D.1 Space Requirements
D.2 Furniture and Equipment
D.3 Architectural Finishes and Materials
D.4 Structural
D.5 Heating, Ventilation, and Air Conditioning (HVAC)
D.6 Plumbing
D.7 Electrical
D.8 General Health and Safety
D.9 Biosafety
D.10 Radiation Safety
D.11 Animal Facility Fire Protection
D.12 Animal Facility Pest Management

D.1 Space Requirements

The space requirements for animal facilities vary greatly. Requirements are dependent on the specific use of the facility, type and density of animals housed, type of caging and racking systems, number of investigators utilizing the facility, and operational methodologies of the facility. Each proposed facility will require careful analysis by the design team and consultation with users to determine adequate space requirements.

D.1.1 Space Planning Criteria: Criteria for animal housing space are set forth in The Guide. The space requirements for a facility should consider the total animal population, number of species, isolation requirements, number of animals per room, and number of investigators and research projects anticipated. The assignment of support space is based on protocol, equipment, and process and can be determined only on the basis of an evaluation of the specific project program of the facility users. Application of these space criteria requires the design team to analyze functional requirements in light of specific project needs.

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D.2 Furniture and Equipment

D.2.1 Casework and Countertops: Cantilevered benchtops with rolling metal cabinets are preferred because they allow for ease of cleaning. Fixed casework and countertops shall be sealed to walls and floors during installation to minimize harborage of pests and provide a cleanable joint. Countertop materials will vary depending on usage. Traditional materials such as chemical-resistant plastic laminates may be appropriate for some applications. Epoxy resin will apply for most applications where corrosive chemicals are used or sinks or heavy water usage occurs. Other new materials should be investigated for costeffectiveness and durability. Stainless steel shall be used for glass-washing areas and other areas, depending on program requirements.

D.2.2 Chemical Fume Hoods and Biological Safety Cabinets: Chemical fume hoods are generally not required in an animal facility. However, there are certain types of animal research that may require the use of a fume hood. An example of this is the use of highly mutagenic chemicals to induce mutations in zebrafish. The determination to include a fume hood within the boundary of the animal facility should be made with the representative users of the facility. Consideration should be given to providing fume hoods in a small percentage of the procedure rooms. For detailed information on fume hoods, see General Design Guidelines, Mechanical.

Biosafety cabinets (BSCs) may be used in some animal holding rooms in lieu of a laminar flow changing station. BSCs may also be used in procedure/treatment rooms. The determination to include a BSC in either location should be made with the representative users of the facility. National Sanitation Foundation Standard 49 and NIH Division of Safety criteria and standard details regarding BSC design shall be used.

D.2.3 Equipment: The planning and design for equipment is a multidisciplinary task that should begin during the planning phases and be coordinated throughout design. The A/E shall plan the facility to accommodate current and anticipated equipment requirements. A wide variety of equipment is utilized throughout NIH animal facilities. For additional requirements for specific room functions, see Animal Research Facilities, Section: Space Descriptions. Washing and sterilizing equipment in animal facilities shall be steam powered. Requirements will be program driven and verified with the users.

D.2.4 Autoclaves: Space for autoclave capacity should be provided on the “dirty” side of the facility for decontamination of cages, waste materials, and other contaminated equipment. The autoclave provided may be double-door/pass-through. The doors should be interlocked to prevent the possibility of contamination of the “clean” side. Space should be provided for autoclave maintenance. Space should also be considered for “clean” autoclaves (for sterilization of microbiological media and clean instruments, etc.) when required by animal facility personnel.

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D.3 Architectural Finishes and Materials

The animal facility shall be constructed of materials and finishes that are impervious and monolithic and resistant to cracking and damage to meet the demands of heavy cart traffic, frequent cleaning with the use of high-pressure, high-temperature water, abrasives, and caustic cleaners, including chlorine compounds. Finishes shall also be selected to contribute to the creation of a comfortable, productive, and safe work environment.

Finishes and construction details shall be well developed to provide a positive barrier against the harborage of pests and vermin. Structural joints should be detailed to be easily cleaned and decontaminated. The construction documents shall indicate the requirement for caulking and sealing all penetrations to close off harboring places for pests. All joints between dissimilar materials shall be accessible and easily cleanable or caulked to provide a sealed barrier. Selection of materials and penetrations through walls and floors shall be coordinated with the NIH Division of Safety. For additional requirements, see General Design Guidelines, Section: Fire Protection and Section: Pest Management, for requirements unique to an animal facility.

D.3.1 Floor Treatments: Floors should be smooth, durable, moisture-proof, non-absorbent, and slip-resistant and resistant to the adverse effects of disinfectants, high-temperature water, and detergent cleaning, as well as chemicals used in holding and procedure rooms and continuous movement of cages and equipment. If thresholds are used to separate dissimilar flooring materials, they should be of a type that permits the easy wheeling of cages or other equipment through the animal facility. All exposed concrete floors shall be sealed.

D.3.1.1 Moisture Protection and Waterproofing: All “wet” areas should receive a positive slope to the drain of 6 mm per 300 mm. Lesser slopes and flat areas are subject to ponding, which results in deterioration of the finish floor. Standing water can also pose a significant safety hazard and creates problems with sanitation. Floors should receive a waterproof membrane prior to the installation of the finish materials. The selection of the membrane system should be coordinated with the flooring manufacturer.

D.3.1.2 Resinous Epoxy Flooring Materials: Resinous epoxy flooring is recommended for all floors within animal facilities that are subject to abuse, frequent cleaning, and continuous movement of cages and equipment. Areas that are hosed down shall be surfaced with resinous flooring materials. Flooring material should be carried up the walls a minimum of 150 mm to provide an integral covered base for ease of cleaning. A water vapor transmission test is required for all projects at the NIH prior to installing resinous epoxy flooring materials to any concrete substrate. For additional requirements, see General Design Guidelines, Section: Architectural. Resinous epoxy flooring shall conform to NIH Division 9 Specification Section “Resinous Flooring.”

