इंटरनेट मानक

Disclosure to Promote the Right To Information

Whereas the Parliament of India has set out to provide a practical regime of right to
information for citizens to secure access to information under the control of public authorities,
in order to promote transparency and accountability in the working of every public authority,
and whereas the attached publication of the Bureau of Indian Standards is of particular interest
to the public, particularly disadvantaged communities and those engaged in the pursuit of
education and knowledge, the attached public safety standard is made available to promote the
timely dissemination of this information in an accurate manner to the public.

“जान1 का अ+धकार, जी1 का अ+धकार” “प0रा1 को छोड न' 5 तरफ”

Mazdoor Kisan Shakti Sangathan Jawaharlal Nehru
“The Right to Information, The Right to Live” “Step Out From the Old to the New”

IS 9473 (2002): Respiratory Protective Devices - Filtering

Half Masks to Protect Against Particles [CHD 8:
Occupational Safety, Health and Chemical Hazards]

“!ान $ एक न' भारत का +नम-ण”

Satyanarayan Gangaram Pitroda
“Invent a New India Using Knowledge”

“!ान एक ऐसा खजाना > जो कभी च0राया नहB जा सकता ह”

है”
ह
Bhartṛhari—Nītiśatakam
“Knowledge is such a treasure which cannot be stolen”
 Is 9473:2002 -.
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Indian Standard
RESPIRATORY PROTECTIVE DEVICES —
FILTERING HALF MASKS TO PROTECT AGAINST
PARTICLES — SPECIFICATION
(First Revision)

Ics 13.340.30

(3 BIS 2002
BUREAU OF INDIAN STANDARDS ‘1
MANAK BHAVAN, 9 BAHADUR SHAH ZAFAR MARG
NEW DELHI 110002

November 2002 Price Group 11

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Industrial Safety and Chemical Hazards Sectional Committee, CHD 8 —

FOREWORD
This Indian Standard (First Revision) was adopted by the Bureau of Indian Standards, after the draft finalized
by the Industrial Safety and Chemical Hazards Sectional Committee had been approved by the Chemical Division
Council.
FiItering half masks are intended to provide adequate sealing on the face of the wearer of a respiratory protective
device against the ambient atmosphere, when the skin is dry or moist and when the head is moved. Air enters
the filtering half mask and passes directly to the nose and mouth area of the facepiece or, via an inhalation
valve, if fitted. The exhaled air flows through the filter material and/or an exhalation valve (if fitted) directly to
the ambient atmosphere.
These devices can be designed to protect against solid and water-based aerosols only or against both solid and
liquid aerosols where a solid aerosol is defined as a suspension of solid particles in air, a liquid aerosol is
defined as a suspension of liquid droplets in air and a water based aerosol is defined as one which is produced
from solutions and/or suspensions of s~lid materials in water such that the only hazardous component is
attributable to the solid material.
This standard was originally published in 1980 based on the standard “Title 30 — Mineral, Resources” issued
by U. S. Department of Health, Education and Welfare, Public Health Services, National Institute for Occupational
Safety and Health (NIOSH). With a view to update the standard due to the technological changes that took place
in the last two decades, the Committee felt a need to revise the standard and to align it with EN 149: 1991
‘Respiratory protective devices — Filtering half masks to protect against particles — Requirements, testing,
marking’. There is no ISO standard on this subject.
The composition of the Committee responsible for formulating this standard is given at Annex B.
For the purpose of deciding whether a particular requirement of this standard is complied with, the final value,
observed or calculated, expressing the result of a test or analysis, shall be rounded off in accordance with
1S 2: 1960 ‘Rules for rounding off numerical values (revised’. The number of significant places retained in the
rounded off value shall be the same as that of the specified value in this standard.

..

m
 Is 9473:2002

Indian Standard
RESPIRATORY PROTECTIVE DEVICES —
FILTERING HALF MASKS TO PROTECT AGAINST
PARTICLES — SPECIFICATION
(First Revision)
1 SCOPE b) FFP2, and
1.1 This standard prescribes requirements and method c) FFP3 .
of sampling and tests for filtering half masks as NOTE — FFP 1filters are intended for use against solid particles
respiratory protective devices against particles except only. FFP2 and FFP3 filters are sub-divided according to their
for escape purposes. ability to remove both solid and liquid particles or solid particles
only. The protectionprovidedby FFP2 filter or FFP3 filter includes
NOrE — Laboratory and practical performancetests are included
t’orthe assessment of compliance with the requirements. that provided by the corresponding filter of lower class or classes.

2 REFERENCES 5 REQUIREMENTS

The Indian Standards listed below contain provisions, 5.1 Material

which through reference in this text constitute
5.1.1 When subjected to the conditioning described
provisions of this Indian Standard. At the time of
in A-1, none of the filtering half masks shall have
publication, the editions indicated were valid. All
suffered deformation of the face piece or straps. Three
standards are subject to revisions, and parties to filtering half masks shall be tes;ed. -
agreements based on this standard are encouraged to
investigate the possibility of applying the most recent 5.1.2 When subjected to conditioning in accordance
edit ions of the standards indicated below: with A-1.l and A-1.2, the filtering half mask shall
not collapse.
IS No. Title
4905:1968 Methods of random sampling 5.1.3 Any material from the filter media released by
8347:1977 Glossary of terms relating to the air flow through the filter should not constitute a
respirato~ protective devices - hazard or nuisance for the wearer.
14166: 994 Respiratory protective devices — 5.1,4 Metal
Full face masks — Specification
The use of aluminium, magnesium and titanium or
14746: 999 Respiratory protective devices —
alloys containing such proportions of these metals as
Half masks and quarter masks —
will, on impact, give rise to frictional sparks capable
Specification
of igniting flammable gas mixtures for exposed parts
3 TERMINOLOGY (those which may be subjected to impact during the
use of apparatus) shall be restricted to a minimum.
3.1 For the purpose of this standard, the definitions
given in IS 8347 and the term given below shall apply. 5.2 Cleaning and Disinfecting
3.1.1 Filtering Halj Mask The materials used shall withstand the cleaning and
disinfecting agents recommended by the manufacturer.
A filtering half mask is one which covers the nose
and mouth and possibly the chin and NOTE—This is applicable if the filtering hrdfmask is designed
for more than a single shitl (not designed for single use only).
a) consists entirely or substantially of filter
material, or 5.3 Practical Performance Test
b) comprises a face piece in which the main The filtering half mask shall undergo practical
filter(s) form an inseparable part of the device performance tests under realistic conditions, These
and where the pre-tilter may be replaceable. general tests serve the purpose of checking the
equipment for imperfections that cannot be determined
4 CLASS by the tests described elsewhere in this standard.
4.1 Filtering Ialf masks shall be of following three Where a filtering half mask is to be used for filtering
classes: devices, testing shall be in accordance with A-2.

a) FFP When practical performance tests show the apparatus

has imperfections related to wearer’s acceptance, full

1
Is 9473:2002

details of those parts ofpractical performance tests, 5.6 Flammability

which revealed these imperfections, shall be provided.
The material used shall not present a danger for the
This will enable during subsequent testing of the masks
wearer and shall not be of highly flammable nature.
to repeat the tests and assess the results thereof.
When tested in accordance with A-5, the face piece
5.4 Leakage shall not continue to bum after removal from the flame.
NOTE — It is not required that the filtering half mask still has to
5.4.1 Total Inward Leakage
be usable after the test.
5.4.1.1 When tested according to A-3, the filtering half
masks fitted in accordance with the manufacturer’s 5.7 Carbon Dioxide Content of the Inhalation Air
instruction, at least 46 out of 50 individual exercise When tested in accordance with A-6, the carbon
results (that is, 10 subjects x 5 exercises) for the total dioxide content of the inhalation air (dead space) shall
inward leakage: not exceed an average of 1.0 percent ( by volume).
a) shall not be greater than 25 percent for FFP1, 5.8 Head Harness
I 1 percent for FFP2 and 5 percent for
FFP3; and 5.8.1 The head harness shall be so designed that the
b) at least 8 out of 10 individual wearer filtering half mask can be donned and removed easily,
arithmetic means for the total inward leakage when tested in accordance with A-2.
shall not be greater than 22 percent for FFP 1, 5.8.2 The head harness shall be adjustable or self-
8 percent for FFP2 and 2 percent for FFP3. adjusting and shall hold the filtering half mask firm Iy
NOTES and comfortably in position, and be capable of
1 The total inward leakage consists ofthree componen~ (a) face maintaining total inward leakage requirements for the
seal leakage, (b) exhalation valve leakage (if exhalation valve device when tested in accordance with A-2 and A-3.
fitted), and (c) filter penetration.
2 The test indicates that the iiltering half mask can be used by the 5.9 Field of Vision
wearer to protectwith high probability againstthe potentialharard
to be expected, The field of vision shall be acceptable when
determined so during the practical performance tests
5.4.2 Penetration of Filter Material in accordance with A-2. Comparative testing of the
The penetration of the filter of the filtering half mask field of vision is carried out in accordance with the
shall meet the requirements given in Table 1. method described in A-8 of IS 14746.

