GB 30864-2014 (GB30864-2014)

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GB 30864-2014: PDF in English
GB 30864-2014
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
ICS 13.340.30
C 73
Respiratory Protection -
Powered Air-purifying Respirator
ISSUED ON: 2014-07-24
IMPLEMENTED ON: 2015-06-01
Issued by: General Administration of Quality Supervision, Inspection and
Quarantine;
Standardization Administration of PRC.
Table of Contents
Foreword ... 4 
1 Scope ... 5 
2 Normative References ... 5 
3 Terms and Definitions ... 6 
4 Classification and Labelling ... 11 
4.1 Classification and Labelling of Powered Air-purifying Respirator (PAPR) .. 11 
4.2 Classification, Labelling and Tinting of PAPR Filter Elements ... 11 
5 Technical Requirements ... 14 
5.1 General Requirements ... 14 
5.2 Tight-fitting Facepiece ... 15 
5.3 Loose-fitting Facepiece and Loose-Fitting Hood ... 16 
5.4 Manufacturer’s Minimum Design Flow Rate (MMDF) and Manufacturer's
Design Duration ... 17 
5.5 Respiratory Resistance ... 17 
5.6 Visor... 18 
5.7 Inward Leakage ... 19 
5.8 Breathing Hose ... 20 
5.9 Dead Space ... 20 
5.10 Filter Element ... 20 
5.11 Strength of Connecting Component ... 23 
5.12 Noise ... 23 
5.13 Flammability ... 23 
5.14 Checking Device ... 24 
5.15 Warning Device ... 24 
5.16 Intrinsic Safety and Electrical Part ... 24 
5.17 Mass ... 25 
5.18 Practical Performance ... 25 
5.19 Requirements for Fire-fighting PAPR ... 25 
5.20 Information to be Provided by the Manufacturer ... 26 
6 Test ... 28 
6.1 Samples and Ambient Conditions of Test ... 28 
6.2 Visual Checking ... 28 
6.3 Pretreatment ... 28 
6.4 Actual Flow Rate and Manufacturer's Design Duration ... 29 
6.5 Respiratory Resistance ... 34 
6.6 Visual Field ... 35 
6.7 Mechanical Strength of Visor ... 36 
6.8 Inward Leakage ... 36 
6.9 Compression Resistance of Breathing Hose ... 40 
6.10 Dead Space ... 41 
6.11 Filter Efficiency ... 42 
6.12 Protective Time ... 43 
6.13 Resistance of Multiple Filter Elements ... 45 
6.14 Interactive Flow Rate of PAPR with Tight-fitting Facepiece ... 45 
6.15 Tensile Strength ... 49 
6.16 Noise ... 49 
6.17 Flammability ... 50 
6.18 Mass ... 52 
6.19 Practical Performance ... 53 
7 Identification ... 54 
7.1 Identification Content ... 54 
7.2 Identification Location ... 55 
Annex A (Normative) Test Methods for Electrical Insulation and Heat
Resistance of Respirator Facepiece or Hood for Welding Protection ... 56 
Annex B (Informative) Application of Warning Device ... 58 
Annex C (Informative) Description on PAPR Application in Fire-fighting ... 60 
Annex D (Informative) Summary of Requirements for Test Sample ... 63 
Annex E (Normative) Assembly Method of Loose-fitting Hood (with Neck
Sealing Design) with or without Head Fixing Device ... 67 
References ... 71 
Respiratory Protection -
Powered Air-purifying Respirator
1 Scope
This standard specifies the classification, labelling, technical requirements, test methods
and identification of powered air-purifying respirators.
This standard is applicable to powered air-purifying respirators preventing particles, toxic
and harmful gas or vapor.
This standard is not applicable to respirators used in combustible, explosive and
oxygen-deficient environment and for escaping.
2 Normative References
The following referenced documents are indispensable for the application of this
document. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including amendments) applies.