D.3.1.3 Sheet Vinyl: Some areas within the animal facility may not require the same amount of cleaning and disinfecting as the areas in which cages and animals are held or transported. These areas are program driven and may consider the use of a monolithic sheet vinyl flooring material. Flooring material should be carried up the walls a minimum of 150 mm to provide an integral covered base for ease of cleaning.

D.3.2 Wall Treatments: Walls shall be free from cracks, unsealed penetrations, or imperfect junctions with ceilings and floors. Walls shall be capable of withstanding the impact of cages, carts, and racks. Walls shall also provide a smooth, moisture-resistant surface. Many areas within an animal facility are subject to water daily, including impact damage from hose streams. Walls in these areas should be constructed of concrete block or surfaced with a heavy duty, impenetrable veneer.

D.3.2.1 Concrete Masonry Units (CMUs): If concrete masonry is selected for the wall finish material, it should be sealed with two coats of epoxy block filler before the application of epoxy finish coating systems. Failure to provide this surface preparation will result in a porous, pinhole-filled surface that is difficult to clean. All CMU joints shall be tooled flush to avoid the collection of dirt prior to the application of block filler. CMU walls shall be painted with at least two finish coats.

D.3.2.2 Gypsum Wallboard (GWB): High-density, water-resistant GWB is an appropriate wall material and should be evaluated on the basis of program and cost requirements. If GWB is selected as the wall material, bumper guards/rails shall be provided at multiple heights on all walls in corridors and animal holding rooms to prevent damage from cages, racks, and handcarts.

D.3.2.3 Ceramic Tile and Glazed Block: Ceramic tile and glazed block are not permitted because of the number of exposed joints, which increases both the possibility of failure and the opportunity for dirt to collect.

D.3.2.4 Fiberglass Reinforced Panels (FRPs): The use of FRPs in animal holding rooms should be considered when determining finishes for the animal facility. Issues such as durability, life-cycle cost, and maintenance are factors to be evaluated when comparing finishes.

D.3.2.5 Bumper/Wall Guards and Corner Guards: Extensive use of bumper/wall guards and corner guards is required throughout an animal facility regardless of the wall construction to minimize impact-related wall damage. Only solid materials that can withstand moisture and cleaning shall be specified. Hollow products should not be considered since the void cannot be cleaned and provides harborage for pests. Wall guards should be designed to protect door frames wherever possible by returning the ends into the frame. Guards should be provided in a high-low configuration in all corridors and cagewash areas to protect walls from damage by mobile equipment of various sizes. Stainless steel corner guards should be used at all external corners in corridors, animal rooms, and other spaces subject to impact damage. Wall and corner protection should be sealed to the
mounting surface with proper sealant at time of installation.

D.3.3 Ceiling Treatments: All areas within the animal facility, except personnel support spaces, require ceilings that are smooth, free of crevices and imperfect junctions with walls, and capable of withstanding scrubbing with detergents, disinfectants, and water under pressure on a frequent basis. Surface-mounted lights and exposed pipes are not permitted.

D.3.3.1 Gypsum Wallboard: Most ceilings may be constructed of a suspended highdensity, moisture-resistant GWB with an epoxy coating.

D.3.3.2 Suspended Plaster: The use of suspended plaster with an epoxy coating should be considered for areas subject to direct hosing or areas that are constantly wet.

D.3.3.3 Access Panels: Monolithic ceilings, such as suspended GWB or plaster systems, shall be provided with gasketed corrosion-resistant access panels. Panel doors shall also be fitted with a gasket. It is recommended that access panels be minimized in animal housing/holding and procedure rooms so as not to disrupt ongoing research and animal care activities.

D.3.4 Elevator Cabs: Finishes of elevators shall be cleanable and washable. The cab interior is to be totally stainless steel. The elevator cab floor material shall be the same as the floor in the animal facility. The cab interior shall have bumpers, sealed lighting, and sealed buttons.

D.3.5 Windows and Window Treatment: All exterior windows shall be non-operable. All interior windowsills shall be sloped, and all windows shall be caulked and sealed to ensure ease of cleaning and decontamination.

D.3.5.1 Window Treatments: Provide window treatments to meet all functional and aesthetic needs and standards. Light-tight treatments will be provided in all spaces that require room darkening based on program needs. If windows are provided in nonhuman primate areas, the room shall be capable of becoming light-tight. This can be accomplished through the use of adjustable shutters, blackout shades, or blackout panels. Integral devices within the window air space are preferred. No devices may be installed on the animal holding room side of windows or doors. These features are absolutely critical in being able to control the diurnal cycles for research purposes.

D.3.6 Doors and Door Frames: Doors should be sized to easily accommodate passage of cages, racks, and other large mobile equipment. Consider using automatic doors in hightraffic areas. To easily accommodate a variety of personnel and equipment needs, consideration should be given to using two-leaf doorways with differing leaf sizes. In this system, consider leaves sized at 1 100 mm and 765 mm. Where a single leaf is provided, minimum width shall be 1 100 mm. Minimum clear height shall be 2 200 mm high or as required for clear cage passage.

D.3.6.1 Material: Impact damage to doors is a major concern within animal facilities. Doors that are heavily used have a reduced life expectancy and require frequent repair and maintenance. Doors should be equipped with bumper rails. All doors should have kickplates. All doors within the animal facility that are not required to be fire rated, as well as all perimeter exterior doors into any building that houses animals, shall be fiberglassreinforced polyester (FRP) doors. Doors shall conform to the NIH Division 8 Specification Section “Fiberglass Reinforced Polyester (FRP) Doors.”

