The California National Primate Research Center (CNPRC) is one of the eight National Primate Research Centers supported by the National Center for Research Resources of the National Institutes of Health. The CNPRC provides specialized research facilities, non-human primate resources, scientific and professional staff, equipment and technical expertise in support of primate-related research. The CNPRC currently uses kerosene heaters to provide supplement heat to outdoor field corrals. These units are inefficient and we are unable to remain compliant with air pollution standards. This proposal seeks funds to replace these units with gas-fired heaters to provide improved supplemental heating capabilities, as required by USDA standards for animals housed outdoors, and to provide a safer and environmental alternative to the existing kerosene heaters.