Research Animal Holding Facility (RAHF)

The Research Animal Holding Facility (RAHF) is a general use, contained animal habitat within the STS Spacelab capable of holding up to 24 adult rats (350 gm) in pairs or four adult squirrel monkeys (1 kg) within separate cages. The monkey and rat versions of the RAHF differ only in the design of the cage module to accommodate different animal sizes; otherwise all subsystems are identical.

Environmental Control System (ECS)*: The ECS is mounted on the back of each cage module to circulate conditioned air through the cages to control temperature and humidity, and to remove CO₂ and replenish O₂ by exchange of air with the Spacelab.

Feeding/Watering Systems*: Rodent food bars and primate pellets are supplied automatically on an ad libitum basis. Individual water lixits are positioned within each rodent and primate cage and dispense water ad libitum.

Primate Cage Modules*: A squirrel primate cage module system supports four squirrel monkey cages.

Rodent Cage Modules*: A rodent cage module supports twelve cage inserts, each containing two rats, separated by an internal divider for a total of 24.

Activity Monitors: Each rodent and primate cage compartment contains activity monitors that record general animal movement (one for each rodent cage, two for each primate). It consists of an infrared light source (920 nm beam) and sensor mounted on the right side of the cage and reflector tape mounted on the left side of the cage. When the animal breaks the light beam and therefore the circuit, a counter is electronically advanced one pulse. The counter reading is recorded by the RAHF data system for transmission to the ground in realtime or near realtime.

Data System: The system collects three data types: 1) analog data (temperature, humidity, water pressure, air flow); 2) event or discrete data (heating, cooling, lighting, water leakage); and 3) pulse-code modulated data (food, water, activity). The data system collects selected data and sends it to the front panel of the RAHF to an umbilical for monitoring selected RAHF data prior to launch, and to a recorder during liftoff and landing; it formats data through a Remote Acquisition Unit (RAU) for processing by the onboard experiment computer utilizing a series of data display formats.

Lighting System: Cage illumination provides a day/night cycle capability. The baseline system uses two long-life, incandescent lamps for each rat cage and one per mouse cage (not yet flown). The lamps are located in the air plenum above the cages. Each lamp provides 2.1 lumens and approximately 5 foot candles of light at the cage floor. Each of six tiers of drawers can be independently controlled for lighting through a manual or timed operation. The timed operation is performed by selection and setting of "on" and "off" time dials on the front of the RAHF rack.

•Callahan, P.X., et al.: Ames Research Center Life Sciences Payload Project for Spacelab Mission 3. SAE Technical Paper Series 831094, July 1983.

•Hogan, R.P. and B.P. Dalton: Performance of the Research Animal Holding Facility (RAHF) and General Purpose Work Station (GPWS) and other Hardware in the Microgravity Environment. SAE Technical Paper Series 911567, July 1991.

•Ames Research Center, Life Sciences Payload, Spacelab-3, 60 Day Report. P.X. Callahan, ed., NASA Ames Research Center, Space Life Sciences Payload Office, April 1985.