Key salient features of the FRP doors and frames required for NIH animal facilities include:

• The entire core of the door, including the area within the stiles and rails, shall be completely filled with a minimum 80 kg/m³ density, poured-in-place polyurethane (chlorofluorocarbon-free) with a minimum R-value of 11 to prevent the harborage of insects or vermin.
• Top and bottom rails shall be seamless and flush and constructed as an integral component of the door with no extrusions or capping permitted. Integral reglets to accept facesheets are required to present a flush appearance. Rail caps or other facesheet capture methods are not permitted.
• Door facesheets shall be a minimum of 3.05 mm thick and integrally colored and provide an abuse-resistant engineered surface.
• FRP facesheets shall be tested in accordance with ASTM E-84 and shall have the following Class A ratings: Smoke developed not greater than 310 and flame spread no greater than 15.
• All exposed joints and cracks that occur when two pieces of aluminum join or when aluminum and FRP and aluminum join shall be caulked with a clear silicone to prevent insects or vermin from gaining access to the inner portion of the door cavity.
• All glass (vision panels) and inset louvers shall be factory furnished and installed prior to shipment.
• All intersections between the door or frame surfaces and hardware items shall be caulked with a clear silicone sealant to prevent insects or vermin from gaining access to the inner portion of the door cavity.
• Door frames shall be fitted with solid rubber gasketing material. No bubble weather stripping shall be permitted.
• Premachine doors in accordance with templates from the specified hardware manufacturers and approved hardware schedule. Factory-installed hardware items should be in accordance with the manufacturer’s specifications.
• All surface-mounted hardware shall be sealed around the perimeter of the item with a clear silicone sealant to prevent insects or vermin from gaining access to the inner portion of the door cavity.

D.3.6.2 Door Frames: Door frames shall be completely filled with grout or other inert material to prevent harboring of pests and sealed to surrounding construction.

D.3.6.3 Vision Panels: Vision panels should be provided in the active leaf of double doors and other doors as required by program requirements. Depending on program requirements, vision panels may require light-tight covers.

D.3.7 Door Hardware: Animal facility doors are considered high-use doors. All hardware shall be appropriately specified to withstand this type of use. Light, commercial-grade hardware shall not be specified. All appropriate hardware to meet security, accessibility, and life safety requirements shall be provided. Animal facility door hardware and keying shall comply with requirements outlined in the General Design Guidelines, Section: Architecture.

D.3.7.1 Door Pulls and Hinges for Interior FRP Doors: Specific door pulls shall be provided wherever FRP doors are specified within the interior of the animal facility. This recessed door pull features a “clean room design” with profiles and surfaces that are designed not to hold water from frequent washings. Each door leaf shall be equipped with a continuous, heavy-duty 14 gauge stainless steel hinge with a 6.35 mm stainless steel pin. Geared hinges are not permitted.

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D.4 Structural

D.4.1 Vibration: An analysis of vibration response of the structure shall be made. Consideration shall be given to vibration of floor-framing systems caused by mechanical and electrical equipment such as pumps, chillers, fans, emergency generators, and transformers and other sources such as foot traffic, parking garage traffic, and movement of heavy equipment.

Many animals are extremely sensitive to vibration, which can produce detrimental effects on research. Designers shall take every opportunity to control vibration and to locate vibration sources away from animals and activities sensitive to vibration. Specific vibration recommendations shall be made by an experienced vibration consultant. Steel structures shall not be precluded for use in structural design relative to vibration without analysis.

To control vibration transmitted into the animal facility space, the A/E shall consider the following items during the early design phases:

• The structural system should be relatively stiff so that any transmitted vibration occurs at high frequencies. Vibrations occurring at higher frequencies are more easily dampened with instrumentation vibration-dampening systems and isolation tables than vibrations occurring at lower frequencies.
• The structural system should have relatively short column spacing.
• Animal facility spaces should be located away from sources of vibration.
• Animal facilities should be located on grade-supported slabs. This not only reduces vibration concerns but also more easily accommodates pits required for cage and rack processing, and the risk of water leakage to lower levels is eliminated.
• On framed floors, corridors and animal facility spaces should not be combined in the same structural bay.

D.4.2 Module/Bay Size: The dimension of the structural bay, both vertical and horizontal, shall be carefully evaluated with respect to the functional requirements of animal facility spaces, the primary building module, mechanical distribution, and future expansion plans. The horizontal dimension of the structural bay shall be a multiple of the planning module or primary building module dimension for maximum flexibility and to allow uniform points of
connection for animal facility services.

Columns shall not fall within the animal facility planning module or building module to prevent interference with animal facility space planning and cause inefficient use of animal facility space. Close coordination between structural and mechanical disciplines is critical to minimize interference of piping and ventilating systems with the structural framing.

D.4.3 Floor Slab Depressions: Floor depressions and/or topping slabs will be evaluated for use in special-finish areas, wet areas, or areas exposed to materials that may deteriorate the structural floor slab. Floor depressions shall be reviewed for equipment requirements to allow for ease of movement of equipment. Floor slabs shall slope to accommodate drainage, and pits shall be provided in cagewash areas. Suitable protection of the concrete and reinforcing shall be considered in high-temperature cagewash areas.

D.4.4 Equipment Pathway: The potential routing or pathway for the addition or relocation of heavy equipment shall be reviewed and identified during the design phase.

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D.5 Heating, Ventilation, and Air Conditioning (HVAC)

HVAC systems shall meet the requirements published in the Guide. Temperature, humidity, and air change rate shall be carefully controlled and monitored on a continuous basis. Systems shall have adequate ventilation capacity to control fumes, odors, and airborne contaminants and offset the heat load of lab animals.

HVAC systems shall be both reliable and redundant and operate without interruption. HVAC systems shall be designed to maintain relative pressure differentials between spaces and shall be efficient to operate, both in terms of energy consumption and from a maintenance perspective. Federal Energy Standards, to the extent possible, shall be achieved. Studies shall be conducted during the design phase to determine the feasibility of utilizing heatrecovery systems in animal facility buildings.

Principal design guidelines include control of contamination, prevention of crosscontamination, temperature and humidity control, energy conservation, and reliable operation. Refer to General Design Guidelines, Section: Mechanical, for systems design, basis of design report, and energy conservation compliance requirements.