5.10 Inhalation and Exhalation Valves

Table 1 Penetration of Filter Material
5.10.1 Inhalation Valve(s)
SI Characteristics Requirements Method
No. of Test, A filtering half mask may have one or more inhalation
~ Ref to Cl valve(s).
FFPI FFP2 FFP3
(1) (2) (3) (4) (5) (6) 5.10.2 Exhalation Valve(s)
i) Sodium chloride 20 63 A-4.2
test : Initial penet- (see Note) 5.10.2.1 A filtering half mask may have one or more
ration of sodium exhalation valve(s) and, if fitted, shall function
chloride test aerosol correctly in all orientations, when tested according
~J5 Ipm, percent, to A-3.
ii) Pamftin oil test : – 2 I A-4.3 5.10.2.2 If an exhalation valve is provided, it shall be
Initial penetration of (see Note)
paraftin oil @ 95 protected against dirt and mechanical damage, and
Ipm, percent, Max shall be shrouded or shall include any other device
NOTE — A total of 12 tiltering half masks shall be tested for
that may be necessary for the filtering half mask to
each aerosol: 3 as received, 3 atter temperature conditioning in comply with A-3.
accordance with A-I.2, 3 afier the simulated wearing treatment
in accordance with A-1.l and 3 after the test for mechanical 5.10.2.3 If an exhalation valve is provided, it shall
strength in accordance with A- 1.3. continue to operate correctly after a continous
exhalation flow of 300 Ilmin over a period of 30 s. A
total of 3 filtering half masks shall be tested; one as
5.5 Compatibility with Skin received and 2 temperature conditioned in accordance
Materials that may come into contact with the wearer’s with A-1 .2.
skin shall not be known to have potential to cause 5.10.2.4 When the exhalation valve housing is
irritation or any adverse effect to health. attached to the face blank, it shall withstand axial Iy a

2
 Is 9473:2002

tensile force of 10 N applied for 10 s, when tested in 5.13 De-mountable Parts

accordance with A-7.
All de-mountable parts (if fitted) shall be readily
5.11 Breathing Resistance connected and secured, where possible by hand when
tested according to A-11.
The breathing resistance of the valved and valveless
filtering masks shall meet the requirements given in 6 PACKING AND MARKING
Table 2.
6.1 Packing
Table 2 Breathing Resistance
SI Characteristics Requirements Method The material shall be packed suitably as agreed to’
No. of Test, between the seller and the purchaser to prevent any
~ Ref to Cl damages during handling and transportation.
FFP 1 FFP2 FFP3
(1) (2) (3) (4) (5) (6) 6.2 Marking
I Permitted resistance, A-8
mbar, Max 6.2.1 Filtering Half Mask
– Inhalation @ 30 l/rein 0.6 0.7 I .0
– inhalation@ 95 l/rein 2.1 2.4 3.0 Filtering half masks shall be clearly and durably
2 Permitted resistance, A-8 marked with the following information:
mbar, Max
– Exhalation @ 160 l/rein 3.0 3.0 3.0 a) The name, trade-mark or other means of
I mbar= 10$N/m2= 100kP~ 1 bar= 10s Pa; 1 mbar= 100kPa. identification of the manufacturer;
b) Class : FFP1, FFP2 or FFP3;
c) The letter S (solid) or SL (solid and liquid)
5.12 Clogging
in accordance with filter penetration
5.12.1 Two types of tests are available using coal dust performance. These letters shall follow the
for coal mining use and dolomite dust for other class designation [see (b) above];
applications. Devices designed to be resistant to d) If appropriate the letter D (dolomite) or C
clogging (slow increase of breathing resistance when (coal) in accordance with clogging perfor-
loaded with dust) shall be subjected to the treatment mance. These letters shall follow the class
in accordance with A-9. designation [see (b) above]; and
NOTES e) Sub-assemblies and components with
1 Respirators shall be tested for clogging either with coal dust or considerable bearing on safety shall be
dolomite depending on the end use. marked so that they can be identified.
2 For single use respirator, this testis optional. NOTE — Colours do not represent a colour code, this means that
5.12.2 Breathing Resistance After Clogging colours are not related to protection provided,

5.12.2.1 ValvedJltering half masks 6.2.2 The package of the filtering half masks
complying with this standard shall be clearly and
a) The inhalation resistance shall not be greater durably marked with the following information:
than 4 mbar for FFP 1 and 5 mbar for FFP2
when tested for breathing resistance at a) The name, trade-mark or other means of
95 l/rein, in accordance with A-8 after the identification of the manufacturer;
treatment. b) Class : FFP1, FFP2, FFP3;
b) The exhalation resistance shall not be greater c) The year of manufacture plus the rated shelf
than 3 mbar at 160 l/rein continuous flow. life or the date of expiry of rated shelf life
(where the reliable performance may be
5.12.2.2 Valveless jiltering half masks
affected by ageing);
The inhalation and exhalation resistances shall not d) The sentence ‘see instructions for use’; and
be greater than 3 mbar for FFP1 and 4 mbar for FFP2, e) The package of filtering half masks which
when tested for breathing resistance at 95 l/rein do not passthe paraffin o~ltest shall be clearly
continuous flow, in accordance with A-8. marked ‘For use against solid aerosols only’.
5.12.3 Fi[ter Penetration
NOTE — This may include water based aerosols (see 4.1).
All filtering half masks (valved and valveless) which
6.2.3 BIS Certlflcation Marking
meet the clogging requirement (see 5.12.1 and 5.12.2)
shall also comply with the penetration requirements The filtering half masks may also be marked w ith the
given in 5.4.2 atler the treatment. Standard Mark.

3
 -.
Is 9473:2002 .

6.2.3.1 Theuseofthe Standard Mark isgovernedby under uniform conditions of manufacture on the same
the provisions of the Bureau oflndian Standards Act, day shall constitute a lot.
1986 and the Rules and Regulations made thereunder.
8.1.1 Each lot shall be tested separately for
Hle details of conditions under which the Iicence for
ascertaining the conformity of the lot to the
usc of the Standard Mark may be granted to
requirements of the specification. The number of half
manufacturers or producers may be obtained from the
masks to be selected from the lot shall depend upon
Bureau of Indian Standards.
the size of the lot and shall be in accordance with
7 INSTRUCTIONS FOR USE Table 3.

7.1 Instructions for use shall accompany every filtering 8.1.2 The masks shall be selected at random from the
half mask. lot. For this purpose, reference may be made to
Is 4905.
7.2 Instructions for use shall be in one or more
languages acceptable to the country of application. Table 3 Number of Samples to be
7.3 The instructions for use of the equipment shall Tested from a Lot
contain all information necessary for trained and (Clause 8.1. 1)
qualified persons on the following:
S1No. No. of Half Masks No. of Half Masks to be
a) Application/limitation; in the Lot Selected in a Sample
The information only for single use, if (1) (2) (3)
b)
i) upto50 12
applicable; ii) 51to 150 13
c) State the suitability of the filters marked for iii) 151 and above 20
solid aerosols only, against water based
aerosols defined as: water based aerosols are 8.2 Number of Tests
those produced from solutions and/or
8.2.1 Each of the half masks selected from the lot,
suspensions of particulate materials in water
according to COI2 of Table 3 shall be examined for
such that the only workplace contaminant is
visual inspection (5. 13) and field of vision (5.9).
attributed to this solid material;
d) Checks prior to use; 8.2.1.1 The lot shall be considered to have satisfied
e) Donning, fitting; the above requirements if none of the masks in the
sample fails. Otherwise, the lot shall be rejected.
o Use;
~) Maintenance (preferably separately printed 8.2.2 From the samples having been found satisfactory
instructions); and as per 8.2.1, required number of samples according to
h) Storage. CO13 of Table 3 shall be further tested for the
requirements of carbon dioxide content (5.7),
7.4 The instructions shall be unambiguous if helpful, breathing resistance (5.1 1), practical performance test
illustrations, part numbers, marking, etc, shail be
(5.3), and cleaning and disinfection (5.2) in this
added.
sequence.
7.5 Warn ing shall be given against problems likely to
8.2.2.1 The lot shall be considered to have satisfied
be encountered, for example, fit of filtering half mask
the above requirements if there is no failure in the
(check prior to use); it is unlikely that the requirements
for leakage will be achieved if facial, hair passes under sample. Otherwise, the lot shall be rejected.
the face seal; air quality (contaminants, oxygen 8.2.3 Required number of masks, out of the sample
deficiency); use of equipment in explosive atmosphere; already been found satisfactory as per 8.2.2 shall be
and filtering half masks which do not pass the paraffin drawn and made into two parts.
oil test shall be used against solid and water-based
aerosols only. 8.2.3.1 The samples under one part shall be
conditioned as per A-1 and shall be tested for leakage
7.6 The instructions shall indicate that single-use of half masks (5.4), flammability (5.6), and inhalation
tiltering half masks shall be discarded after single-use. and exhalation valve (5.1O), if fitted, and clogging.
8 SAMPLING AND CRITERIA FOR 8.2.3.2 The samples under other part shall be tested
CONFORMITY for the requirements of leakage (5.4), flammability
(5.6), head harness tests (5.8), exhalation valves
8.1 Lot
(5.10.2), performance tests (5.3) and exhalation valves
In a single consignment, all the half masks assembled housing (5.10.2.4).