GB/T 2428 Head-face Dimensions of Adults
GB 2626-2006 Respiratory Protective Equipment - Non-powered Air-purifying
Particle Respirator
GB 2811-2007 Safety Helmet
GB 2890-2009 Respiratory Protection - Non-powered Air-purifying Respirators
GB/T 3609.1-2008 Occupational Eye and Face Protection - Welding Protection - Part
1: Welding Protector
GB/T 3609.2-2009 Occupational Eye and Face Protection - Welding Protection - Part
2: Automatic Welding Filter
GB/T 3785.1-2010 Electroacoustics - Sound Level Meters - Part 1: Specifications
GB 3836.1-2010 Explosive Atmospheres - Part 1: Equipment - General
Requirements
GB 3836.4-2010 Explosive Atmospheres - Part 4: Equipment Protection by Intrinsic
Safety "i"
GB/T 5703 Basic Human Body Measurements for Technological Design
GB 12476.4-2010 Electrical Apparatus for Use in the Presence of Combustible Dust -
Part 4: Protection by Intrinsic Safety “iD”
GB/T 12903-2008 Personal Protective Equipment - Terminology
half facepiece
the tight-fitting facepiece capable of covering mouth and nose, or covering mouth, nose
and lower jaw.
[GB 2626-2006, as defined in 3.8]
3.6
full facepiece
the tight-fitting facepiece capable of covering mouth, nose, eyes and lower jaw.
[GB 2626-2006, as defined in 3.9]
3.7
loose-fitting facepiece
the loose-fitting air introduction unit used for positive pressure respirator, which only
covers eyes, nose and mouth and tightly fits with face in part.
Note: as defined in 5.2.2.1 of modified GB/T 12903-2008.
3.8
loose-fitting hood
the loose-fitting air introduction unit used for positive pressure respirator, which is able to
completely cover head, neck and part of the shoulder or is used together with protective
clothing.
Note: as defined in 3.1.12 of modified GB/T 18664-2002.
3.9
breathing hose
the airtight air-guide hose which can deliver the breathing air to facepiece or hood.
3.10
head harness
gas and (or) vapor in air.
3.17
Filter efficiency
the percentage of particles filtered by filter element under specified test conditions.
[GB 2626-2006, as defined in 3.16]
3.18
protective time
the time from the test medium's passing through the filter element to the penetrating
concentration of such test medium reaching the limit value under specified conditions.
Note: as defined in 5.3.2 of modified GB 12903-2008.
3.19
manufacturer’s minimum design flow rate; MMDF
the minimum flow rate promised by the manufacturer to ensure that the respirator meets
corresponding performance requirements.
3.20
manufacturer's design duration
the continuous service time promised by the manufacturer to ensure that the flow rate of
powered respirator is not less than the manufacturer’s minimum design flow rate.
3.21
actual flow rate
the flow rate generated by powered air-purifying respirator measured under specified
conditions.
3.22
interactive flow rate
Filter elements are classified as follows:
a) Type P: prevention against particles;
b) Type A: prevention against certain organic vapor with boiling point higher than
65℃ as specified by the manufacturer;
c) Type B: prevention against certain inorganic gas specified by the manufacturer;
d) Type E: prevention against certain acid gas specified by the manufacturer;
e) Type K: prevention against ammonia and certain organic derivative of ammonia
specified by the manufacturer;
f) Type NO: prevention against nitrogen oxide;
g) Type Hg: prevention against mercury vapor;
h) Type CO: prevention against carbonic oxide gas;
i) Type AX: prevention against certain organic vapor with boiling point not higher than
65℃ as specified by the manufacturer;
j) Type SX: prevention against certain special compound specified by the
manufacturer;
k) Any combination of the above types.
