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Identification of Factors That Disrupt Negative Air Pressurization of Respiratory Isolation Rooms

  • Nicholas Pavelchak (a1), Ronald P. DePersis (a1), Matthew London (a1), Rachel Stricof (a2), Margaret Oxtoby (a2), George DiFerdinando (a2) and Elizabeth Marshall (a1)...
Abstract
AbstractObjectives:

To investigate the airflow characteristics of respiratory isolation rooms (IRs) and to evaluate the use of visible smoke as a monitoring tool.

Methods:

Industrial hygienists from the New York State Department of Health evaluated 140 designated IRs in 38 facilities within New York State during 1992 to 1998. The rooms were located in the following settings: hospitals (59%), correctional facilities (40%), and nursing homes (1%). Each room was tested with visible smoke for directional airflow into the patient room (ie, negative air pressure relative to adjacent areas). Information was obtained on each facility's policies and procedures for maintaining and monitoring the operation of the IRs.

Results:

Inappropriate outward airflow was observed in 38% of the IRs tested. Multiple factors were associated with outward airflow direction, including ventilation systems not balanced (54% of failed rooms), shared anterooms (14%), turbulent airflow patterns (11%), and automated control system inaccuracies (10%). Of the 140 tested rooms, 38 (27%) had either electrical or mechanical devices to monitor air pressurization continuously. The direction of airflow at the door to 50% (19/38) of these rooms was the opposite of that indicated by the continuous monitors at the time of our evaluations. The inability of continuous monitors to indicate the direction of airflow was associated with instrument limitations (74%) and malfunction of the devices (26%). In one facility, daily smoke testing by infection control staff was responsible for identifying the malfunction of a state-of-the-art computerized ventilation monitoring and control system in a room housing a patient infectious with drug-resistant tuberculosis.

Conclusion:

A substantial percentage of IRs did not meet the negative air pressure criterion. These failures were associated with a variety of characteristics in the design and operation of the IRs. Our findings indicate that a balanced ventilation system does not guarantee inward airflow direction. Devices that continuously monitor and, in some cases, control the pressurization of IRs had poor reliability. This study demonstrates the utility of using visible smoke for testing directional airflow of IRs, whether or not continuous monitors are used. Institutional tuberculosis control programs should include provisions for appropriate monitoring and maintenance of IR systems on a frequent basis, including the use of visible smoke.

Copyright
Corresponding author
Department of Health, Division of Occupational Health and Environmental Epidemiology, Flanigan Square, 547 River St, Room 230, Troy, NY 12180
References
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1.Centers for Disease Control and Prevention. Guidelines for preventing the transmission of Mycobacterium tuberculosis in health-care facilities. MMWR 1994;43(RR-13):1132.
2. New York State Public Health Law, Title 10 NYCRR, section 712.31, Table 3 (February 29, 1988).
3.American Hospital Association, American Society for Hospital Engineering. TB control in the hospital environment. Healthcare Facilities Management Series Number: 055214. Chicago, IL: ASHE; May 1993.
4.American Society of Heating, Refrigerating, and Air-Conditioning Engineers. 1995 ASHRAE Applications Handbook. Atlanta, GA: American Society of Heating, Refrigerating, and Air-Conditioning Engineers, Inc; 1995:7.17.12.
5.The American Institute of Architects, Academy of Architecture for Health. Guidelines for Design and Construction of Hospital and Health Care Facilities. Washington, DC: The AIA Press; 1996.
6.American Conference of Governmental Industrial Hygienists. Industrial Ventilation: A Manual of Recommended Practice. 23rd ed. Cincinnati, OH: ACGIH; 1998.
7.Centers for Disease Control. Guidelines for preventing the transmission of tuberculosis in health-care settings, with special focus on HIV-related issues. MMWR 1990;39(RR-17):128.
8.US Department of Labor, Occupational Safety and Health Administration. Enforcement policies and procedures for occupational exposure to tuberculosis. Memorandum to regional administrators. Washington, DC: OSHA. October 8, 1993.
9.US Department of Labor, Occupational Safety and Health Administration. CPL 2.106. Enforcement procedures and scheduling for occupational exposure to tuberculosis. Washington, DC: OSHA. February 9, 1996.
10.US Department of Labor, Occupational Safety and Health Administration. Notice of proposed rule-making on Occupational Exposure to Tuberculosis (29 CFR 1910). Federal Register October 17, 1997;62:5415954309.
11.Burton DJ. Industrial Ventilation Workbook. Salt Lake City, UT: DJBA, Inc; 1989:15.115.4.
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Infection Control & Hospital Epidemiology
  • ISSN: 0899-823X
  • EISSN: 1559-6834
  • URL: /core/journals/infection-control-and-hospital-epidemiology
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