Transcript Prevention of Work

Prevention of Workrelated SARS
Personal Protective Equipment
Hierarchy of methods of
hazard control
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Engineering control
Administrative control
Personal protective equipment
Control of infection
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Administrative control
Environmental control
Personal protective equipment
Control of transmission of
infectious disease
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Airborne
Droplet
Contact
Personal protective equipment
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Surgical mask
Respirator
Goggles
Gown
Gloves
Surgical mask
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Three layers
Standards and guidelines set in US by:
American National Standards Institute
The Association of Perioperative Registered
Nurses
American Study Society of Testing and
Materials
CDC
Surgical mask
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Food and Drug Administration
NIOSH
ASTM
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Categorize the surgical mask into general
use, sub-micron filtering, fluid resistant
Bacterial filtration efficiency
Differential pressure
Sub-micron particulate filtration
Resistance to penetration by synthetic blood
Flammability
Different types of surgical
mask
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Can be used with face shield or eyewear
Flat –fold tie on
Duck bill
Cone shaped
Flat-fold with shield
High fluid resistant
Things to observe in using a
surgical mask
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Worn properly
Comfortably cover the mouth and nose
Fit- no tenting around the side of the mouth
Use the pliable strip to promote a close fit
Change frequently when wet
Handle only the string and promptly dispose
into a waste receptacle
On or off
Respirators
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Purpose
Function
Respiratory protection program
Description and selection of
respirators
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NIOSH
Facepiece Classification: tight fitting
facepiece, loose –fitting facepiece
Tight fitting facepiece is further classified into:
quarter masks, half masks and full facepiece
Loose fitting facepieces include hoods,
helmets, blouses or full suits which cover the
head completely
Description and selection of
respirators
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Respirator classification :
Air purifying respirators
Atmosphere supplying respirators
Respirator selection
Hazard
Oxygen deficient
Toxic Contaminant
IDLH: No
IDLH: Yes
Particulate
Pressure-demand S.C.B.A.
Filter respirator
PAPR
Airline respirator
Pressure –demand
airline-respirator with escape provision
N95 respirator
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42 CFR 84
Use the most penetrating 0.3 AM aerodynamic
mass median diameter.
9 classes of filters- three levels of filter
efficiency and each with three categories of
resistance to filter efficiency degradation.
three levels of filter efficiency- 95%, 99% and
99.97%
three categories of resistance to filter efficiency
degradation- N, R, P.
N95 respirator
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N not resistant to oil
R resistant to oil
P oil proof
The N series are tested by a mildly degrading
aerosol of NaCl. The P- and R- series will be
tested against a highly degrading aerosol of
dicotylphthalate. The specific maximum loading
dose was 200mg. The N- and R- series is uaually
certified with a single work shift limitation
N95 respirator
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Certification of filters was based on statistical
evaluation of results from 30 filter tested.
Pass/ Fail test based on result from 20 filters
tested.
Fit test
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Seal check
Qualitative testing
Quantitative testing
Combined direct penetration through the filter
and leakage around the face seal
TSI 8020 Portacourt plus TM measures the fit
factors
Without surrogate fit testing, average exposure
was reduced to 33% of the ambient level, which
is much less protection expected of this class of
respirator, less than or equal to 10 %.
Fit test
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When fit tested first, greater protection than
normally expected (the average exposure
was reduced to 4% of the ambient level)
Without fit testing, person unknowingly may
have poor face seals, resulting in excessive
leakage and exposure.
An requirement by OSHA
Effects of respirator use
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Respiratory effects
Increased airways resistance
Increased dead space volume
Cough
Cardiovascular effects
Discomfort
Extraweight and Ergonomic concern
Psychological and social effects
Skin problems
Senses
Pregnancy
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No good data on respirator use in pregnancy
Most common cause for denying medical
clearance
Consider the risk of the work environment to
the mother and the developing child, the
capacity of the mother to tolerate the PPE, as
well as ergonomic consideration
Work condition
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Job characteristics
Work environment
Psychological stresses
Equipment –related stresses
Worker evaluation
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Work description
Medical history and physical examination
Special testing
Re-evaluation
Certification of use of
respirator
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Full use
Restricted use
Advice
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For infection control of patients with suspected
SARS, CDC advises airborne
precaution( including use of a N-95 filtering
disposable respirator), wearing of eye protection
and contact precaution was included in inpatient
setting and outpatient setting. A qualitative fit
test should be conduct for N95 respirator. If N95
respirator is not available, then surgical mask
should be worn. The patient should wear a
surgical mask.
Advice
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For precaution for Aerosol generating
procedures, CDC advises PPE should cover all
exposed skin- single isolation gown, a
disposable full-body isolation suit, a disposable
surgical hood with an attached face shield in
combination with a disposable respirator.
Disposable gloves
Eye protection
A face field
Disposable particulate respirators minimum
level of respiratory protection
Advice
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A fit test
A higher level of respiratory protection should
be used if fit test fails
Various types of PAPRs
Full facepiece elastometric negative
respirators with N, R or P100 filter
Advice
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WHO advises strict adherence with the barrier
nursing of patients with SARS using precautions
for airborne, droplet and contact transmission.
N95 respirator should be worn all the time when
attending patients with suspected and confirmed
SARS. The patient should wear a surgical mask.
All visitors, staff, students and volunteers
should also wear N95 in entering the room of a
patient with suspected or confirmed disease.
Surgical masks are a less effective alternative to
N95.
Advice
Hospital Authority advises:
Essential infection control advice
 All staff must receive infection control
precaution.
 All persons inside hospital setting must wear
a mask. For N95, ensure right size and
check the leakage.
 All person must practice hand hygiene.
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Advice
Personal Practice
All hospital settings
 All persons must wear a mask
 All must practice hand hygiene
All inpatient settings
 Standard precaution
 Droplet precautions: surgical mask for all patient
contact. Protective eyewear for close patient
contact.
Conclusion
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Last resort
Level of evidence: expert panel
Empirical measures based on the modes of
transmission when the full picture of the disease
is not known
Brief introduction of surgical mask and
respirator
Brief summary of how personal protective
equipment was recommended in various
organizations