facilities (Ruys, 1991) addresses such topics as facility planning and basic design principles. Fi- nally, articles having to do with facility design, construction, and manage- ment can be found in various journals and trade magazines. 114
FA CILITIES 115 LOCATION AND DESIGN The location and design of an animal facility depend on the scope of institutional research activities, animals to be housed, need for facility flex- ibility, physical relationship to other functional areas, space availability, and financial constraints. The site and design might further depend on whether the facility is located in space initially constructed for housing animals or in remodeled space. Careful consideration should be given to the location of an animal facil- ity. Initial construction and subsequent operating costs can be influenced by the following: local geologic features; · accessibility of the site; · prevailing winds and other climatic conditions; · availability and adequacy of utility and waste-disposal services; · adjacent properties and buildings; . 'AJAR r--r~ ~ ~ suitability of the site for future expansion or building modification; state and local regulations and codes; and security needs. Initial construction and subsequent operating costs of a facility can usually be minimized by placing support, care, and treatment areas adjacent to animal-housing space and on a single floor. If the facility extends into adjacent buildings, consideration should be given to placing the animal space on the same level and connecting it by a covered, climate-controlled passage to facilitate movement of animals and equipment. Centralization Versus Decentralization In a centralized animal facility, support, care, and treatment areas are adjacent to animal-housing space. The facility usually occupies a single floor or building; if it extends into adjacent buildings, the spaces are con- tiguous. Research personnel come to the animals. In a decentralized facil- ity, areas where animals are housed and used are scattered among rooms, floors, or buildings separated by space that is not dedicated to animal care or support. Animal-housing areas are often adjacent to the laboratories in which the animals are used. In this situation, animal-care personnel come to the animals. Centralization reduces operating costs of a facility because there is a more efficient flow of animal-care supplies, equipment, and personnel; more effi- cient use of environmental controls; and less duplication of support services. Centralization reduces the need to transport animals between housing and study sites, thereby minimizing the risk of disease exposure. It might also
6 RODENTS: LABORATORYANIMAL MANAGEMENT offer greater security by providing more control over access to the facilities and increasing the ease of monitoring staff and animals. A decentralized facility potentially costs more for initial construction because of requirements for environmental systems and controls for separate sites. Multiple cage washers might also be required. Although duplication increases costs, it does provide backups that can be used if a system or equipment fails at one site. Decentrali- zation can reduce traffic at a single site, thereby facilitating disease- or hazard- control or containment programs. Decentralized facilities are generally more accessible to investigators and might offer a more efficent flow of research supplies, equipment, and personnel. Functional Areas In addition to the areas used for actual housing of animals, the Guide (NRC, 1996 et seq.J recommends making provisions for the following: · specialized laboratories or individual areas for such activities as surgery, intensive care, necropsy, radiography, preparation of special diets, experimental manipulation, treatment, and diagnostic laboratory procedures; · containment facilities or equipment if hazardous biologic, physical, or chemical agents are to be used; . . . . . receiving and storage areas for food, bedding, pharmaceuticals and biologics, and supplies; space for the administration, supervision, and direction of the facility; showers, sinks, lockers, and toilets for personnel; an area separate from animal rooms for eating, drinking, smoking, and applying cosmetics; · an area for washing and sterilizing equipment and supplies and, de- pending on the volume of work, machines for washing cages, bottles, glass- ware, racks, and waste cans; a utility sink; an autoclave for equipment, food, and bedding; and separate areas for holding soiled and clean equipment; an area for repairing cages and equipment; and an area to store wastes before incineration or removal. Space Requirements The total space occupied by an animal facility includes program (net) and nonprogram (gross minus net) space. Program space consists of the space allocated to animal housing and various functional areas. Nonprogram space consists of wall thicknesses, dead space, mechanical chases, corri- dors, stairwells, and elevators. The ratio of program to nonprogram space for facilities designed to house rodents and rabbits has been estimated to be 1:1, and the ratio of housing to support space about 2:3 (Ruys, 19911.