4
 IS 9473:2002

8.2.3.3 The lot shall be considered as conforming to and 8.2.3.2. Otherwise the lot shall bereiected.
the requirements of this specification if all ~he
8.3 A summary of tests applicable for half masks is
half masks pass the requirements specified in 8.2.3.1
given in Table 4.

Table 4 Summary of Tests

S1No. No. of Samples Test Criteria Conditioning (Yes/No) Clause

(1) (2) (3) (4) (5)
i) All Visual inspection A.R. A-11

ii) 5 Cleaning and disinfection A.R. As per manufacturer’s

instructions
iii) 4 Flammability A.R. (2) A-5
T.C. (2)
iv) 3 Carbon dioxide content AR. A-6

v) 3 Exhalation valve pull A.R. (1) A-7

S.w. (1)
T.C. (1)
vi) 3 Exhalation valve flow A.R. (1) —
T.C. (2)

vii) 9 Breathing resistance A.R. (3) A-8

S.w. (3)
T.C. (3)
viii) 12 (for each Particle filter penetration A.Il. (3) A-4
aerosol) S.w. (3)
T.C. (3)
M.S. (3)
ix) 10 Total inward leakage AR. (5) A-3
T.C. (5)
~) 6 Clogging test (Optional for FFP1 A.R. (2) A-9
+ FFP2 singleuse devices on]y)’) T.C. (2)
M.S. (2)
xi) 2 Practical performance A,R. A-2

AR, As received 1)Twote5@availab]e:

MS. Mechanical strength a) Coal dust: forminingapplications
S.W. Simulatedwearingtreatment b) Dolomite dust: for other applications
T.C. Temperature conditioned

ANNEX A
(Clauses 5.1.1,5.1.2,5.3,5.4.1.1, 5.4.2,5.6,5.7,5.8.1, 5.8.2,5 .9,5.10 .2.1,5 .10.2.2,
5.10.2.3, 5.10.2.4,5,11, 5.12.1,5.12.2.1, 5.12.2 .2,5.12.3 and5.13)
METHODS OF TESTS FOR FILTERING HALF MASKS

A-1 CONDITIONING breathing machine and the dummy head, the saturator
being set in a temperature in excess of 37°C to allow
A-1.1 Simulated Wearing Treatment.
for cooling of the air before it reaches the mouth of
Conditioning by simulated wearing treatment shall be the dummy head. The air shall be saturated at 37 + 2°C
carried out by the following process. at the mouth of the dummy head. In order to prevent
A breathing machine is adjusted to 25 cycleslmin and excess water spilling out of the dummy’s mouth and
21/stroke. The filtering half mask is mounted on a contaminating the filtering half mask, the head shall
Sheffield dummy head, For testing, a saturator is be inclined so that the water runs away from the mouth .
incorporated in the exhalation line between the and is collected in a trap.

5
Is 9473:2002

The breathing machine is brought into operation, the which can be expected during normal use. During this
saturator switched on and the apparatus allowed to test, the following activities shall be carried out in
stabilize. The filtering half mask under the test shall simulation of the practical use of the filtering half
then be mounted on the dummy head. During the test mask. The test shall be completed within a total
time at approximately 20 min intervals, the filtering ‘ working time of 20 min.
half mask shall be completely removed from the
dummy head and refitted such that during the test The sequence of activities is at the discretion of the
period, it is fitted ten times to the dummy head. test station. The individual activities shall be arranged
so that sufficient time is left for the comments
A-1.2 Temperature Conditioning prescribed.
The filtering half masks shalI be exposed to the a) Walking on the level with headroom of
following thermal cycle: 1.3 * 0.2 m for 5 min.
a) for 24 h to a dry atmosphere of 70 + 3“C, b) Crawling on the level with head room of
0.7 * 0.05 m for 5 min.
b) for 24 h to a temperature of –30 * 3“C, and
c) Filling a small basket (see Fig. 1,
allowed to return to room temperature for at least 4 h approximate volume = 8 1) with rubber
between exposures and prior to subsequent testing. chippings or other suitable material from a
hopper which stands 1.5 m high and has an
A-1.3 Mechanical Strength
opening at the bottom to allow the contents
Before testing for breathing resistance, filtration to be shovelled out and a fiwther opening at
efficiency and clogging, the filter shall be subjected the top where the basket full of rubber
to a test in accordance with A-10 simulating rough chippings shall be returned.
usage of fiher. After this treatment, the filters shall
show no mechanical defects and shall meet the
requirements for breathing resistance, filtration
efficiency and clogging.
/
A-2 PRACTICAL PERFORMANCE TEST
A total of 2 filtering half masks shall be tested, both
as received. All tests shall be carried out by two test
subjects at ambient temperature, and the test
temperature and humidity shall be recorded. Prior to
the test, there shall be an examination as per A-11 to
assure that the filtering half mask is in good working
condition and that it can be used without hazard. For
the test, persons shall be selected who are familiar E
with using such or similar equipment. During the te$ts, m
the filtering half mask shall be subjectively assessed
by the wearer and after the test, comments on the
following shall be recorded:
a) Head harness comfort,
b) Security of fastenings,
c) Field of vision, and
d) Any other comments reported by the wearer /
on request.

A-2. 1 Walking Test

The subjects wearing normal working clothes and
wearing the filtering half mask shall walk at a regular
rate of 6 km/h on a level course. The test shall be
continuous without removal of the filtering half mask
for a period of 10 min.

A-2.2 Work Simulation Test

The filtering half mask shall be tested under conditions FIG. 1 BASKET ANDHOPPER, RUBBER CHIPPINGS

6
 Is 9473:2002

The subject shall stoop or kneel as he wishes and fill the enclosure through a flow distributor and be directed
the basket with rubber chippings. He shall then lifi downwards over the head of the test subject at a
the basket and empty the contents back into the hopper. minimum flow rate of 0.12 m/s. The concentration of
This shall be done 20 times in 10 min. the test agent inside the effective working volume shall
be checked to be homogeneous. The flow rate should
A-3 LEAKAGE be measured close to the subject’s head.
A-3. 1 General Test Procedure A-3. 1.4 Test Procedure
A-3.1.1 Total Inward Leakage The test subjects shall be asked to read to
manufacturer’s fitting instructions and if more than
A total of 10 test specimens shall be tested; 5 as
one size of filtering half mask is manufactured, the
received and 5 after temperature conditioning in
test subject shall be asked to select the size deemed by
accordance with A-1.2. The inward leakage shall be
him to be the most appropriate. If necessary, the
tested using a solid aerosol. The reference method is
subjects shall be shown by the test supervisor how to
the sodium chloride aerosol test. Prior to the test, there
fit the filtering half mask correctly in accordance with
shall be an examination as per A-11 to ensure that the
the fitting instructions.
filtering half mask is in good working condition and
that it can be used without hazard. The test subjects shall be informed that if they wish to
adjust the filtering half mask during the test they may
For the test, persons shall be selected who are familiar
do so. However, if this is done, the relevant section of
with using such or similar equipment. A panel often
the test shall be repeated having allowed the system
clean-shaven persons (without beards or sideburns)
tore-settle.
shal I be selected covering the spectrum of facial
characteristics of typical users (excluding significant The test subjects shall have no indication of the results
abnormalities). It is to be expected that exceptionally as the test proceeds, After fitting the filtering half mask
some persons cannot be satisfactorily fitted with a each test subject shall be asked ‘Does the mask fit’? If
filtering half mask. Such exceptional subjects shall the answer is ‘Yes’, continue the test. If the answer is
not be used for testing filtering half masks. ‘No’, take the test subject off the panel, report the fact
and replace with another test subject. The test sequence
In the test report, the faces of the ten test subjects shall
shall be as follows:
be described (for information only) by the four facial
dimensions (in mm) illustrated in Fig. 2. a) Ensure the test atmosphere is OFF.
A-3. 1.2 Apparatus b) Place the test subject in the enclosure.
Connect up the face piece sampling probe.
A-3. 1.2.1 Treadmill Have the test subject walk at 6 kdh for 2 min.
A level treadmill is required which is capable of Measure the test agent concentration iqside
working at 6 km/h. the filtering half mask to establish the
background level.
A-3.1.3 Test Atmosphere c) Obtain a stable reading.
The test atmosphere shall preferably enter the top of d) Turn the test atmosphere ON.

