Air quality monitoring in a neonatal intensive care unit.

Air sampling in health care facilities, especially in specialcare areas such as neonatal intensiv? care units (NICUs), should be done on a periodic basis ln Order to determine indoor air quality, efficacy of dust control measures, or airhandling system performance. (The draft guideline is available with the full text of this article at http://www.cdc.gov/ ncidod/hip/enviro/env_guide_draft.pdf) ( 1 ). A practical method to assess Fir qualityis to monitor airborne particles with in a certaln Size range using particle counters (2). Airbome particles and wind speed were continuously monitored in an NICU with five beds from 0:00 to 18:00 0n weekdays. The NICU was 199.6 m3 in size (76.75 m2floor space by 2.6 m high), and equipped with an anteroom of21. 1 m3 (8.1 m2floor space by 2.6 m high) and a fixed dusted room-air recirculation system with 85.4 % retum. As shown in a sketch of the NICU (Fig. I), four air-supply vents were located in the ceiling and fittedwith high-efficiency particulate air (HEPA) filters for air cleaning・ Two air-exhaust vents were located near the floor ln two comers and three were located in the ceiling. The volume of air supply was 4,800 m3/h, and the air changed 24 times per hour. In the room were seven incubators,including two spares,and five monitonng equlPment units, respirators, a radiant warmer, several shelves for solutions, medical supplies, records, and other materials. Air-