D.5.1 Outdoor Design Conditions for the NIH, Bethesda: For facilities whose purpose is animal research and for HVAC systems requiring 100 percent outside air, outdoor design conditions shall be as follows:

Table D.5.1.a Outdoor Design Conditions for the NIH, Bethesda (Facilities With 100 Percent Outside Air)

                            Latitude, 39 N; daily temperature range, -8 °C.

For all other facilities such as office buildings, administrative facilities, and noncritical HVAC systems not requiring 100 percent outdoor air, the values recommended by the current American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Handbook of Fundamentals shall conform to the following:

Table D.5.1.b Outdoor Design Conditions for the NIH, Bethesda (Facilities Not Requiring 100 Percent Outside Air)

The design wet-bulb temperature for sizing cooling towers shall be 1° higher than the ASHRAE 1 percent outdoor design wet-bulb temperature. All outdoor air-cooled condensing equipment shall be designed and selected on the basis of a 41 °C ambient temperature.

D.5.2 Indoor Design Conditions: The following indoor design conditions shall be used in the design of the animal facilities. Animal holding areas shall be maintained at the design conditions at all times. Design conditions shall be satisfied under all load conditions among the various holding areas.

Table D.5.2 Indoor Design Conditions

D.5.2.1 Animal Housing:

Table D.5.2.1 Animal Species Design Conditions

*Special HVAC considerations for rabbits: Rabbits require lower temperatures than most ther species. The ability to control temperature and maintain an appropriate humidity level is important for their breeding and well-being. The appropriate temperature range for rabbits is 16 to 20 °C.

Ideally, every animal holding room shall be capable of housing all species to be housed within the facility. The HVAC system shall also be capable of maintaining the full range of requirements for all anticipated animal populations. The temperature range required to accommodate most commonly used research animals is 18 to 29 °C controlled to ±2 °C. The ranges do not represent acceptable fluctuation ranges. The humidity shall be between 30 and 70 percent and normally controlled to 50 ± 5 percent. These ranges can be narrowed when the anticipated species have similar requirements.

Some laboratories within the animal facility conduct special research requiring unique temperature and humidity ranges and control. These special cases shall be evaluated and provided for on a case-by-case basis. The HVAC system shall be designed to accommodate these unique conditions as they occur.

D.5.3 Air Quality: HVAC systems for animal facilities shall be independent from other building HVAC systems. These systems shall maintain a safe and comfortable environment for animals, be adaptable, and be capable of maintaining environmental conditions in any of the holding rooms for any of the species anticipated to be housed in the facility. Since most animal studies are of long duration, they shall be performed under consistent conditions in order to achieve repeatable results. Thus, failure of the HVAC system is unacceptable. Central HVAC systems thus should be provided with multiple air-handling units and exhaust fans to provide redundancy and improve reliability.
Some rooms may be designated as “hooded rack” rooms having a housing chamber with sash fronts similar to a walk-in fume hood or individual air recycle systems of the laminarflow type. Unit directional flow, laminar-flow systems for any of the rooms may also be required.

With regard to ventilation, the following objectives should be considered: the elimination of drafts that could adversely affect animal health; monitoring, maintaining, and recording consistent temperature and humidity conditions in individual rooms; and controlling the airborne animal hair and particulate count. The minimum ventilation rate for animal housing and treatment facilities shall be in accordance with ASHRAE Applications Handbook, Chapter 21, and the Guide. Recirculation of air in an animal facility is prohibited. The air conditioning flow rate for an animal room shall be determined on the basis of the following factors:

• Desired animal microenvironment
• Species of animal(s) and its (their) population(s)
• Required minimum ventilation rate
• Internal loads within animal room
• Recommended ambient temperature and humidity
• Heat gain by the animals

The A/E shall consider additional factors, such as the method of animal cage ventilation, operational use of a fume hood or a BSC during procedures involving animal cage cleaning and animal examinations, airborne contaminants, and institutional animal care standards, as applicable to animal facilities.

In addition to the prefiltration normally used, additional filtration is generally provided with efficiencies ranging from 95 to 99.99 percent (HEPA). This final filtration is to protect against particulate and other contaminants, which the air-handling equipment itself can generate. The A/E shall review the project’s Program of Requirements to establish specific filtration criteria.

D.5.4 Air Distribution: Animal facilities shall be designed with special attention to air quality, acoustics, airflow quantities, diffusion characteristics, means of delivery, delivery temperature, air velocity, and air distribution.

• Distribution shall prevent cross-contamination between individual spaces, and air shall flow from areas of least to areas of higher contamination potential (i.e., from “clean” to “dirty” areas).
• Air supply terminals shall be located at ceiling level or close to ceiling level if located on sidewalls. Air distribution and diffusion devices shall be selected to minimize temperature differentials in the space. The maximum air velocities in the occupied zone shall not exceed 0.25 m/s at an elevation of 1.8 m.
• In the cagewash facility, the “dirty,” “clean,” and cagewash equipment, including associated mechanical supporting equipment areas, shall be physically separated from each other, including equipment pits. Canopy exhaust hoods shall be installed for heatgenerating cagewash equipment in both the “dirty” and the “clean” sides of the facility.

D.5.5 Relative Pressurization: Animal facility spaces shall be protected against contamination from outside sources, including particulates brought in from the outside in the HVAC airstream. Generally, the animal facility shall remain at a negative air pressure relative to clean corridors and other non-animal facility spaces. Relative pressurization inside the animal facility is a series of complex relationships. Some of these relationships may change as research and animal populations change. The HVAC system shall be capable of maintaining these relative pressure relationships and capable of adapting as facility utilization changes.

“Clean” areas of the facility—including the “clean” side of cage and rack washing, the “clean” corridor system, and bedding dispensing, diet, and preparation areas—shall be positive relative to animal holding areas or “dirty” areas.

The relative pressure in animal housing areas is generally negative relative to “clean” areas and positive relative to service corridor and “dirty” areas.

“Dirty” areas such as the service corridor, the “dirty” side of the cage and rack washing area, and decontamination and waste holding areas shall be maintained at a negative pressure relative to the animal rooms.

