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S Step 2 Select Respiratorstep 2 Select Respirators
Respirator Selection For Protection
Respirator Selection For Protection
Against TB collected, the precise level of effectiveness
Against TB
in protecting HCWs [health care workers]
from M. tuberculosis transmission in health
Introduction care settings has not been determined. In-
Introduction
formation concerning the transmission of
Surgical masks are not respirators and are not certi- M. tuberculosis is incomplete. Neither the
fied as such; they do not protect the user adequately smallest infectious dose of M. tuberculosis
from exposure to TB. Disposable respirators (e.g., nor the highest level of exposure to M. tu-
N-95s) are commonly used in TB isolation rooms, berculosis at which transmission will not oc-
in transport of TB cases, or in other areas of the cur has been defined conclusively (59, 151,
health care facility. However, when high-risk pro- 152). Furthermore, the size distribution of
cedures such as bronchoscopy or autopsy are con- droplet nuclei and the number of particles
ducted, respiratory protection exceeding the CDC containing viable M. tuberculosis that are ex-
standard performance criteria may be needed. pelled by infectious TB patients have not
This protection includes full facepiece negative-pres- been defined adequately, and accurate
sure respirators, powered air-purifying respirators methods of measuring the concentration of
(PAPRs), or positive-pressure airline respirators infectious droplet nuclei in a room have not
equipped with a half-mask or full facepiece. been developed.
In addition, individual medical conditions such as
latex allergy, can influence respirator selections. La- Nevertheless, in certain settings the admin-
tex-free respirators are available. istrative and engineering controls may not
adequately protect HCWs from airborne
Additional information is provided below. droplet nuclei (e.g., in TB isolation rooms,
treatment rooms in which cough-inducing
or aerosol-generating procedures are per-
Supplement 4: Respiratory Protection
(Reprinted from [CDC 1994, Page 97]) formed, and ambulances during the trans-
port of infectious TB patients). Respiratory
protective devices used in these settings
I. Consideration for Selection of Respirators should have characteristics that are suitable
for the organism they are protecting against
Personal respiratory protection should be used and the settings in which they are used.
by a) persons entering rooms where patients
with known or suspected infectious TB are be- A. Performance Criteria for Personal
ing isolated, b) persons present during cough- Respirators for Protection Against
inducing or aerosol-generating procedures per- Transmission of M. tuberculosis
formed on such patients, and c) persons in other
settings where administrative and engineering Respiratory protective devices used in
controls are not likely to protect them from in- health care settings for protection against
haling infectious airborne droplet nuclei. These M. tuberculosis should meet the following
other settings should be identified on the basis standard criteria. These criteria are based
of the facility’s risk assessment. on currently available information, includ-
ing a) data on the effectiveness of respira-
Although data regarding the effectiveness tory protection against noninfectious
of respiratory protection from many haz- hazardous materials in workplaces other
ardous airborne materials have been than health care settings and on an inter-
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