4.2.2 Labelling and tinting of filter elements
Filter efficiency of particle filter element and combination filter element against particles is
classified into two grades: 95.00% and 99.97%, respectively corresponding to labels of
P95 and P100. Gas and/or vapor filter elements of Types A, B, E and K are classified into
three grades according to protective capacity: Grade 1 represents low protective capacity,
Grade 2 represents moderate protective capacity, and Grade 3 represents high protective
capacity; gas and/or vapor filter elements of other Types (e.g. SX, CO, AX, NO, etc.) are
not graded. The classification method of Types A, B, E and K in combination filter
elements is the same as the grading method of separate protective filter elements; see the
last row of the labelling example in Table 2. See Table 2 for labelling, tinting and prevented
pollutant examples of various filter elements of PAPR.
5 Technical Requirements
5.1 General Requirements
The material and structural design used for PAPR shall meet the following requirements,
checked according to the method in 6.2 and assessed according to 6.19.
a) The material shall meet the following requirements:
1) Suitable for use under the expected exposure temperature and humidity
conditions and corrosive environment; after the pretreatment under the
conditions specified in 6.3.1, PAPR components (except filter element) shall
be free from obvious deformation and inside separation and shall meet the
requirements of 5.2~5.9 and 5.11~5.18;
Note: generally, the pretreatment doesn't cover charger unless the respirator design
makes the battery charger inseparable from the respirator.
2) Materials known to be able to cause skin irritation or other adverse reactions
shall not be adopted for components which may directly contact the wearer's
skin;
3) The product is able to withstand the detergent and disinfectant and their
treatment methods as suggested by the manufacturer;
4) The inside of filter element shall be able to withstand the corrosivity of filter
medium;
5) The air flow filtered by filter element shall be free from substance or peculiar
smell harmful to human.
b) The structural design of product shall meet the following requirements:
1) It shall not cause structural damage easily; the component design,
composition and installation shall not endanger the wearer;
2) The head harness and PAPR fixing device shall be adjustable and convenient
for wearing and removal; the PAPR shall be firmly fixed on the wearer, and no
obvious pressing or pain due to pressing shall appear during wearing.
3) During the wearing and removal process, the part directly contacting the
wearer shall be free from any sharp edge and burr;
2890-2009.
5.2.2 Head harness
The head harness strength shall meet the requirements of 5.1.11, GB 2890-2009.
5.2.3 Negative pressure PAPR
Tight-fitting facepiece used for negative pressure PAPR shall meet the following
requirements:
a) It shall meet the requirements of 5.5, 5.7, 5.11 and 5.12, GB 2626-2006;
b) Where checked according to the method in 6.2, the tight-fitting facepiece used for
negative pressure PAPR shall only be used in conjunction with particle filter
element; gas and/or vapor filter element and combination filter element shall not
be used.
5.3 Loose-fitting Facepiece and Loose-Fitting Hood
5.3.1 General Requirements
Product design shall meet the following requirements:
a) Where facepiece or hood doesn't contain fan component, the filter element cannot
be directly connected with facepiece or hood. It is checked according to the method
in 6.2;
b) The facepiece or hood shall be equipped with facepiece or hood as required so as
to be fixed on body; its design and composition shall provide proper fastening
strength and shall be adjustable or have certain flexibility so as to be suitable for
head-form and body type within certain range. It is assessed in 6.19;
c) If the product is claimed to have additional protective functions for eyes, face and
head beyond this standard (e.g., protection against mechanical shock or
non-ionizing radiation, etc.), such additional functions shall not interfere the
respiratory protection performance specified in this standard. It is assessed in 6.19.
5.3.2 Safety helmet function
If the facepiece or hood is claimed to have safety helmet function, it shall meet the
requirements of impact absorption performance (4.2.1), penetration resistance
performance (4.2.2) and chin strap strength (4.2.3) in GB 2811-2007. If used in flammable
and explosive environment, the safety helmet should comply with the requirements of
a) Where tested according to the method in 6.5.2, the peak inhalation resistance of
PAPR under power-off state shall not exceed 1100Pa;
b) Where tested according to the method in 6.5.3, the peak inhalation resistance of
PAPR under power-on state shall not exceed 350Pa;
c) Where tested according to the method in 6.5.4, the peak inhalation resistance of
PAPR under power-on state shall not exceed 700Pa.