Some areas have special pressurization requirements and shall be addressed individually. Animal holding areas for transgenic or immunosuppressed populations shall be maintained at a positive pressure and may require special filtration of supply air.

Potentially infectious populations shall be maintained at a negative pressure to prevent contagion from migrating to other populations. Depending on the nature of the infectious agents involved in the research, these areas may be required to meet the design criteria for biohazard containment facilities. To maintain these special conditions, anterooms or microisolator housing units may be required.

The pressure relationships for animal care areas—including treatment rooms, procedure rooms, necropsy rooms, and surgical areas—require investigation by the design team with the facility user to determine project-specific requirements. The HVAC system shall be adaptable so that pressure relationships can be modified as required over the life of the facility.

The “dirty” elevator shaft is to have air pressure negative to all surrounding areas.

D.5.6 Ventilation: The ventilation requirements for all animal holding and procedure areas at the NIH are discussed in detail in the General Design Guidelines, Section: Mechanical. Small-animal static cage/rack systems require a minimum of 15 air changes per hour, whereas ventilated cage rack systems require a minimum of 10 air changes per hour. On average, large-animal holding areas require a minimum of 15 air changes per hour.

Exhaust from animal rooms shall be discharged to the outside with no recirculation of air to other rooms. For protection of personnel and to minimize the potential for crosscontamination of animals, the direction of airflow shall be inward to the animal rooms at all times. Where protection of the animals from possible contamination is important, consideration should be given to providing ventilated airlocks for the animal rooms. The use of filtered isolation cages may also be considered. A/Es should consult with animal facility personnel with regard to the specific requirements for protection of animals.

D.5.7 Heating and Cooling Load Calculations: Complete design load calculations and a vapor drive study shall be prepared for each space within a design program and presented in a format similar to that outlined in the latest ASHRAE Handbook of Fundamentals. Heating and cooling load calculations are required for all projects to facilitate review and provide a reference for system modifications. Individual room calculations shall be generated and summarized on a system basis and presented with a block load to define the peak system load. Load summary sheets shall indicate individual rooms with area, design air quantity, L/s per m2, air changes per hour, and corresponding return or exhaust air quantity. Calculations shall include but not be limited to indoor and outdoor design parameters, heat gains and heat losses, supply and exhaust requirements for central systems and for each area of the facility, humidification and dehumidification requirements, and heat recovery. As a reference, calculations for assessing heating and cooling loads may include but are not limited to the elements in the following table:

Table D.5.7 Load Calculation Considerations

All heating and cooling load calculations shall include a predetermined safety factor to compensate for future flexibility, infiltration, and air leakage. Safety factors shall be clearly defined in the basis of design report.

D.5.8 Building Solar and Conduction Loads: The design engineer shall provide a thorough review of all building construction components to accurately calculate the resultant R-values and U-values for the various construction conditions. Calculations shall include a sketch of the construction conditions and include a written description of where the conditions exist. Component R-values used shall be referenced as to their source and where possible tied to project specification. R-values and U-values, shading coefficients, vapor transmission values, transmittance, doors, windows, and skylights shall be selected by the A/E and accurately defined in the project specification.

D.5.9 Lighting Loads: The HVAC system shall provide as a minimum capacity for the following heat loads generated by room and task lighting:

Table D.5.9 Lighting Loads

D.5.10 Occupant Loads: One person per 100 nm² of animal facility space.

D.5.11 Animal Room Heat Loads: ASHRAE data concerning animal heat loads and NIH estimates concerning animal room occupancy shall be used for system design. The following chart illustrates the heat generated by some of the laboratory animal species:

Table D.5.11 Animal Heat Loads by Species

D.5.11.1 Animal Density: A typical 3 x 7 m animal holding module will have the following species density:

Table D.5.11.1 Animal Density by Species

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D.6 Plumbing

Types of plumbing systems in the animal facility may include wash systems, waste drainage systems, animal drinking water systems, and medical gas systems. Plumbing systems specifically installed for animal support require close review with an animal care specialist to determine the exact feature designs.

Guidelines for animal facility plumbing system design shall carefully minimize the potential for accumulating dirt and providing pest harborage and access to animal care areas and ensure that all pipes, mounting brackets, supports, and so forth are caulked and sealed during installation. Some general criteria that should apply include minimizing any exposed piping inside animal rooms, installing piping with standoff support to aid in proper cleaning, avoiding being carefully sealed, and evaluating pipe materials that do not use toxicreleasing compounds during manufacturing. Careful consideration shall be given to drainage facilities since waste lines frequently become clogged, and buried waste pipe should be one size larger than required for normal use.

D.6.1 Waste: Large quantities of liquid waste leave the animal facility through the sewer systems. As such, the system shall be adequately sized, particularly if it is recommended for animal rooms. Floor or trench drains with an automatic water system for maintenance should be considered in large-animal rooms. Most small-animal holding rooms do not require a drain or hose bib. A percentage of holding rooms in the facility may be designed with a drain to accommodate fish tanks, rodent swim tanks, or farm animals.

Disposal of solid waste in the form of bedding, paper, feces, animal carcasses, and other miscellaneous wastes shall also be carefully considered. Bedding can be disposed of by a mechanical slurry system contained in a cagewash. This procedure reduces labor and the volume of solid waste.

D.6.1.1 Floor Drains: Floor drains are not essential in all animal rooms. The A/E should review the need for floor drains with animal facility and safety personnel. Where necessary, floor drains shall be capable of being capped off and sealed when not in use.

D.6.2 Water Supply: Incoming mains will serve both domestic (potable) and industrial (nonpotable) water systems. Backflow preventers on the industrial water system will be used to protect the potable water system. Duplex water pumps should be used if required to maintain a minimum water pressure of 240 kPa at the highest outlet (fixture). A pressurereducing valve should be provided if required to limit maximum water pressure at 450 kPa.
All animal facility water fittings shall be equipped with vacuum breakers in accordance with General Design Guidelines, Section: Plumbing.