LENGTH OF WIDTH OF DEPTH OF WIDTH OF

FACE FACE FACE THE MOUTH
(NASlON-MENTON) (BIZYG”OMATIC
DIAMETER)

FIG. 2 FACIAL DIMENSIONS

7
Is 9473:2002

e) The subject shall continue to walk for a 3.1.5 Results

further 2 min or until the test atmosphere has
Record the following as test results:
stabilized.
0 Whilst still walking the subject shall perform a) Enclosure concentration.
following exercises: b) The leakage over each exercise period.
1) Walking for 2 min without head A-3.2 Sodium Chloride (NaCl) — Method
movement or talking.
A-3.2.1 Principle
2) Turning head from side to side
(approximately 15 times), as if The subject wearing the filtering half mask under test
inspecting the walls of a tunnel for 2 min. walks on a treadmill over which is an enclosure.
3) Moving the head up and down Through this enclosure flows a constant concentration
(approximately 15 times), as if of NaCl aerosol, The air inside the filtering half mask
inspecting the roof and floor for 2 min. is sampled and analyzed during the inhalation phase
4) Reciting the alphabet or an agreed text of the respiratory cycle to determine the NaCl content.
out loud as if communicating with a The sample is extracted by punching a hole in the
colleague for 2 min. filtering half mask and inserting a probe through
which the sample is drawn. The pressure variation
5) Walking for 2 min without head
inside the filtering half mask is used to actuate a
movement or talking.
change-over valve so that inhaled air only is sampled.
!4 Turn off the test atmosphere and when the test A second probe is inserted for this purpose.
agent has cleared from the enclosure, remove
the subject. After each test the filtering half A-3.2.2 Apparatus
mask shall be replaced by a new sample. A-3.2.2.1 Test equipment (see Fig. 3)

w“
32
9

13
4!

1 Atomizer 8 Manometer
2 Pump 9 Photometer
3 Change-over vaive 10 Filtering half mask
4 Filter 11 Treadmill
5 Enclosure 12 Ducting and baftle
6 Enclosure sample 13 Additional air ‘1
7 Mask sample 14 Pulsed sampling interface

FIG. 3 TYPICAL APPARATUSUSED IN THEDETERMINATIONOF INWARDLEAKAGEUSING SODIUMCHLORIDE

.
 IS 9473:2002

A-3.2.2.2 Aerosol generator 100 l/rein at a pressure of 7 bar. The atomizer and its
housing shall be fitted into a duct through which a
The NaCl aerosol shall be generated from a 2 percent
constant flow of air is maintained. It maybe necessary
solution of reagent grade NaCl in distilled water. An
to hat or dehumidify the air in order to obtain complete
atomizer equivalent to the type described should be
drying of the aerosol particles.
used (see Fig. 4). This requires an air flow rate of
+0.013 +0

4.8-
1=

t-%

@O.74 DRILL I

ENLARGED VIEW A
120’3

ILL
DRILLED013
TO ACCOMMODATE
@4. KFEED TUBEAS SHOWN

Item List
! Item I Name l. No. Ofl I
— Assembly of atomizer -
, 1
1 Nozzle 1
III20.6~ 0.6
2 Feed tube salt solution 1

3 Bottle polythene 1

4 Sieve 1

] 5 ] Screw cao for bottle I 1 I

I 6 \ Washer25 x13x3.2 I 1 !

178
r
Washer 9.5 x 4.8x 2.4

‘O’ seal
1
1

1
1
9 Air tube As required
Major +13
ATOMIZER
Minor 6.5

NOTE— All bums and sharpedgesto be removed.MAT. Stainlesssteel.

All dimensionsin millimebes.
FIG. 4 ASSEMBLY OF ATOMIZER

\\
Is 9473:2002

A-3.2.2.3 Test agent c) An interfacing system to actuate the valve in

response to a signal from the pressure sensor.
The mean NaCl concentration within the enclosure
shal I be 8 + 4 mg/m3 and the variation throughout the d) A timing device to record the proportion of
effective working volume shall be not more than 10 the total respiratory cycle during which
percent. The particle size distribution shall be 0.02 sampling took place.
to 2 ~m equivalent aerodynamic diameter with a mass A-3.2.2.6 Sampling probe
median diameter of 0.6 pm.
The probe shall be fitted securely in an air-tight
A-3.2.2.4 Flame photometer manner to the filtering half mask as near as possible
to the centre line of the filtering half mask. A multiple
A flame photometer shall be used to measure the
hole sampling probe is strongly recommended.
concentration of NaCl inside the filtering half mask.
Measures shall be taken to prevent the influence of
Essential performance characteristics for a suitable
condensation in the sampling probe on the measure-
instrument are as follows:
ment (by supplying dry air). Figure 5 shows a design
a) It should be a flame photometer specifically that has been found suitable. The probe is adjusted so
designed for the direct analysis of NaCl that it just touches the wearer’s lips.
aerosol.
A-3.2.2.7 Sample pump
b) It should be capable of measuring
concentrations of NaCl aerosol between If no pump is incorporated into the photometer, an
15 mg/m3 and 5 mg/m3. adjustable flow pump is used to withdraw an air sample
c) The total aerosol sample required by the from the filtering half mask under test. This pump is
photometer should not be greater than 15 l/rein. so adjusted as to withdraw a constant flow of
1 l/rein fkom the sample probe. Dependent on the type
d) The response time of the photometer,
of photometer, it may necessary to dilute the sample
excluding the sampling system, should not
with clean air.
be greater than 500 milliseconds.
e) It is necessary to reduce the response to other A-3.2.2.8 Sampling of enclosure concentration
elements, particularly carbon, the concen- The aerosol enclosure concentration is monitored
tration of which will vary during the breathing during the tests using a separate sampling system to
cycle. This will be achieved by ensuring that avoid contamination of the filtering half mask
the band pass width of the interference filter sampling lines. It is preferable to use a separate flame
is not greater than 3 nm and that all necessary photometer for this purpose.
side band filters are included.
If a second photometer is not available, sampling of
A-3.2.2.5 Sample selector the enclosure concentration using a separate sampling
A system is required which will switch the sample to system and the same photometer may be made.
the photometer only during the inhalation phase of However, time will then be required to allow the
the respiratory cycle. During the exhalation phase, photometer to return to a clean background.
clean air shall be fed to the photometer. The essential A-3.2.2.9 Pressure detection probe
elements of such a system are as follows:
A second probe is fitted near to the sample probe and
a) An electrically operated valve with a response is connected to the pressure sensor.
time of the order of 100 ms. The valve should
have the minimum possible dead space A-3.2.3 Expression of Results
compatible with straight-through, un- The leakage P shall be calculated from the measure-
restricted follow when open. ments made over the last 100s of each of the exercise
b) A pressure sensor which is capable of periods to avoid carry over of results from one exercise
detecting a minimum pressure change of to another.
approximately 0.05 mbar and which can be p=+x~
c x t +tExxloo
connected to a probe inserted in the cavity of L,, tm
where
the filtering half mask. The sensor shall have
an adjustable threshold and be capable of c, = Challenge concentration,
differential signaling when the threshold is c, = Measured mean concentration,
crossed in either direction. The sensor shall t=IN Total duration of inhalation,
work reliably when subjected to the accelera-
t= total duration of exhalation, and
tions produced by the head movements of the
subject.
;= leakage in percent.

10
 1S9473 :2002

CLEARPVC
w
I I I I
/////////////// ‘/--

.
I
I_+ I
l— I
1
4 . ..-.---.-.-+--- -—-.--:-+------’ -----
-t-
c ~
1~
I
m l!
m D
e ; ,i i;
--------- -----.— ~.
I &—-—--—”—..--—-.-&.+-—————.
+
\
\\\\\\!\\\\\
I I

SAMPLE PLUS
DRYING AIR
1- DIA 9
-
DRYING AIR

MATERIALPVC

All dimensionsin millimetres.

FIG.5 SAMPLEPROEE

Measurement ofC2 is preferably made using an A-4.2.1 Apparatus

integrating recorder.
The apparatus is shown in Fig. 6. The aerosol is
A-4 F1LTRATION EFFICIENCY
generated using a Collison atomizer filled with
1 percent solution of sodium chloride. The atomizer,
A-4.1 The filters shall be tested before and after the which is shown in Fig. 7, consists ofa glass reservoir
following temperature treatment. The filters shall be into which is sealed an atomizer head having three
exposed for: spray nozzles. Air is supplied to the atomizer at a
pressure of 3.45 bar and the resulting liquid spray
a) 24 h to dry atmosphere of 70 + 3*C, and
impinges on a baffle which removes the large particles.
b) 24 h to temperature of –30 + 3°C. The particles which do not impact are removed in the
The methods used for testing filters against solid and air flow and, on mixing with dry air, the water
liquid aerosols are: evaporates leaving a dry sodium chloride aerosol.

a) sodium chloride test according to A-4.2, and The aerosol produced by this method is polydisperse
with a mass median particle diameter of approximately
b) paraffin oil test according to A-4.3.
0.6 ~m. The particle size distribution is given in Fig. 8.
Sodium ch Ioride test according to A-4.2 is the only It has been found that the aerosol remains constant
method used for testing filters against solid aerosols. within acceptable limits with respect to particle size
and concentration provided that the supply pressure
Each test shall be made with 3 specimens. is in the range of 3.31-3.59 bar and the flow rate of
air to the three nozzles is 12.5-13.0 l/rein. The output
A-4. 1 Sodium Chloride Test
is mixed with 82 1/rein of dry air giving a total flow
An aerosol of sodium chloride particles is generated of 95 l/rein.
by atomizing an aqueous solution of the salt and
The salt solution in the atomizer is ccmsumed at a
evaporating the water. The concentration of this rate of approximately 15 ml/h. This loss is due in
aerosol is measured before and after the filter under part to the atomization of the solution and in part to
the test by means of flame photometry. Accurate evaporation of water from the reservoir. The volume
determinations are possible in the range <0.00001 of the reservoir is such that the change in concentration
to I00 percent filter penetration. and loss in volume of the solution during an 8-h period