5.5.2 PAPR with loose-fitting facepiece and loose-fitting hood
Where tested according to the method in 6.5.5, the positive pressure in facepiece or hood
shall not exceed 500Pa.
5.6 Visor
5.6.1 Visual field
Where tested according to the method in 6.6, the tight-fitting facepiece shall meet the
requirements of 5.1.7, GB 2890-2009; the total visual field of loose-fitting facepiece and
loose-fitting hood shall not be less than 70%. Where there are various sizes of facepiece
or hood, each size shall meet this requirement.
This requirement is not applicable to the facepiece or hood claimed to have welding
protection function.
5.6.2 Mechanical strength of visor
Where tested according to the method in 6.7, the visor shall be free from any form of
damage, and the facepiece or hood after test shall also meet the requirements of 5.7.
5.6.3 Prevention against high-speed particle impact
If PAPR facepiece or hood is claimed to have prevention performance against high-speed
particle impact, it shall meet the technical requirements for visor in 5.11, GB 14866-2006.
The facepiece or hood after test shall also meet the requirements of 5.7.
5.6.4 Special requirements for welding protection
If PAPR facepiece or hood is claimed to have welding protection function, it shall not only
meet the applicable requirements in 5.1, 5.2 or 5.3 of this standard, but also comply with
the following requirements:
a) As for the non-automatic dimmer welding filter glass, its length shall not be less
5.8 Breathing Hose
5.8.1 As tested according to the method in 6.9, the peak inhalation resistance of PAPR
with tight-fitting facepiece shall not exceed 350Pa prior to imposing pressure; after
imposing pressure, the change value of peak inhalation resistance shall not exceed 50Pa;
as for the PAPR with loose-fitting facepiece or loose-fitting hood, the decrease of flow rate
under pressure shall not exceed 5% of the MMDF value; where checked 5min after the
elimination of pressure according to the method in 6.2, the breathing hose shall be free
from deformation.
5.8.2 Where tested according to the method in 6.19, the breathing hose shall not restrict
the free movement of the wearer's head, and shall meet the requirements of GB/T
23465-2009.
5.9 Dead Space
Where tested according to the method in 6.10, the volume fraction of average carbon
dioxide content in inhaled air of PAPR with tight-fitting facepiece under power-on state
shall not exceed 1%, while that under power-off state shall not exceed 2%; the volume
fraction of average carbon dioxide content in inhaled air of PAPR with loose-fitting
facepiece and loose-fitting hood under power-on state shall not exceed 1%.
5.10 Filter Element
5.10.1 Basic requirements
Where checked according to the method in 6.2, the design and material of filter element
shall meet the following requirements:
a) The design of gas and/or vapor filter element shall not allow for refilling of
adsorbent;
b) Replacement shall be carried out without special tools;
c) The part preventing particles of combination filter element shall be located in the
air inflow direction;
d) After the pretreatment specified in 6.3.2, it shall be free from mechanical damage
and meet the requirements of 5.10.2 and (or) 5.10.3.
5.10.2 Particle filter efficiency
According to the method in 6.11, conduct the test with oily particle. The filter efficiency of
Grade P95 particle filter element and combination filter element shall not be less than
5.14 Checking Device
5.14.1 Where checked according to the method in 6.2, each set of PAPR shall include
checking device to check whether PAPR reaches MMDF.
5.14.2 Where the checking device displays that the air supply volume of PAPR is
acceptable, the actual flow rate shall not be lower than MMDF, after the test of actual flow
rate according to 6.4, confirm whether the checking device is in accurate and reliable
display according to the application method of checking device.
5.15 Warning Device
PAPR should be equipped with warning device.
If PAPR is equipped with warning device, carry out checking according to the method in
6.2, during application process, the warning message shall not be closed and shall be
sensed by the wearer, and the method for wearer checking whether the warning device is
normal shall be provided.
