title: [Observation on the air-borne bacteria and ammonia (NS3) gas in laboratory animal facility with rotary heat exchanger].
abstract: The number of air-borne bacteria in air ducts and barrierred laboratory animal rooms with the so-called econovent rotary heat exchanger, were checked monthly during a year by the pin-hole sumpler method for air ducts and Koch method for animal rooms. Also, concentration of ammonia was checked with the same samples by gas impinger. No significantly difference in number of air-borne bacteria was seen between before and after passing the econovent. Those passing through HEPA filter was not detected. There were more air-borne bacteria in animal rooms, outside locker room and shower room than in the corridor, utensil storage, inside locker room and pass box. No ammonia were detected in the outdoor, but exhaust air duct after passing the econovent contained very small amount of ammonia. On the other hand, high concentration of ammonia were preserved in the supplying air duct, exhaust air duct and mice and rats rooms, about 86% of ammonia in exhaust air duct returned back into the supplying air duct. No influences on reproduction in mice and rats were recognized.
mesh_terms: D000388:Air / Q000032:analysis*; D000389:Air Conditioning; D000391:Air Microbiology; D000641:Ammonia / Q000032:analysis*; D000818:Animals; D000830:Animals, Laboratory; D001419:Bacteria / Q000302:isolation & purification*; D006799:Housing, Animal
chemical_list: D000641:Ammonia