11

\\
‘,
1s 9473:2002

EXHAUST
r COMPRESSED EXHAUST
AIR
A

TEST AEROSOL
TEST
![ — CHAM8ER ? MEASURING
AEROSOL
APPARATUS
GENERATOR
AIR FILTER

v Y

SPECIMEN

FIG. 6 APPARATUSFOR SODIUMCHLORIDETEST

1 Glass screw top jar

2 Nozzle
3 Fibre washer
4.5 mm external diameter
2.0 mm internal diameter
0.8 mm thickness
4 sk?eve
5 Stem
6 Rubber gasket
7 Head
8 Rubber gasket
25.0 mm external diameter
10,0 mm internal diameter
1.5 mm thickness
Seals to be airtight
9 Nut
10 Screw cap

FIG. 7 ATOMIZER

12
 .. .
Is 9473:2002

, , 1 1 ,
i r I 1 1
J
I
SIZE DISTRIBUTIONPRODUCEDBY

AT13M171Llm 4., .,. -, -., -. . .- . 1 I I i

, , 1
I I I
, ! I 1 / [i I 4’ 1 1
3 I 1111 I 1 I I ! I HI i
I Ill I I I I I
I 1
I I I I ~
~..~

I=FElzD

0.0’ \ , I 1 I I I I I I I 1 I I I I 1 I I I 1
(h 0.0510.2Q51 2 5 10 20304016070,00 90 95 9899 99.8[ 99.99
0.1 so 99.9
PERCENTAGEBELOW STATEDSIZE %

FIG. 8 PARTICLE SIZE DISTRIBUTION

will not cause an appreciable change in the Sodium chloride particles in air passing through the
characteristics of the test aerosol. flame tube are vaporized giving the characteristic
sodium emission at 589 nm. The intensity of this
The sodium chloride aerosol is analyzed before and after
emission is proportional to the concentration of sodium
the filter under test by flame photometry. The
in the air flow.
photometer used for this analysis can be any suitable
instrument having the required sensitivity, however, a The intensity of the light emitted by the flame is
photometer specially designed to meet these measured using a photomultiplier tube. To separate
requirements is available. The instrument is hydrogen the sodium emission from background light of other
flame photometer. The hydrogen burner is housed in a wavelengths, a narrdw band interference filter with
vertical flame tube which opens at its lower end into appropriate sideband filters is used. This filter should
the sample tube through which the aerosol to be preferably have a half-peak band width of not more
analyzed flows. The flow of aerosol to the flame is than 5 nm.
controlled by convection and is held constant with a
As the photomultiplier output is only proportional to
bleed valve.
the incident light over a relatively small range, high
A small quantity of filtered air is fed continuously into light intensities are attenuated by neutral density
the sample tube downstream of the inlet to the flame filters. These filters are accurately calibrated in
tube. The function of this supply is to prevent room conjunction with the interference filter in use and so
air, which may contain considerable quantities of the actual light intensity can be calculated from the
sodium salts, from reaching the burner when there is output of the photomultiplier. The signal from the
no flow through the sample tube, photomultiplier is amplified and displayed on a meter
or chart recorder,
The hydrogen burner, which gives a flame symmetrical
about the vertical axis, is surrounded by a heat-proof glass Calibration of the flame photometer will depend on
tube. This tube has to be optically homogeneous to the detailed design of the instrument and the
minimize the effect on the light transmitted by the flame. manufacturer’s instructions should be followed if
 . ..

Is 9473:2002

reliable results are to be obtained. In general, however, C, = Sodium chloride concentration after the
the methods which may be used are multiple dilution filter.
of the aerosol dilution of the atomizer solution or a A-4.3 Paraffin Oil Test
combination of both. If aerosol or solutions dilution
is used alone, the lower calibration limit is An aerosol of paraffin oil droplets is generated by
approximately two orders of magnitude higher than atomizing heated paraffin oil. The concentration of
the ultimate sensitivity of the instrument. this aerosol is measured before and after the filter under
test by means of an aerosol photometer. Accurate
Where a photomultiplier with attenuating filters is
determination are possible in the range <0.0003 to
used for detection this is unimportant as the 100 percent filter penetration.
photomultiplier measures a constant range of light
levels over the entire range for the instrument and the A-4.3. 1 Apparatus
values of the attenuating filters are known and The apparatus is shown in Fig. 9. The aerosol is
invariable. Hence, the calibration curve is linear at generated using an atomizer (Fig. 10 and 1l). The
low concentrations and can safely be extrapolated to atomization vessel (6) is filled with paraffin oil
the lower values. The upper limit of linearity of the (paraftinum perliquidum CP 27 DAB 7), so that the
calibration curve is approximately 0.12 mg/m3 due to oil level is between the minimum/maximum-marks
re-absorption of light within the flame. Non-linear (10), The atomization vessel is heated by means of an
calibration is possible above this point up to electric heating device (8), so that the temperature of
approximately 15 mg/m3. Where other detectors are the oil is kept at IOO”Cby means of a thermostat (9).
used, this may not be the case and a combination
The temperature is measured by the thermometer ( I 1).
technique would be required to reach the ultimate
Filtered compressed air at 4 bar (3, 4) is pre-heated
sensitivity.
(8) and blown through the multiple nozzle unit (12
A-4.2.2 Test Conditions and Fig. 11). Large droplets in the generated oil mist
are separated in the control nozzle (13) and in the
Particle size distribution of the test aerosol (see Fig. 8).
spiral tube (15). In the mixing vessel (5), the oil
Flow rate of test aerosol 95 l/rein droplets and oil vapour are diluted with 50 I/rein
Aerosol concentration 8 + 4 mg/m3 filtered air, measured by the flowmeter (2). Since the
Air pressure to atomizer 3.45 + 0.14 bar diluting air is at room temperature, the oil vapour
Flow rate to atomizer 12.75 * 0.25 l/rein condenses in the mixing vessel. The generated aerosol
Flow rate of diluting air 82 1/rein is the test aerosol, which is reduced to the test
Flow rate of hydrogen to concentration of (20 + 5) mg/m3 by wasting an
photometer 450-500 ml/min appropriate fraction of the oil mist (see Fig. 9, item 18
Wavelength of sodium in connection with items 11, 7, 10, 12 and 17) and by
emission 589 nm further dilution with filtered air at a flow rate of
Air temperature ambient 83 l/rein in the blowers actuated by air power (type
Relative humidity <60 percent Friedrichs-Antilinger, see Fig. 9, item 5 and Fig. 12).
The test aerosol produced by this method is polydisperse.
A-4.2.3 Test Procedure The particle size distribution is a logarithmic normal
The test aerosol is fed into the test chamber, where distribution with the median Stokes d~ameterof 0.4 wnl
the filter under test is fixed. A flow of 95 l/rein is (for the number distribution) and the logarithmic
blown through the filter and the aerosol is fed into the standard deviation 0.26 (see Fig. 13).
test chamber, where the filter under test is fixed. A flow The test aerosol is fed into the test chamber [Fig. 9, ( 1)],
of 95 1/rein is blown through the filter and the aerosol where the filter under test is to be fixed (15). The
concentration if measured immediately before and after excess of the aerosol is filtered by a high efficiency
the filter by the photometer. The i~itial penetration filter with a low flow resistance (1O). A flow rate of
shall be measured at 3 + 0.5 min. 95 1/rein is drawn through the filter under test. The
A-4.2.4 Calculation of the Penetration test concentration is measured before and after the filter
under test by means of an integrating light scattering
photometer. The principle of the aerosol photometer
P =~ x 100 percent
is shown in Fig. 14. The instrument is a 45° scattering
I
where photometer, The light source is directed to the
measuring cell and to the photomultiplier. The direct
P = Penetration beam to the multiplier is interrupted by a chopper, so
C, = Sodium chloride concentration before the that the scattered light from the particles is always
filter, and corrected for the source intensity variations. The
14
 ...

Is 9473 :2002

44
16
1 I
I
7
$? r“-

COMPRESSED
AIR
& ‘-v,””,
PUMP

t
I
COMPRESSEII
AIR

IL
14

8
8

1 Test chamber: Rigid transparent material, diameter 10 High efficiency filter with low resistance.
500 mm, height 500 mm, covered with 11 Tee for taking out the amount of oil mist necessary for
plywood on both sides. testing.
2 Tightly fitting door of the chamber. 12 Needle valve controlling the oil mist concentration in
3 Dish for collecting oil running down the walls of the tube. the chamber.
4 Cover for the blowers actuated by air power. 13 011mist generator.
5 Blowers actuated by air power for taking the 14 Aerosol photometer.
concentrated oil mist into the chamber. 15 Connecting pipe to test object.
6 Flowmeters, range 800-8000 I/h 16 Probe for measuring the oil mist concentration in the
a) for measuring the propellent air for the blowers chamber. The aerosol photometer is connected with 15
(5 000 I/h), and or 16 as required by means of a short tube, the
b) for measuring the test flow rate (95 l/rein). connecting pipe not employed is to be closed tightly.
7 Valves controlling the flow rate. The tubes for the oil mist are textile reinforced plastic
8 High efficiency filters. tubes with an inner diameter of 19 mm.
9 Reducing valves, range 1-5 bar at a pre-pressure of 17 Woulfe’s bottle.
6-10 bar. 18 Buffer volume of51.