FACILITIES 117 Many design factors influence those ratios, and they serve only as gross estimates of space allocation during planning of a facility. The animal- facility program space required in research institutions can be estimated more accurately by considering the number of faculty or staff using ani mals, anticipated animal populations, how the animals wart be used, the health status of the animals, whether animals of differing health status will be used, and the dimensions of caging and support equipment. The size of individual animal-holding rooms should be adequate to accommodate standard equipment, especially caging, and to allow adequate space to service both animals and equipment. Room dimensions also should provide flexibility of use. Rooms of 12 x 20 ft (3.7 x 6.1 m) have been suggested as the most efficient for housing mice, rats, hamsters, guinea pigs, and rabbits (Lang, 1980~. However, room size should be based on the needs of the program. For example, preference might be given to smaller rooms or cubicles because they offer more opportunity to isolate animals by health status or use. Every effort should be made to provide the greatest amount of space for caging. Aisle space should be kept at a minimum but should be sufficient to allow cage changing, rack sanitation, and other hus- bandry manipulations. Relative Relationships of Space The relative relationship of animal rooms, support rooms, and adminis- trative space should be such that traffic from contaminated to clean areas is eliminated and the efficiency of movement of personnel, equipment, sup- plies, and animals is maximized. The location of animal-holding space will be determined to a great extent by the location of cage-sanitation facilities. Corridors, Vestibules, and Anterooms Rooms in an animal facility can be arranged along single or multiple corridors. The single-corridor arrangement provides more efficient use of space and can be as much as 20 percent less expensive to construct and also less expensive to operate than a comparable facility with multiple corridors (Graves, 1990~. A multiple-corridor arrangement allows unidirectional movement, is less congested, and minimizes the potential for cross contamination of the animals. Corridors should be wide enough to facilitate the movement of person- nel and equipment. Although the Guide (NRC, 1996 et seq.) recommends a corridor width of 6-8 ft. single-corridor facilities might require wider corri- dors to reduce congestion. Entry and exit airlocks and anterooms provide transitional areas be- tween corridors and animal space. They can serve as sound barriers and
8 RODENTS: LABORATORY ANIMAL MANAGEMENT should reduce the spread of contaminants and allergens. Although airlocks and anterooms slow movement of personnel, animals, supplies, and equip- ment by doubling the number of doors that must be passed, this slowing provides additional security. Storage of supplies and equipment in airlocks and anterooms should be limited to that essential to support activities in the .. . . . ~ aclJolnlng animal rooms. Interstitial Space Service crews need access to the HVAC system, water lines, drain- pipes, and electric connections. The Guide recommends making these utili- ties accessible through service panels or shafts in corridors outside the animal rooms (NRC, 1996 et seq.~. Another option is to use an interstitial floor on which equipment can be checked or repaired without requiring entry into the animal facility. CONSTRUCTION AND ARCHITECTURAL FINISHES The Guide (NRC, 1996 et seq.) describes construction details and archi- tectural finishes suitable for facilities that house rodents. In general, room surfaces should be moistureproof and free of cracks, unsealed utility penetra- tions, or imperfect junctions that could harbor vermin or impede cleaning. If rooms will be gas sterilized, they should be sealable. The finishes should be able to withstand scrubbing with detergents and disinfectants. All surfaces should be smooth enough to allow rapid removal of water, but floors should have enough traction to be skid-resistant. Surfaces that might be subjected to movement of equipment should be constructed of material that can withstand such movement. Curbs, guardrails, bumpers, door kickplates, and steel rein- forcement of exposed corners help to minimize damage. Exterior windows and skylights are not recommended in animal rooms, because they can con- tribute to unacceptable variations in temperature and photoperiod. MONITORING Within an animal facility, the equipment and systems should be moni- tored to determine whether they are functioning or conforming to predeter- mined limits or guidelines necessary for successful operation. Temperature, humidity, airflow, air-pressure gradients, and illumination (intensity and photoperiod) in individual animal rooms should be checked. To be effec- tive, a monitoring program should provide accurate, dependable, and timely results. The data collected should be reviewed by personnel who are trained to interpret the results, and the results should be provided to those who are authorized to take corrective action.
