MIL-HDBK-1191
of the disease from the room. Protective Isolation rooms are provided for
the patient having an immune system deficiency, and require engineering
controls to assist in the protecting the patient from contamination from
outside the bedroom. Rooms shall be one or the other, and not "switchable"
from disease isolation to protective isolation function, or vice versa.
Isolation Bedrooms shall be provided with pressure-monitoring alarms and
gauges mounted on the outside corridor wall; when a central DDC control
operators station is provided, the alarm should in addition be connected to
that system.
8.17.1.
Disease Isolation Bedrooms. Disease Isolation bedrooms shall be
designed to incorporate requirements and guidance contained in the
Guidelines for Preventing the Transmission of Mycobacterium Tuberculosis in
Health-Care Facilities (the TB Guidelines), published in the Federal
Register Vol. 59, No. 208, 28 Oct 94 (or latest edition thereof). These
rooms shall be negatively pressurized and exhausted to the outside, and
provided with the minimum total and outside air change rates (12/2,
respectively) referenced at Appendix A. Exhaust ductwork from the bedrooms,
the associated toilet, and the anteroom (if provided) shall be "dedicated"
in the sense that the system may serve only the bedroom suite or other
disease isolation bedrooms. This exhaust system shall be connected to the
building emergency power system. Bedroom suites shall be supplied by air
systems provided with constant-volume control and measuring terminal units
which automatically maintain the supply air flowrate setpoint to each
space. Exhaust systems shall be constant volume systems maintaining a
fixed exhaust flow rate for each space.
When bedroom exhaust is located
such as to prevent reentrainment into outside air intakes or other building
openings, HEPA filtration of the exhaust is not required.
8.17.1.1
Existing Facilities. In existing facilities, only those
bedrooms designated by the facility specifically for use as Tuberculosis
Isolation Bedrooms are required to be designed in accordance with the TB
Guidelines referenced above. TB Isolation Bedrooms shall be negatively
pressurized and exhausted, and shall be provided with 12 air changes per
hour if economically or physically practicable. When not practicable to
achieve this air change rate, TB Isolation Bedrooms shall have a minimum of
6 air changes per hour, to be supplemented by HEPA filter or Ultra Violet
Germicidal Irradiation (UVGI) systems specifically designed for TB Room
applications and providing the equivalent of an additional 6 air changes
per hour. Fixed-in-place HEPA filtration units are preferable to portable
units, and upper-level UVGI systems are preferred over duct-mounted units,
to enhance reliability.
Room exhaust shall be conducted to the outside of
the building; when designed to avoid reentrainment into outside air intakes
or other building openings, HEPA filtration of the exhaust is not required.
8.17.1.2
Isolation Suite Relative Pressurization. When an anteroom is
provided for the isolation bedroom, interposing between the bedroom and
corridor to provide a "buffer" airspace for additional protection, there
are several recognized design approaches for corridor-anteroom-bedroom
relative pressurization. A recommended design is to provide for the
anteroom to be under negative pressure relative to the corridor, and
positively pressurized relative to the bedroom.
8.17.2
Protective Isolation Bedrooms. The air supply to the
protective isolation bedroom suite shall be constant flow and shall be
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