FIG. 9 APPARATUSFOR PARAFFINOIL TEST

reference beam is attenuated by means of neutral density c) Aerosol concentration 20 * 5 mg/m3

filters and of a neutral densi~ wedge automatically ~o -‘
d) Air temperature ambient
the intensity of the scattered light beam.
e) Air pressure to atomizer 4+0,15 bar
The intensity of the scattered light, which is a measure
for the aerosol concentration, is displayed. o Flow rate to atomizer 13.5 ● 0.5 l/rein

A-4.3.2 Test Conditions g) Mixing air flow rate

in aerosol generator 50 l/rein
a) Particle size distribution of the test aerosol h) Flow rate of diluting air 83 l/rein
(see Fig. 13).
b) Flow rate through the j) Temperature of the oil between 100 and
in the generator 11O”C
fiher under test : 95 l/rein

15
 .....

Is 9473:2002

15

160

‘~ ‘MEASURtNG
17

1 Bar air inlet with airfilter 12 Atomization nOZZIe

2 Flowmeter 13 Control nozzle
3 Pressure reducer 14 U-tube manometers
4 Mmometer 15 Spiral tube
5 Mixing vessel 16 Drainage screw
6 Atomization vessel 17 Outlet to measuring device
7 Thermostat vessel 18 Waste outlet
8 Heating jacket 19 Change-over valve
9 Thermostat 20 Oil pump
10 Oil-level indicator 21 CM supply container
11 Thermometer 22 Locking screw

FIG. 10 GENERATOR
FORPARAFFIN
OIL AEROSOL

A-4.3.3 Test Procedure where

The test aerosol is fed into the test chamber, where P= Penetration,
the filter under test is fixed. A flow rate of 95 l/rein is I, = Photometer reading before the filter,
sucked through the filter by means of a suitable pump.
12 = Photometer reading after the filter, and
The aerosol concentration is measumd immediately
10 = Photometer zero reading for clean air.
before and after the filter by the aerosol photometer.
The initial penetration shall be measured at A-5 FLAMMABIL~~Y
3 * 0.5 min.
A-5.1 A total of 4 filtering half masks shall be tested;
A-4.3.4 Calculation of the Penetration 2 as received and 2 afler temperature conditioning in
accordance with A-1.2.
I –I.
P=~ x 100 percent
[, – 10

16
 Is 9473:2002
.
-—

-l-i-

MAX.
OIL LEVEL

MIN

“x-d-l=- ,DIA
‘ETA’L
MULTIPLENOZZLEUNITtTEM
PARAFFINOILZ

All dimensions in millimetres.

FIG. 11 ATOMIZER

A-5.2 The filtering half mask shall be tested for d) For the test, the filtering half mask shall be
flammability as per Annex E of IS 14166, but using passed once through the flame at 6 + 0.5 cmls.
only one burner and with the following variations: When components such as valve(s), etc are
arranged on other parts of the filtering half
a) For the test the filtering half mask shall be
mask, the test shall be repeated with other
put on the metallic dummy head which shall
samples of the filtering half mask in the
be motorized such that it can describe a
appropriate position.
horizontal circle with variable control speed.
The head shall pass over a Bunsen propane A-6 CARBON DIOXIDE CONTENT OF THE
burner whose position can be adjusted by INHALATION AIR
means of suitable gauges, the height of the
flame shall be set to 40 mm and the distance A-6.1 A total of 3 filtering half masks shall be tested,
between the top of the burner and the lowest all 3 as received.
part of the filtering half mask passing the A-6.2 The apparatus consists essentially of a breathing
filtering half mask through the flame shall machine with solenoid valves controlled by the
be set to 20 mm. breathing machine, a connector, a C02 flow meter, a
b) The head shall be set in motion and the effect C02 analyzer and a humidifier.
of passing the filtering half mask through the
The apparatus subjects the filtering half mask to a
flame shall be noted.
respiration cycle by the breathing machine.
c) The temperature of the flame at a height of
20 mm above the burner tip shall be For this test, the filtering half mask shall be fitted
‘1
800 * 50°C. The temperature shall be securely in a leak-tight manner but without
checked with a suitable measuring deformation to the dummy head (type Sheffield)
instrument. (see Fig. 15).

17

\,\
Is 9473:2002

Air shall be supplied to it from a breathing machine

adjusted to 25 cycles/rein and 2.0 l/stroke and the
exhaled air shall have a carbon dioxide content of
* 5 percent by volume.

K
A typical test arrangement is shown in Fig, 16.
If the design of the test equipment causes a C02 build
o
u-lI 1
I
up, a COZ absorber shall be used in the inhalation
branch between solenoid valve and breathing machine.
The CO, is fed into the breathing machine via a control
valve, a-flow meter, a compensating bag and two non-
retum valves.
Immediately before the solenoid valve a small quantity
of exhaled air is preferably continuously withdrawn
through a sampling line and then fed into the exhaled
air via a COZ analyzer.
To measure the COZ content of the inhaled air,
5 percent of the stroke volume of the inhalation phase
of the breathing machine is drawn off at the marked
place by an auxiliary lung and fed to a COZ analyzer.
The total dead space of the gas path (excluding the
A breathing machine) of the test installation should not
exceed 2000 ml.
The COZcontent of the inhaled air shall be measured
and recorded continuously.

A-6.3 Test Conditions

Ambient
atmosphere : laboratory ambient
Exhalation air : 37 + 2°C, >95 percent
relative humidity

I 492
-J
fblo —
Air flow ftom
the front
For test
: 0.5 m/s

-1 arrangement : see Fig. 17

This test shall be performed until a constant carbon
A-A dioxide content in the inhalation air is achieved.
,
A-7 STRENGTH OF ATTACHMENT OF
EXHALATION VALVE HOUSING
A-7.1 A total of three filtering half masks shall be
tested. One as received, one temperature conditioned
in accordance with A-1.2 and one after the test
described for mechanical strength in A-10.
A-7.2 The filtering half mask shall be mounted
securely to a fixture as shown in Fig. 18. An axial
tensile force of 10 N shall be applied to the valve
(housing) for 10 s. The results shall be noted.
“{
All dimensions in millimetres.
A-8 BREATHING RESISTANCE
FIG. 12 BLOWERS ACTUATEDBY AIR POWERS
A-8.1 Test Samples and Fixture
A total of 9 filtering haif masks shall be tested; 3 as
18
 -. .

Is 9473:2002

99.5 “
‘/0
98
95
90
80
70
PARAFFINOIL MIST
kJ x NUMBERDISTRIBUTION
; 40
~ 30
& 20
: 10
g5
5
52
n 1
0.5 -
0.2
0.05-
, I , 1, , , * , I t., , t , t t ,4
10-2 2 3 L567810-’ 2 34567810° 2 3 456pm10’
STOWS DIAMETERIN km

FIG. 13 PARTICLE SIZE DISTRIBUTIONOF PARAFFINOIL MIST

PHOTO
BEAM REGULATOR MULTIPLIER
la DIRECT LIGHT BEAM ,—

REGULATINGMOTOR

\ I SCATTEREDLIGHT

BEAM

L
AMPLIFI

‘LIGHT SOURCE \
MEASURINGCHAMBER

FIG. 14 SCHEMEFOR THEAEROSOL PHOTOMETER

19
1s 9473:2002

m
,.” -

P
--
f=
&‘1’ 0 /-.

x INSERT FOR MEASUREMENT

OF BREATtilNG RESISTANCE
2

200
tr 7
, 1

u-l
m

- —- —.— .—. —. .—. — .—.

4-

6
b
- EXHALATION

Alldimensions in millimetres

FIG. 15 DUMMY HEAD (SHEFFIELD HEAD) FOR CARBON DIOXIDE CONTENTTEST OF THE
INHALATIONAIR (DEAD SPACE)FORA FILTERINGHALF MASK

received, 3 after temperature conditioning in A-8.4 Correction

accordance with A-1.2, and 3 after the simulated The resistance value shall be corrected to 27°C and
wearing treatment as described in A-1.l. 1 bar absolute.
The filtering half mask shall be fitted securely in a
A-9 CLOGGING
leak tight manner but without deformation to the
dummy head (type Sheffield). The test aerosol shall be dolomite or coal. A total of 3
filtering half masks shall be tested. One as received
A-8.2 Exhalation Resistance and two after temperature conditioning in accordance
with A-1.l.
The filtering half mask shall be sealed on the dummy
A-9.1 Clogging Test Using Coal
head (type Sheffield). The exhalation resistance shall
be measured at the opening for the mouth of the A-9.1.1 Principle
dummy head using the adaptor shown in Fig. 15 and The test consists of drawing dry, dust laden air through
a breathing machine adjusted to 25 cycles/rein and a a filtering half mask on the inhalation cycle of a
2.0 I/stroke or a continuous flow of 160 l/rein. A sinusoidal breathing machine and blowing moist, dust
suitable pressure transducer shall be used. free air through the filtering half mask during the
exhalation cycle and determining the pressure drop
A-8.3 Inhalation Resistance
across the filtering half mask following the collection
The inhalation resistance shall be tested at 30 and of 1.5 g of dust. The test shall be conducted with the
95 l/rein continuous flow. inhaled air at an ambient temperature of 27 + 2°C and
20

\\\
 -.

