(b) Air supplied to the ambulatory care area can be recirculated and
returned back to the air handling unit provided the return air is
recirculated through high efficiency particulate air (HEPA) filters.
(c) HEPA filters shall be installed at the air-handling unit only. HEPA
filters installed in branch return air ducts will create air-balancing
problems.
(d) Germicidal UV Irradiation: The use of UV lamps in the return air ducts
is optional. It is not a requirement by CDC. The effectiveness of UV
lights is discussed in the CDC document. It is important that staff and
patients are protected from possible injury from the UV irradiation, and
the equipment be properly maintained.
negative pressure of at least 0.025 mm (0.001 inch) of water by exhausting
10 percent more air than the air supplied to them.
(a) Anterooms
(b) AFB Isolation Rooms
(c) Treatment Rooms
(d) TB Radiology Room
(e) TB Dental Operatory
(f) TB Dialysis Room
(g) Clinical Mycobacterial BSL3 Laboratories
(h) Note the following:
(1) The use of the anteroom is not mandatory for S/KI TB isolation rooms.
However, S/KI TB isolation rooms are often entered frequently and the use
of anterooms minimize the potential for droplet nuclei (airborne
infectious particles) spreading to the adjoining areas. The need for
anterooms should be discussed with the medical center.
(2) It is important to distinguish between the S/KI TB isolation rooms and
conventional isolation rooms with required reverse isolation capability.
With reverse isolation capability, the direction of air flow and the air
pressure and the patient rooms can be changed from positive to negative
with a change in the selector switch. S/KI TB Isolation rooms are to
remain under negative pressure at all times. S/KI TB patients shall not be
treated in a positive pressure environment.
(3) While conventional isolation room exhaust fans are required to be on
emergency power, CDC does not require TB isolation room exhaust fans to be
on emergency power. Therefore, consult the medical center staff for
providing emergency power for exhaust systems serving inpatient TB patient
rooms and some of the ambulatory care rooms designated for management of
TB patients. The potential risks to relative priority of other functions
covered by the emergency power should be carefully evaluated when
considering costly emergency power system expansion.
HVAC DESIGN MANUAL
3-28
HVAC REQUIREMENTS FOR OCCUPIED AREAS
Previous Page