Where tested according to the method in 6.19, it is confirmed that the warning device may
be checked. See Annex B for the warning function of PAPR.
5.16 Intrinsic Safety and Electrical Part
PAPR shall meet the following requirements:
a) Where tested according to the method in 6.19, it is confirmed that the design of
PAPR electrical part will not restrict the air flow properly or make the air flow
backflow;
b) If it is declared that PAPR is provided with intrinsic safety in flammable and
combustible environment, the intrinsic safety of its integral and electrical part shall
meet the requirements of GB 3836.1-2010 and GB 3836.4-2010;
c) It is declared that PAPR can be used in explosive dust site, the intrinsic safety of its
integral and electrical part shall also meet the requirements of Protection by
Intrinsic Safety “iD” in GB 12476.4-2010 or Protection by Enclosures "tD" in IEC
61241-1:2004;
d) Where checked according to the method in 6.2, the battery adopted shall be of
fluid type and not be of overflow type;
e) Where tested according to the method in 6.19, the battery adopted shall be
5.20 Information to be Provided by the Manufacturer
5.20.1 Complete set of respirator
Where checked according to the method in 6.2, each set of respirator shall be provided
with Chinese instructions to make the trained personnel master correct use method. The
contents of selection, use and maintenance of relevant product shall be consistent with
the relevant requirements of GB/T 18664-2002 and shall at least include the following
information:
a) Application scope and restriction;
b) Type of PAPR (see Table 1);
c) Information on correct wearing, use, maintenance, charging (if applicable) and
storage, recommended use temperature and storage temperature as well as
humidity range.
d) Explanation about the allowed filter elements and their combined components in
detail and that of the corresponding PAPR type.
Note: the use of illustration, component No. and label may assist explanation.
e) Detailed suggestions for use and replacement of filter element;
f) The filter element shall be disposable where used for CO protection;
g) The product shall be provided with the contact information of the manufacturer or
its designated service provider to help the user understand other information in
the specific environment, e.g. suggestions about the applicability of filter element
of certain type;
h) Corresponding instruction shall be provided where there is end-of-service-life
indicator;
i) The manufacturer's design duration under the state where the battery is used by
matching with different types of PAPR (if applicable);
j) Where the battery and air supply fan are dismountable, the manufacturer's design
duration information of battery shall be indicated on the battery body;
k) Where the battery and air supply fan are designed as a whole, the manufacturer's
design duration information of battery shall be indicated on the air supply fan;
d) Warning provided for possible wrong use.
6 Test
6.1 Samples and Ambient Conditions of Test
6.1.1 Test samples
Unless otherwise specified, all tests for complete set of PAPR need two sets of samples,
one is the received sample while the other is the pretreated sample. Where there are
different sizes of facepiece or hood, at least 1 sample of each size shall be provided.
Unless otherwise specified, the filter element tested together with PAPR is the received
sample.
Note: see Annex D to understand the sample information required by each test method.
6.1.2 Ambient conditions of test
Unless otherwise specified, the test shall be conducted under the following ambient
conditions:
a) Temperature range: 16~32℃;
b) Relative humidity range: 20~80%.
According to the requirements of Annex B, GB 2626-2006, the main dimensions of test
head models are classified into three sizes - large, medium and small.
6.2 Visual Checking
Visual checking includes checking for PAPR integrity, information provided by the
manufacturer and identification.
According to technical requirements, visual appearance checking shall be conducted for
the sample prior to the performance test in the laboratory, and the result shall be reported.
6.3 Pretreatment
6.3.1 Temperature and humidity pretreatment of a complete set of respirator
Place the complete set of respirator under the minimum temperature and minimum
humidity condition noted in the information provided by manufacturer for (72±1)h, make it
Where the initial actual flow rate is less than MMDF, stop the test.
During test, the checking device shall be verified to see whether it's able to indicate
MMDF condition correctly and report the result.