Is 9473:2002

1 Breathing machine 6 Carbon dioxide analyzer

2 Auxiliary lung 7 Sokmoidvalves
3 Non-return valve 8 Dummyhead
4 Flowrneter 9 Sampling tube forinhalation air(see Fig. 17)
5 Compensator 10 Carbon dioxide absorber
11 Humidifier

FIG. 16 SCHEME OF TYPICAL TEST RIG FOR CARBONDIOXIDE CONTENTOF THE INHALATIONAIR

DUMMY H

:,6
SENSORFOR
AIR FLOW
D.3 TO Oo5m DUCT
%’

I J TOWARDSTHE

Y
. -- -- BREATHING
-
b
MACHINE

2m 0.25m
BLOW

FIG. 17 SCHEME OF TEST ARRANGEMENTANDAIR FLOW FORCARBONDIOXIDETEST

at 65 + 5 percent relative humidity and the exhaled For measuring the pressure drop and setting up flow
air at 37 + 2°C and 95 percent relative humidity through nozzle A, valve X is set at CALIBRATE;
minimum. during these operations, the breathing machine is
A-9.1.2 Test Equipment switched off. For testing the valve is set at TEST. For
determining the quantity of dust which shall be
A scheme of a typical apparatus is given in Fig. 19.
introduced into the hopper H in order that 1.5 g be
The double acting breathing machine B (2 I/stroke,
15 cycles/rein) and the critical orifice O in conjunction collected on the filtering half mask, valve Y is set at
maintain the flow rate through mixing chamber C and CALIBRATE; at this setting the flow rate during
nozzle A essentially constant at 95 l/rein and exhalation is zero.
9.5 l/rein respectively throughout the sinusoidal
A-9.1.3 Test Conditions
breathing cycle, so ensuring dust conditions within
the chamber C. The dust used for the clogging test shall be coal dust
Is 9473:2002

w 1“
i ION FORCE

FIG. 18 FIXTURE FOR FACE BLANK

AIR SUCTION

‘J/k
ONE-WAYVALVE
VALVEPOStTKJN

VALVEY* TEST
DOUBLEACTING
BREATHING
MACHINE,B VALVEYb

VALVEYa

-’w!i $

II
VALVEYb

CALIBRATE

HYGROMETER I.VEXb

$ VALVEYa

VALVEYb

TEST

VALVEXb

++-
VALVEXa
HYGROMETER MIXING
CHAMBERC CALIBRATE
HOPPERH
7P 1“ NOZZLEA VALVEXb

w TURNTABLE T
++
‘VALVEXa

FIG. 19 TYPICAL SINUSOIDALDUST CLOGGINGTEST APPARATUSFOR VALVELESS FILTERINGHALF MASKS

22
 ...

.
Is 9473:2002

ground by ball mill and graded by sieving, the portion A-9.2 Clogging Test Using Dolomite Dust
which passes a 240 mesh (60 micrometre aperture)
A-9.2.1 Principle
sieve being used for the test. The size distribution of
coal dust is given in Table 5. The test consists of subjecting the filtering half mask
to a sinusoidal breathing simulation. The sample is
Table 5 Size Distribution of Coal Dust surrounded by a known concentration of dolomite dust
(Clause A-9. 1.3) in air. Following the exposure, the breathing resistance
and the filter penetration of the sample filtering half
S1No. Coulter Counter Sedimentation Analysis mask are measured.
~ ~
Percent weight A-9.2.2 Test Equipment
(Equivalent number (Stokes
spherical particles diameter) A scheme of a typical apparatus is given in Fig. 20.
diameter) oversize The working area of the test chamber has a suggested
(No. >2.5 ym
=100) square section of 650 mm x 650 mm. The breathing
~m machine has a displacement of 2 l/stroke. The exhaled
(1) g (3) (4) (5) air shall pass a humidifier in the exhaled air circuit,
O 2.5 100 2.5 89.0 such that the exhale air temperature, measured at the
ii) 3.0 65 3.0 87.5
iii) 5,0 27 5.0 80.5
position of the sample filtering half mask is 37+ 2°C
iv) 7,6 14.6 7.0 77,0 and 95 percent relative humidity minimum,
v) 10.0 7.7 10.0 65.0
vi) 15.0 3.5 15.0 52.5 A-9.2.3 Test Conditions
vii) 20.0 1.9 20.0 36.0
viii) 25.0 1,1 25.0 31.2 a) DUST:DRB 4/15 dolomite. The size
ix) 30.0 0.6 30.0 23.2 distribution of dolomite dust is given in
x) 35.0 0.3 35.0 15,7 Table 6.
xi) 40.0 0.2 40,0 9.3 b) The particle size distribution of the air borne
dust at the working area of the dust chamber
A-9. 1.4 Test Procedure is given in Fig. 21. This characteristic is an
The test apparatus shall be setup connecting a weighed essential parameter, which shall be verified
filtering half mask into the air circuit at the top of especially if the geometry of the test chamber
chamber C. Valve X shall be set to CALIBRATE and is somewhat different from the model
air shall be drawn through the filtering half mask at described in this standard.
95 l/rein; valve E shall be adjusted until the flow c) Continuous flow through the dust chamber:
through the nozzle A is 9.5 l/rein. Valve X shall then 60 m3/h, linear velocity 4 cmls.
be set to TEST and valve Yto CALIBRATE, a known d) Sinusoidal flow through the filtering half
weight of dust shall be fed into the hopper H and mask is delivered by a breathing machine
dispersed into the chamber. After dispersal, the adjusted to 15 cycles/rein and 2.0 I/stroke;
filtering half mask shall be re-weighed. A number of the exhaled air shall be saturated in humidity.
filtering half masks shall be exposed until the weight
e) Concentration of the
of dust which shall be introduced into the hopper to
dust : 400+ 100 mg/m3
give a 1.5 g collection is determined.
f) Temperature of the air : 27+ 2“C.
Connect the filtering half mask into the chamber. Valve
d Relative humidity of
Y shall be set to TEST, the previously determined
the air : 45 + 15 percent
weight of dust shall be introduced into the hopper H
h) Testing time : Until the product of measured
and after allowing the filtering half mask to reach
dust concentration and exposure time is
equilibrium the dust shall be dispersed into chamber C.
833 mg h/m3 or until:
After dispersal valve X shall be set to CALIBRATE
and the breathing machine turned off. The pressure 1) for valved filtering half masks, the peak
drop across the filtering half mask at 95 l/rein shall inhalation resistance (corresponding to
be read off manometer M. a continuous flow of 95 l/rein) has
reached 4 mbar for class FFP 1 or 5 mbar
Repeat the test on the other two samples and report
for class FFP2 or until the peak
the 3 recorded pressure drops. After completion of the
exhalation resistance has reached 1,8
clogging test, the filtering half masks shall be allowed
mbar (corresponding to 3 mbar at a
to stabilize in the laboratory for 24 h at the end of
continuous flow of 160 l/rein); and
which the filtration efficiency of each filtering half
mask shall be determined. 2) for valveless filtering half masks, the

23

_.,
 . ..-

.
Is 9473:2002

DUSTTEST CHAMBER
FILTER PUMP
lNJ~ToR _
PROFtE L _- mnn
I
D~ST ,Ap

7“ $- :-o “
SFECIMEN EXHAUST
COMPRESSED I FLOW
AIR AIR I
FILTER METER
c PROBE LINE
T 1
DUST
DISTRIBUTOR PUMP
I
I t I COUNTER

~ ~ ‘XHAUST

mw

HUMIDITY
d 1

FIG. 20 TYPICAL SINUSOIDALDOLOMITEDUST CLOGGINGTEST APPARATUS

I

peak inhalation resistance or the peak filtering half mask shall be measured using clean air.
exhalation resistance has reached 3 mbar The filter penetration shall then be measured in
for class FFP1 or 4 mbar for class FFP2. accordance with A-10.
NOTE — 833 mg h/m3correspondsto inhaling a total volume of
air laden with 1.5g of dust. This is represented, for example, by a Table’6 Size Distribution of Dolomite Dust
dust concentration of 400 mg/mj and an exposuretime is 125 min.
(Clause A-9.2.3)
Because of the dust losses on exhalation the cumulative weight of
dust collected on the filtering half mask will probably be less than
1.5g. For this reason, there is no purpose in weighing the sample SI No. Coulter Counter Sedimentation Analysis
tiltering half mask. ~ ~
Percent weight
(Equivrdent number (Stokes oversize
A-9.2.4 Test Procedure
spherical particles diameter)
Dust from the distributor shall be conveyed to the dust diameter) oversize
(No. > 2.5pm
chamber where it shall be dispersed into the air stream =100)
of 60 m3/h. ~m pm
The sample filtering half mask shall be fitted in a leak (1) (2) (3) (4) (5)
tight manner to a dummy head or a suitable filter 0 0.7 100 1 99.5
ii) 1 80 2 97.5
holder located in the dust chamber. The breathing
iii) 2 30 3 95
machine and humidifier shall be connected to the iv) 3 17 5 85
sample and shall be operated for the specified testing v) 5 7 8 70
time. . 10 50
vi) 9 2 12 26
The concentration of dust in the test chamber maybe 14 10
measured by drawing air at 2 l/rein through a vii) 12 1 18 1
sampling probe equipped with a pre-weighed, high
efficiency filter (open face, diameter 37 mm) located A-10 MECHANICAL STRENGTH
near the test sample as shown in Fig. 22.
A-10.1 Apparatus
The dust concentration shall be calculated from the
The apparatus, as shown schematically in Fig. 23,
weight of dust collected, the flow rate through the filter
and the time of collection. Other suitable means may consists of a steel case (K) which is fixed on a vertically
be used. moving piston (S), capable of being lifled up 20 mm
by a rotating cam (N) and dropping down onto a steel
A-9.2.5 Assessment of Clogging plate (P) due to its own mass as the cam rotates. The
Following the exposure the breathin} resistance of the mass of the steel case shall be more than 10 kg.