D.6.2.1 Potable Water: Potable water will be connected to all non-animal research plumbing fixtures, emergency showers, and eye washers. Potable hot water will be recirculated. The required temperature for potable hot water shall be 26.3 °C.

D.6.2.2 Industrial Cold and Hot Water: Industrial water serving process equipment and laboratory space in the animal facility shall be isolated from the potable water supply. Industrial water fed from the incoming domestic supply shall be separated through a backflow preventer. The industrial hot water system may be generated with heat exchangers and be recirculated. The required temperature for industrial hot water shall be in accordance with General Design Guidelines, Section: Plumbing.

D.6.2.3 Animal Watering System: The designer should investigate the animal watering requirements for the facility. The animal watering system shall be separated from the domestic water supply with a backflow preventer. The quality of water to be utilized in the animal watering system shall be determined by the users and animal care staff. The type and quality of the water depend on the type of animal population, the type of research being conducted, and the quality of the domestic water supply. The domestic water supply may be adequate for many types of animals and research. However, in other applications, treated water may be required. Treatment may include reverse osmosis (RO), deionization, or chemical injection. Specific requirements for the zoning, number of water connections per room, control, injection capability, and flushing shall be verified by the users. When automated watering systems are used, a manifold for flushing hoses is required in the cage and rack-washing area.

Many NIH animal facilities use a combination of bottle and automatic watering systems. Accommodation for automatic watering at a future time or in a portion of the facility should be considered. The designer should also investigate the applicability of specialized water processing for the facility (i.e., RO, ultraviolet [UV] sterilized, chlorination, acidification, etc.). In addition, the impact of specialized water on the proposed bottle fillers, proportioners, and distribution piping shall be considered.

D.6.2.4 Special Plumbing Considerations for Aquatics: Slight variations in water salinity or pH can kill the animals. Piping should be of an inert material. Metal piping, especially copper and zinc piping, should be avoided since it leaches chemicals that are toxic to most aquatic species. Floor drains should be designed to minimize the retention of organic matter (no recesses, inaccessible lips, etc.) and be easily accessible for cleaning and pest management inspection.

If a saline environment is required, the equipment shall include a supply-mixing tank upstream from the holding tanks. In a saline environment, all materials shall be corrosion resistant.

D.6.3 Medical Gas for Animal Procedures: Medical gas systems for animal procedures may consist of a cylinder supply system without reserve supply or bulk supply without reserve supply. Systems will consist of a primary source and a secondary supply that will operate automatically to supply the pipeline as the primary source becomes exhausted. The secondary supply will consist of at least 3 days’ average supply unless the local resupply situation dictates a greater secondary supply amount. An alarm panel to monitor line pressures and the status of supply equipment shall be provided. Monitoring shall be done via pressures and switches and contacts located downstream of the manifold. All systems will comply with the latest edition of NFPA 50, 56F, and 99. The following medical gases will be provided for the appropriate functional areas:

Table D.6.3 Medical Gas Terminals for Animal Procedures

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D.7 Electrical

D.7.1 Normal Power: The following load figures in watts per square meter (W/m²) shall be used in sizing the overall building service. These figures are connected load and should be used in the early design stages. Actual design loads shall be used in the later part of the design. The range provided allows for varying intensity of usage. The mechanical loads do not include chilled water or steam generation, which are produced centrally on the NIH campus. The A/E shall use sound judgment in applying these numbers.

Table D.7.1 Normal Power Load Figures

Conduits in animal facilities shall be concealed. Surface-mounted conduits in washdown areas shall be intermediate metallic conduit (IMC) or rigid galvanized steel with threaded couplings. Conduits in animal facility areas shall be sealed with conduit sealer such as Duxseal at each device/junction box. Surface metal boxes shall be cast metal. Conduits entering or leaving device boxes, junction boxes, pull boxes, and so forth shall be sealed at each box with a non-hardening sealant such as Duxseal. An alternative is to use seal-off fittings in conduits penetrating animal facility walls. A potting compound shall be poured into the fitting after the wires are installed. Surface metal raceway with snap-on covers shall not be used in an animal facility because of the requirements for washdown cleaning.

Operating rooms associated with animal facilities shall have isolated power panels with ungrounded secondary and line isolation monitors. Branch circuits in operating rooms shall have type XHHW insulation and #10 AWG ground conductors. Isolated power branch circuits shall have conductors with orange and brown XHHW insulation to reduce leakage current.

D.7.2 Emergency Power: The following load figures in watts per square meter (W/m²) shall be used in sizing the generator. These figures are connected load and should be used in the early design stages. Actual design loads shall be used in the later part of the design. The range provided is to allow for varying intensity of usage. The A/E shall use sound judgment in applying these numbers.

Table D.7.2 Emergency Power Load Figures

* Supply and exhaust fans for animal holding
** Minimum: one elevator per bank of elevators

The following loads are required to be connected to emergency power. These loads are in addition to any emergency loads that are required by code:

• Operating room
• Animal ventilation fans
• Ventilated animal cages and cage systems
• CCTV cameras and equipment, security system
• Switch-controlled minimal lighting in animal holding rooms

D.7.3 Lighting: The lighting levels listed below in lux shall be used for design purposes. The values listed are average maintained footcandle levels using a total maintenance factor of 75 percent. The numbers listed are target values and shall be adjusted to meet the research requirements.

Table D.7.3 Lighting Levels

Areas not identified above shall use the Illuminating Engineering Society of North America (IESNA) Lighting Handbook for recommended values. Lighting in animal facilities shall be dimmable and shall have time-of-day automatic control where required for controlled environment studies. Industrial fluorescent lighting fixtures shall have a wire guard or plastic sleeves over the lamps.

D.7.3.1 Lighting Controls: All small-animal holding rooms should have individual light controls and light timers. Ideally, holding rooms should have individual temperature and humidity control as well.