FACILITIES 119 SPECIAL REQUIREMENTS An animal's health status, genotype, or research use might require that it receive special housing. In addition to conventional animal rooms, vari- ous levels of barrier or containment housing or other specialized housing might be required to minimize variations that can modify an animal's re- sponse to an experimental regimen. Barrier housing isolates animals from contamination. The degree of isola- tion depends on the equipment and procedures used and the design and con- struction of the barrier facility. Rodents usually housed in barrier facilities include microbiologically associated (defined-flora) and specific-pathogen-free rodents, severely immunosuppressed rodents, and transgenic rodents. In a complete barrier system, isolator-maintained animals are intro- duced through entry ports. Equipment and supplies enter through an auto- clave or other sterilization or disinfection system. Personnel enter through a series of locks in which they remove their clothes and shower before donning barrier-room attire. Cage-washing and quarantine space might be included within such a barrier. Partial barriers differ from complete barri- ers in construction features, equipment, or operating procedures. Facilities for animals used in projects that involve hazardous biologic, chemical, or physical agents should be designed so that exposure of person- nel and other animals is minimized or prevented. Biosafety in the Labora- tory (NRC, 1989) describes four combinations of practices, safety equip- ment, and facilities (animal biosafety levels 1-4) recommended for infectious-disease activities in which laboratory animals are used. Conven- tional facilities that are consistent in design and operation with the stan- dards described in the Guide (NRC, 1996 et seq.) also meet the standards for biosafety levels 1 and 2. Levels 3 and 4 require increasing degrees of containment. Rodents are sensitive to noise and should be housed away from noise sources (see Chapter 51. The Guide describes design and construction fea- tures that control noise transmission, including double-door airlocks, con- crete (rather than metal or plaster) walls, the elimination of windows, and the application of sound-attenuating materials to walls or ceilings (NRC, 1996 et seq.~. SECURITY Each facility should consider developing a plan for preventing or mini- mizing the damage or work disruption that can result from a break-in or malicious damage. Procedures adopted should protect animals and person- nel from injury and should protect equipment from theft or damage without creating limitations that adversely affect the quality of care or impede le
120 RODENTS: LABORATORYANIMAL MANAGEMENT gitimate access to the facility. Administrative responsibility for security should be assigned, with the lines of authority clearly delineated. The plan should be reviewed regularly and modified as needed. The number, design, and location of windows and doors influences the ability of a facility manager to control access. At the most basic level, physical security consists of key locks on doors. Computer-controlled card- access systems offer the ability to control and record entrance and egress; however, the computer network should be properly maintained and should be tamperproof. Closed-circuit television and motion monitors complement the efforts of security guards. REFERENCES Baker, H. J., J. R. Lindsey, and S. H. Weisbroth. 1979. Housing to control research variables. Pp. 169-192 in The Laboratory Rat. Vol. I: Biology and Diseases, H. J. Baker, J. R. Lindsey, and S. H. Weisbroth, eds. New York: Academic Press. Balk, M. W., and G. M. Slater. 1987. Care and management. Pp. 61-67 in Laboratory Hamsters, G. L. Van Hoosier, Jr., and C. W. McPherson, eds. Orlando, Fla.: Academic Press. Ediger, R. D. 1976. Care and management. Pp. 5-12 in The Biology of the Guinea Pig, J. E. Wagner and P. J. Manning, eds. New York: Academic Press. Graves, R. G. 1990. Animal facilities: Planning for flexibility. Lab Anim. 19(6):29-50. Hessler, J. F., and A. F. Moreland. 1984. Design and management of animal facilities. Pp. 505-526 in Laboratory Animal Medicine, J. G. Fox, B. J. Cohen, and F. M. Loew, eds. Orlando, Fla.: Academic Press. Lang, C. M. 1980. Special design considerations for animals facilities. Pp. 117-127 in Design of Biomedical Research Facilities. Monogr. Ser. 4. Washington, D.C.: Depart- ment of Health and Human Services. Lang, C. M. 1983. Design and management of research facilities for mice. Pp. 37-50 in The Mouse in Biomedical Research. Vol. III: Normative Biology, Immunology, and Hus- bandry, H. L. Foster, J. D. Smalls and J. G. Fox, eds. New York: Academic Press. NRC (National Research Council), Institute of Laboratory Animal Resources, Committee to Revise the Guide for the Care and Use of Laboratory Animals. 1996. Guide for the Care and Use of Laboratory Animals, 7th edition. Washington, D.C.: National Academy Press. NRC (National Research Council), Board on Chemical Sciences and Technology, Committee on Hazardous Biological Substances in the Laboratory. 1989. Biosafety in the Labora- tory: Prudent Practices for the Handling and Disposal of Infectious Materials. Washing- ton, D.C.: National Academy Press. 222 pp. Otis, A. P., and H. L. Foster. 1983. Management and design of breeding facilities. Pp. 17-35 in The Mouse in Biomedical Research. Vol. III: Normative Biology, Immunology, and Husbandry, H. L. Foster, J. D. Small, and J. G. Fox, eds. New York: Academic Press. Ruys, T., ed. 1991. Handbook of Facilities Planning. Vol. 2: Laboratory Animal Facilities. New York: Van Nostrand Reinhold. 422 pp. Small, J. D. 1983. Environmental and equipment monitoring. Pp. 83-100 in The Mouse in Biomedical Research. Vol. III: Normative Biology, Immunology, and Husbandry, H. L. Foster, J. D. Small, and J. G. Fox, eds. New York: Academic Press. Wagner, J. E., and H. L. Foster. 1976. Germfree and specific pathogen-free. Pp. 21-30 in The Biology of the Guinea Pig, J. E. Wagner and P. J. Manning, eds. New York: Academic Press.