24

\
 Is 9473:2002

A-10.2 Procedure prior to the performance testing. The test rig shal I be
operated at the rate of approximate y 100 rotations/rein
A-10.2. 1 The filters shall be treated as received,
for approximately 20 min and a total of 2000 rotations.
removed from their packaging but still sealed. The filter
shall be placed on their sides in the case (K) so that A-1 1 VISUAL INSPECTION
they do not touch each other during the test, allowing
The visual inspection is carried out where appropriate
6 mm horizontal movement and free vertical movement.
by the test station prior to laboratory or practical
A-10.2.2 After the test any loose material that may performance tests. The visual inspection includes
have been released from the filter shall be removed marking and instructions for use.

99,99
‘/0
1[ 99.9
I 99.5

M
: 95
g Xl
DOLOMITEDRS 4/15 TEST AEROSOL
G 80
3
~ 70
# 60
w 50
g Lo
s 30
g 20
~ 10
5
2
1
0.5
0.2
0.05-
,. u
0.01
2 3 b557810 20 30 LO 60 pm100
PARTICLE- DIAMETERMASS BASIS II m -

FIG. 21 PARTICLE SIZE DISTRIBUTIONOF DOLOMITEDUST IN THE TEST CHAMBER

25

\
‘,,
 ...
IS 9473:2002

OPENNING
N
DUSTCHAMBER
K16S9 ,

Ill 1s5 I
Soo
“4-l- RECOMWNDED PROBEPOSITION

METHYL
DUMMYHEADADAPTER METHACRYLATE

H60xI

—z
~ Jpg I
1
R.--667 ~
DUMMYHEADCONFWJRATIDN
DuM~ HEAOFILTERHOUER
FOR REMOVALOF PARTICLESPENETRATING
THROUGHTHE FILTER

All dimensions
in millimetres.

FIG. 22 DETAILS OF TYPICALDOLOMITEDUST CLOGGINGTEST APPARATIJS

26

\
I.
 1s 9473:2002

.
1
/

Ezzz ,

s’
N
=+-

All dimensions in millimetres.

FIG.23 TEST EQUIPMENTFOR TEST OF MECHANICALSTRENGTH

‘1

27
 r
._——

1s 9473:2002

ANNEX B
(Foreword)
COMMITTEE COMPOSITION

Industrial Safety and Chemical Hazards Sectional Committee, CHD 8

Organization Representative(s)
National SafelyCouncil, Mumbai Smu K. C, GUPrA
(C/rahrrurr)
Airports Authority of India, New Delhi REPRESENTAW
Atomic Energy Regulatory Board, Mumbai Smu P.K. GHOSH
13habhaAtomic Research Centre, Mumbai DRB. N. RATHL
Central Boiler Board, New Delhi REPRESENrATWE

Century Rayon, Thane %0 H. G. UH,4h4Clim0AN

Smrr S. K. MIssw (A[ternafe)
Central Leather Research Institute, Chennai REFRE?ENrATIVE
Central Mining Research Institute, Jharkhand Smr J, K. PANDEY
Central Warehousing Corporation, New Delhi klWiENrAllVFi

Confederation of Indian Industries, New Delhi REFiWSENrA71VE

Department of Explosives, Nagpur REPRSS13WA~

Department of Industrial Policy& Promotion,New Delhi DR D, R, CHAWLA

Development Commissioner (SS1),New Delhi REQRJ3ENrATNS

Directorate General of Health Services, New Delhi REPRFSENrAIIVE

Directorate General Factory AdviceServices andLabourInsthutes, DRA,K, Mmmm.m
Mumbai StmuS. P. RANA(Mfernafe)
~irectoratcot’industrial
SafetyandHealth(FactoryInspectorate), REPRESENrAIWE
Mornabai
Directorate
GeneralofMinesSafety,Dhanbad OFMINESSmw
DIRECTOR (MSE)
DEPUTYDIRECTOR
OFMINESSmmv (HQ)
(Alternate)
Employees Slate Insurance Corporation, New Delhi REPRESENTATIVE

Excel [odustries Limited, Mumbai REPRESENrATIVS

Ilindustan Aeronautics Limited, Bangalore RSPRESEiWATTVE

I{industm Lever Limited, Mumbai Smu B. B. DAVE

SHRIADITYAJmv.m (Ahemare)

Indian lnstitotc of Chemical Technology, Hyderabad %0 S. VENXATESWARA RAO

lndian Chemical Manufacturers Association, Mumbai Smu V. N. DAS
!ku A. A. PANJWANI
(Alternate)
[ndian Drugs and Pharmaceuticals Limited, Rishikesh REPRESENTATIVE

Indian PctrochernicalCorporation Limited, Vadodara %+ P, VIJAYRAGHAVAN

(Alternate I)
SHSUM. R. PATEL
SmuA. V, S,-uwmv(Alternate 11)
Indian Space ResearchOrganization, Sriharikota Smu P.N. SAmm,m
Smw V. K. SRNASTAVA(Alternate)
IndustrialToxicology Research Centre, Lucknow DRVrrumrxuMrsru
DRV.P. Srrmwm (Alternate)
Ministry of Defence (DGQA), New Delhi Smu M, S. SULTANIA
Smu SurmGHOSH(Alternate)
Ministry of Defence, Directorate of Standardization,New Delhi Smo P. S. AHUJA
SINGH(Alternate)
LT-COL TSIINDER

Ministry of Defence (OFB), Kolkata DRD. S. S, GANGULY

SsrraR. SRINIVASAN
(Alternate)
Ministry of Defence (R & D), Kanpur DRA. K. SAXENA
DRRA~DRASINGH
(Akernafe)

(Continued on page 29)

28
 Is 9473:2002

(Con/inuedfrom page 28)

Organization Representative(s)

Ministry of Environment& Forest, New Delhi &WiEtWAIWE

National Institute of Occupational Health, Ahmedabad REfRESi3WAllW

National Organic Chemical Industries Limited, Thane Dr+B. V. BAPAT

Sm V. R. Nm (Alternate)
National Safety Council, Mumbai SmrrP. M.lUo
SmuD. BISWAS(Alternate)
Oil Industry Safety Directorate, New Delhi Srca S. K. CnuawBmn
SmrrV. K, SRIVASTAVA
(Alternate)
Safety Appliances Manufacturers Association, Mumbai
Standing Fire Advisory Council, New Delhi
Steel Authority of India Limited, Rarrchi
SIEL Chemical Complex, New Delhi
Southern Petrochemical IndustriesCorporation Limited, Tuticorin SmtrV.JAYARAMAN
Smr S. MURUGANANOAM
(Alternate)
Tata AIG Risk Management Services Limited, Mumbai Smu URMISHD. SW
BIS Director General Sm S, K, CrwuDmm.r,
Dhector & Head (CHD)
[RepresentingDirector General (Ex-oficio)]
Member Secretaq
SmuN. K.P.m
Dhector (CHD), BIS

29
 ..

Bureau of Indian Standards

BIS is a statutory institution established under the Bureau ofhiian Standards Act, 1986 to promote harmonious
development of the activities of standardization, marking and quality certification of goods and attending to
connected matters in the country.

Copyright

BIS has the copyright of all its publications. No part of these publications may be reproduced in any form
without the prior permission in writing of BIS. This does not preclude the f~e use, in the course of implementing
the standard, of necessary details, such as symbols and sizes, type or grade designations. Enquiries relating to
copyright be addressed to the Director (Publication), BIS.

Review of Indian Standards

Amendments are issued to standards as the need arises on the basis of comments. Standards are also reviewed
periodically; a standard along with amendments is reaftlrmed when such review indicates that no changes are
needed; if the review indicates that changes are needed, it is taken up for revision. Users of Indian Standards
should ascertain that they are in possession of the latest amendments or edition by referring to the latest issue of
‘BIS Catalogue’ and’ Standards: Monthly Additions’.
This Indian Standard has been developed from Dot: No. CHD 8 (827).

Amendments Issued Since Publication

Amend No. Date of Issue Text Affected

BUREAU OF INDIAN STANDARDS

Headquarters:
Manak Bhavan, 9 Bahadur Shah Zaf~mMarg, New Delhi 110002 Telegrams: Manaksanstha
Telephones: 3230131, 3233375,3239402 (Common to all oftices)
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