Unit 7.1.
Respiratory protection
TB Infection Control Training for
Managers at
National and Subnational Level
Objectives
After this unit, participants will be able:
• To describe the differences between a
surgical mask and a respirator
• To name the types of respirators that
protect against TB transmission, and
when to use them
• To list the elements of a respiratory
programme
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Outline
•
•
•
•
WHO recommendations
Surgical mask vs. particulate respirator
Respirator standards
Respirator programme
–
–
Proper use
Fit testing
3
WHO recommendations
•
When used with administrative and
environmental controls, particulate
respirators may provide health care
workers (HCW) additional protection
from TB
Respirators
•
–
–
–
Must meet or exceed standards
Be properly used
Be part of a training programme
4
WHO recommends particulate
respirators for HCWs:
•
Caring for patients with confirmed or
suspected infectious TB (in particular
MDR-TB)
Performing aerosol-generating
procedures on infectious TB patients
•
–
–
Bronchoscopy, intubation, sputum
induction
Use of high speed devices for lung surgery
or autopsy
5
Surgical masks
• Reduce the spread
of microorganisms
from the wearer to
others, by
capturing large wet
particles
• Do not protect the
wearer from
inhaling small
infectious aerosols.
6
Particulate respirators
• Protect the wearer
from inhaling
droplet nuclei
• Filter out infectious
aerosols
• Fit closely to the
face to prevent
leakage around the
edges
7
Proper wearing of respirators
(N95s and FFP2s) in Santa Cruz,
Bolivia
8
Surgical masks
(yes for patients)
9
Surgical masks
do not protect
staff from TB
10
Particulate respirators used for
TB exposure
N95 (USA)
FFP2, FFP3 (Europe)
Filter out > 95%
of particles
Filter out > 94-98%
of particles
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USA standards*
Filter
efficiency
N (not resistant TB
to oil)
protection
95%
99%
99.97%
N95
N99
N100
✓
✓
✓
*National Institute for Occupational Safety and
Health (NIOSH), Centers for Disease Control and
Prevention (CDC)
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European standards*
Total inward
leakage
Filtering
TB
Face Piece protection
<25%
FFP1
Not adequate
<11%
FFP2
✓
<5%
FFP3
✓
*Comité Européen de Normalisation (CEN)
(European Committee for Standardization)
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CEN standards
• Total inward leakage
• Initial filter penetration
NaCL
<20%=P1
< 6%=P2
< 3%=P3
Paraffin oil
NA=P1
<2%=P2
<1%=P3
• Maximum breathing resistance
• Loading test
14
Air-purifying respirators
Remove specific air contaminants by
passing ambient air through the airpurifying filter, cartridge or canister
15
Negative pressure respirators
• air pressure inside
the facepiece is
negative during
inhalation
• contaminated air
can avoid the higherresistance filter and
leak in through gaps
in the face seal
16
Types of air purifying
respirators
Non–powered (negative pressure)
Powered air-purifying respirators (PAPR)
• A blower draws air through the filter and
blows it into the face piece
• Pressure inside face piece reduces face-seal
leakage (offers more protection)
• Loose fitting PAPRs can be used for people
that cannot achieve an adequate seal
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Respirator programme elements
•
•
•
•
•
•
•
•
Person assigned responsibility
Written procedures
Medical evaluation
Training
Selection of respirators
Fit testing
Maintenance
Programme evaluation
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Why is fit testing necessary?
• Ensure a proper seal between respirator
and wearer
• Determine appropriate make/model
• Determine appropriate size
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When should fit testing be done?
Employees should pass a fit test:
• Prior to initial use
• Whenever a different respirator facepiece
(size, type, model or make) is used
• Periodically thereafter
• Whenever changes in the worker’s
physical condition or job description that
could affect respirator fit are noticed or
reported
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Sources of facepiece leakage
• Around facepiece/skin interface
• Through air-purifying element
• Through exhalation valve
21
Factors contributing to poor fit
•
•
•
•
•
•
•
•
Weight loss or gain
Facial scarring
Changes in dental configuration (dentures)
Facial hair
Cosmetic surgery
Excessive makeup
Mood of workers (smiling/ frowning)
Body movements
22
Qualitative fit tests:
• Rely on the
individual’s
response to the
test agent to
assess the
adequacy of
respirator fit
• Are scored as
pass/fail
23
Test solutions for
qualitative fit testing
Four methods recognized and accepted
•
•
•
•
Isoamyl acetate
Irritant aerosol
Saccharin
BitrexTM (Denatonium benzoate)
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Fit tests using saccharin or
BitrexTM
• Can be used for all respirators (i.e. 95-,
99- and 100- series and FFP2 and FFP3)
• Uses subject’s sense of taste
• Requires the use of small test hood
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Saccharin and BitrexTM
• Subject demonstrates ability to detect
weak solution in the test hood
• Subject dons respirator
• Strong solution (~100 times) sprayed into
hood
• Respirator passes if subject does not taste
aerosol
• Assumed fit factor = 100
26
Qualitative fit test equipment
27
Quantitative fit tests:
• Measure the
amount of leakage
into the respirator
to assess the
adequacy of
respirator fit
• Are scored with a
number
28
Maintenance and storage
• Take care of your disposable respirator
– Decontamination
NO!
– Cleaning
NO!
– Storage
Clean & dry place!
• Take care when re-using respirator –
closely monitor service life
• Inspect prior to each use
• Dispose of the respirator if you question its
performance
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Read the manufacturer’s
instructions to don the
respirator properly
30
Is this respirator put on
properly?
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Post warning sign
32
Time to clear the air between
patients
33
Bronchoschopy room
34
DOT room
35
Isolation
XDR-TB
tent and DOT
36
Summary
• Surgical masks prevent infectious particles
from being expelled by the wearer
• Respirators protect the health care worker
from inhaling infectious particles
• When used with administrative and
environmental controls, N95, FFP2 or
FFP3 respirators provide additional
protection when HCWs care for infectious
TB patients
• Whenever respirators are used, a
respirator programme is necessary
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