D.7.3.1.1 Isolation Cubicle Lighting: Isolation cubicle lighting should be connected to the central lighting control system. Access to a manual override shall be restricted through the use of a key or card-key system.

D.7.4 Security: Animal facilities require strict access control. A card system exists on campus for building access. The Division of Security Operations (DSO) shall be notified during the early stage of design for card access approval.

D.7.5 Communications: Some racking systems are now designed with dynamic LAN line connections. Consideration shall be given to the requirement of LAN connections within the animal holding room.

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D.8 General Health and Safety

Additional general health and safety regulations, codes, and standards that are required references for this section of NIH Design Policy and Guidelines are located in the Appendix.

The NIH, through the Division of Safety, has developed a comprehensive Occupational Safety and Health program to protect the safety and health of all employees on the campus. This includes the occupational work setting found in laboratories, clinical settings, animalhandling activities, and mechanical support services.

Safety and health regulations and guidelines require the use of engineering controls for worker protection, wherever possible, to minimize the potential for occupational exposure to hazards in the workplace. To be most effective, engineering controls for protecting occupational safety and health shall be designed into facilities for both new construction and renovated space. This proactive approach can minimize numerous common potential health and safety concerns in animal facilities. These health and safety guidelines are to be incorporated, as appropriate, in facility-specific construction documents by the A/E to ensure that health and safety protection is engineered into the design of any new or renovated facility.

While many of the requirements for health and safety engineering are incorporated in these Guidelines, it is impossible to cover all possible concerns. The A/E firm should, whenever possible, have a health and safety specialist on staff and shall always consult with Division of Safety personnel with regard to specific health and safety engineering requirements in the design of new construction and renovation projects.

D.8.1 Physical Hazards: Animal holding areas shall be designed with employee movement requirements in mind. Specifications for animal facility equipment should include a requirement that, whenever possible, sharp edges and other pro-tuberances that may cause injury to either personnel or animals should be avoided. The location, height, weight, and ergonomic problems of wall-mounted cages shall be considered in the design in order to minimize employee hazards associated with lifting and removing these large objects.

Because of the frequent washing/wetting down of surfaces, floor areas should be slightly sloped to the drain to reduce pooling of water and the probability of slips and falls. Because of the potential for wet environmental surfaces in the animal facility, all electrical systems and apparatus shall be connected to a ground fault circuit interrupter (GFCI) to prevent electrical shock in accordance with 29 CFR 1910, Subpart S, requirements. See General Design Guidelines, Section: Electrical, for the discussion on shunt trip breakers and GFCIs.

D.8.2 Emergency Safety Equipment: Where potentially hazardous chemicals and cleaners are in use (e.g., cagewashing areas, etc.), eyewash stations and safety showers are required. Eyewash stations should be available within 22 m of the site of chemical usage. In addition, any room equipped with a chemical fume hood shall have an eyewash station and safety shower. See General Design Guidelines, Section: Plumbing, for requirements.

D.8.3 Gas Cylinders: Where appropriate, gas cylinders should be placed outside the animal area, with piping and wall valves to access the gas(es). Therefore, an area to place, secure, access, and remove the cylinders shall be provided. Anesthesia gases for surgical purposes may be required at the site of use. The A/E should consult with animal facility personnel to determine the preference of the user.

D.8.4 Waste Storage: The waste storage area shall be located on the “dirty” side of the facility. This area shall be sufficiently large for the storage of waste materials generated in the facility. This location should be near exit doors and should provide sufficient room to facilitate movement of waste containers/carts in a safe manner, with minimal ergonomic stress. The waste storage area shall be caulked and sealed to minimize pest harborage and promote proper cleaning.

D.8.5 Cagewashers: The cagewash facility shall be designed to minimize the noise produced from the equipment and operation carried out in the area. Noise emission at any one location should be less than 85 dB. New cagewashers’ operating noise emissions should not exceed 85 dB. Cagewashers shall have an integral acid neutralizing tank to neutralize acid used during the purge cycle.

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D.9 Biosafety

Additional biological safety regulations, codes, and standards that are required references for biosafety design are located in the Appendix.

Major biosafety concerns for animal facilities include ventilation for animal welfare, sanitation, and containment of animal dander and odors and infectious agents. “Clean”/”dirty” corridor designs are recommended with directional airflow and minimal pressure differentials from “clean” to “dirty” areas.

D.9.1 Biosafety Level 3 Facilities: ABSL-3 animal facilities shall be designed for the containment of indigenous or exotic agents, which have potential for respiratory transmission, may cause serious and potentially lethal infections in personnel, and can be spread to the community through release to the environment. The following requirements shall be met in the design of ABSL-3 containment facilities.

D.9.1.1 Restricted Access: ABSL-3 animal facilities shall be separated from other animal facilities and work areas by passage through two sets of “self-closing” doors. A ventilated airlock shall be designed to separate the common corridor(s) from the ABSL-3 containment animal facility.

The purpose of a ABSL-3 animal facility is to ensure containment of agents used in the facility. It is recommended that airlock doors be interlocked to prevent simul-taneous opening of doors between the outside corridor and containment areas. Interlocks, when present, should be provided with a manual override for use in case of emergency. Final determination on the design of airlocks for these facilities should be made in consultation with safety personnel.

D.9.1.2 Windows: Animal facilities should be designed without windows. However, windows, where present, shall be designed not to open. All windowsills shall be slanted, and seams around windows shall be sealed as with other seams in the laboratory to ensure ease of cleaning and decontamination.

D.9.1.3 Interior Surfaces: Interior surfaces of walls, floors, and ceilings shall be water resistant (i.e., epoxy paint, caulking, etc.), gas tight, and easily cleanable.

D.9.1.4 Integrity of ABSL-3 Space: All electrical and plumbing conduits and supply and exhaust ducts shall be sealed at the point of penetration into the facility to ensure containment and the capability for gas decontamination. All penetrations in walls, floors, and ceilings shall be sealed (with a smooth finish) to facilitate decontamination and cleaning. All joints between fixed cabinetry (e.g., shelves, cabinets, plumbing fixtures, etc.) and the floor or wall shall be smooth-coved and sealed to ensure maximum cleanability.

