Consideration should be given to the types and amount of electronics and other equipment used to ensure that the HVAC system can accommodate the associated heat loads. Airlocks and air pressure differentials between spaces can provide olfactory segregation of species and activities and thus reduce the risk of altered behavioral responses (ASHRAE 2007c).
When possible, testing equipment should be designed in such a way as to allow surface disinfection between studies. Components that cannot be cleaned or disinfected, such as computers and recording equipment, should be located in areas where contact with animals is unlikely and should be covered when not in use (the use of computer keyboard covers may also be beneficial). Provision of sufficient space for storage of behavioral apparatus and equipment should also be considered. As transportation to and from the testing area may alter behavioral responses, consideration should be given to providing housing areas contiguous with those used for testing; if such areas are provided, they should meet the requirements specified in the Guide.
Many of the construction features described above are applicable to those for aquatic species, but particular consideration should be given to the housing systems used and the methods for maintaining the aquatic environment.
The complexity of the life support system depends on the species housed and the size, type, and number of tanks and animals supported. All systems require a water source, which may require prior treatment (e.g., ultraviolet sterilization and particulate, carbon, and ultrafiltration). Holding areas for aquatic species should be provided with drains of a suitable size and number to accommodate water released during system operation and maintenance or as a result of life support system or tank failure. Drains should not permit passage of animals or hazardous materials into the sanitary system without appropriate treatment.
Materials used for floors, walls, and ceilings should be impervious to water while floors should be slip resistant and able to withstand the loads inherent with large quantities of water. Electrical receptacles or circuits should be ground-fault interrupted to prevent electrocution of personnel and animals. Doors and frames, supply diffusers, exhaust registers, lighting fixtures, HVAC ducts and components (exposed to high levels of moisture or corrosives), and other metallic elements should be made of moisture- and corrosion-resistant materials. Housing systems, life support system components, and plumbing used to distribute water after treatment, including adhesives to connect components, should be constructed of materials that are nontoxic and biologically inert. If the macroenvironmental/room HVAC system is used as the primary method for tempering the aquatic environment, sufficient ventila-