In all new construction, all access to critical mechanical equipment (e.g., ventilation ducts, fans, piping, etc.) shall be provided outside the containment facility. No compromise of the integrity of the containment of the ABSL-3 animal facility is allowed.

When retrofitting existing ABSL-2 animal space to ABSL-3 containment, it may not be possible to keep access to critical mechanical equipment outside the space. In these cases, an access panel shall be supplied inside the laboratory to allow access to such mechanical equipment. The access panel shall be hinged with a piano-type hinge and gasketed with gas-tight gaskets to ensure an appropriate seal for both containment and decontamination procedures.

D.9.1.5 Hand-Washing Sinks: A sink for hand washing shall be located near the exit door of each ABSL-3 suite and not in the airlock. Sink faucets shall be foot, elbow, or automatically operated.

D.9.1.6 HVAC/Exhaust: Ventilation shall be single-pass air, and all ABSL-3 space shall be kept negative with respect to outside corridors and laboratories. Exhaust ducts shall be under negative pressure until discharged outside the building or passed through a HEPA filter. While HEPA filtration of room exhaust from ABSL-3 animal facilities is not always necessary, an evaluation of the need for specific filtration should be performed during the initial planning and design stages of the project. User groups and personnel of the NIH Division of Safety shall be consulted. Safety personnel will determine the need for such filtration.

The exhaust from an autoclave contains a significant amount of moisture. Filtration of this exhaust, when necessary, shall be through a moisture-resistant (hydrophobic) filter such as a Pall 0.2 micron filter or the equivalent.

D.9.1.7 Vacuum Systems: Vacuum systems in ABSL-3 animal facilities shall be protected by filtration. See requirements in General Design Guidelines, Section: Plumbing, Vacuum Systems.

D.9.1.8 Alarms: ABSL-3 facilities shall be alarmed to indicate a failure to maintain a negative pressure differential from a noncontaminated area to potentially contaminated areas. Both visual (gauges) and audible alarms are necessary. All alarm systems shall be validated prior to occupancy of the containment space by research personnel.

D.9.1.9 Biological Safety Cabinets/Containment Equipment: Appropriate biological safety cabinets and other containment equipment shall be provided as necessary for the work to be performed. The determination of appropriate equipment needs should be made in consultation with user groups and NIH Division of Safety personnel during the design phase of the project.

D.9.1.10 Autoclaves: An autoclave for decontamination of waste from the ABSL-3 animal rooms shall be available in the facility, preferably within the ABSL-3 suite. See paragraph D.2.4 for planning requirements for an autoclave.

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D.10 Radiation Safety

Additional radiation safety regulations, codes, and standards that are required references for radiation safety design are located in the Appendix.

Work performed at the NIH animal facilities involves the potential for occupational exposure to radioactive materials and other sources of ionizing and non-ionizing radiation. Although the procedures identified as good radiation safety (health physics) practices and techniques are essential to minimize potential exposure to radiation, the security, containment, and shielding of this material and equipment through the use of good facility design are extremely important elements. In addition to the protection of occupationally exposed workers, the NIH Division of Safety, Radiation Safety Branch, must ensure that the general public and surrounding environs are also provided with an adequate and similar degree of protection.

The intent of this section is to provide the A/Es with a working knowledge of the facility design parameters required for the construction of facilities, which shall provide for the control and containment of radiation hazards.

Not all sources of ionizing radiation are covered by Nuclear Regulatory Commission (NRC) licensing. These nonlicensed sources are, however, controlled by regulations issued by the NIH Radiation Safety Committee upon recommendation by the Radiation Safety Officer. Nonlicensed sources include x-ray machines, high-voltage accelerators, electron microscopes, and radioactive materials from sources other than reactor by-products.

D.10.1 Background: The NIH Radiation Safety Guide provides guidance and technical information concerning the use of radioactive materials as well as policies and procedures for radiation-producing machines and areas. Radiation safety control, containment, and shielding design and animal facility practices have been developed to minimize the potential for radiation exposure to workers as well as radiation release to the environment.

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D.11 Animal Facility Fire Protection

This fire protection section includes specific requirements for animal facilities. The general fire protection requirements are found in General Design Guidelines, Section: Fire Protection.

D.11.1 Fire Suppression: In areas with washdown ceilings, provide gasketed concealed heads. In areas that also have a pressure differential at the ceiling, which can affect the operation characteristics of the concealed heads, the gasketed concealed heads shall be specifically listed for use in ceilings with pressure differentials.

D.11.2 Fire Alarm: A fire alarm voice communication system shall be provided in the animal holding/procedure areas. Upon an alarm, the fire alarm speakers are to sound a “slop whoop” signal, at 90 to 110 dB, for one cycle (4.1 seconds), followed by a repeated voice evacuation message. The voice message shall continue until the fire alarm control panel is reset or the “alarm silence” switch is activated. See General Design Guidelines, Section: Fire Protection, for additional fire alarm requirements.

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D.12 Animal Facility Pest Management

For general design considerations related to pest management, see General Design Guidelines, Section: Pest Management. Consideration of pest management shall be given to any function, finish, or detail contributing to pest infestation and harborage in or around the building. Design features shall promote cleaning and maintenance while minimizing pest ingress and harborage. Floor penetrations and void areas shall be minimized and completely sealed. The A/E shall ensure that areas of pest ingress such as doors, windows, loading docks, and so on are fitted with appropriate pest-exclusion devices. Consideration shall be given to designs that minimize pest harborage and promote proper cleaning. Examples of harborages are inaccessible voids behind and under equipment and casework, unsealed cracks or joints between pieces of equipment or finish materials, or the use of unsealed foam or fiberglass insulation on pipes and equipment. The NIH Division of Safety, Integrated Pest Management Unit, shall be consulted to review and approve all plans for new construction or renovation of old space and to obtain additional program-specific caulking and sealing information.