6.4.5 Manufacturer's design duration
After the initial actual flow rate is tested, the test device shall be dismantled and the tested
sample be kept in working state; at 1h before manufacturer's design duration, install the
test system again for retest and test the flow rate according to the methods in 6.4.4.
The total test time means the test period from initial actual flow rate to final actual flow rate,
which shall not be less than the manufacturer's design duration.
6.5 Respiratory Resistance
6.5.1 Test devices
Test devices include:
a) Breathing machine: with breathing rate range of 10~40 times/min and tidal
volume regulating range of 1.0~3.0L;
b) Flowmeter: with measuring range of 0~500L/min and precision of 3%;
c) Differential pressure gauge: with measuring range of at least 0~1500Pa and
precision of 1Pa;
d) Test head model: with breathing hose at opening;
e) Air pump: with pumping flow rate not less than 100L/min.
6.5.2 Inhalation resistance of PAPR with tight-fitting facepiece under power-off
state
Put the facepiece on a test head model with appropriate size, adjust the respiratory rate of
breathing machine to be 20 times/min and tidal volume be 1.5L with fully charged battery
and clean filter element under power-off state, and then test the peak static pressure (Pa)
near the mouth and nose as well as that in inhalation. Test all filter elements, which shall
meet the requirements.
6.5.3 Inhalation resistance of PAPR with tight-fitting facepiece under power-on
state
respiratory area of respirator, and then obtain the inward leakage of respirator through
calculation. During the test, the reduced reagent concentration caused by filtration of
tested sample shall not affect the precision of test and shall maintain the reagent
concentration in test environment within the specified range.
6.8.4 Test devices and conditions
Sodium chloride or oily particle shall be adopted for test, and the test devices and
conditions shall meet the requirements of 6.4.2, GB 2626-20006.
6.8.5 Test procedures
Adjust the flow rate of sampling tube on facepiece with flow rate control device to control
the flow rate within 1~2L/min.
Inform the examinees that they are allowed to adjust hood and facepiece during the test,
but such action is required to be retested; the examinees shall not know test result during
the test.
Introduce the particles for test into the testing cabin and make their concentration meet
the requirement.
The examinee properly wears the tested respirator in clean air zone, and conduct
tight-fitting checking for tight-fitting facepiece under power-off state. After passing the
checking, connect the sampling tube to test instrument, test the background concentration
in facepiece or hood outside of the testing bin when the examinee respires, determine 5
data and take the arithmetic average as the background concentration ca.
Where the examinee cannot realize tight fitting with the facepiece, the test shall be
stopped. Record the facial form of examinee, replace him/her and note such information in
report.
Order the examinee to enter into the testing bin and connect the sampling tube to the
particle tester without particle contamination and ensure its air tightness; after
concentration of test medium in the testing bin is stable, complete the following actions in
sequence.
a) Keep the head still and quiet for 2min;
b) Turn the head left and right (about 15 times/min, like checking the left and right
sides of wall in laneway) for 2min;
c) Look up/down (about 15 times/min) for 2min;
Keys:
1 -- movable disc;
2 -- breathing hose.
Figure 6 -- Schematic Diagram for Test Device of Compression
Resistance of Breathing Hose
6.9.2 Test method of PAPR with tight-fitting facepiece
Adjust PAPR till it meets MMDF condition, start fan, and test the peak inhalation
resistance according to the methods in 6.5.3; place the breathing hose in the middle of
two discs, apply 50N pressure (including the deadweight of upper disc) to the breathing
hose, and test the peak inhalation resistance again according to the methods in 6.5.3.
Where there are multiple breathing hoses, each breathing hose shall be tested and bear
50N load.
Record the peak and change value of inhalation resistance after loading.
6.9.3 Test methods of PAPR with loose-fitting facepiece or loose-fitting hood
Adjust PAPR till it meets MMDF condition, start fan and test the flow rate according to the
methods in 6.4.4, and the flow rate shall meet MMDF; place the breathing hose in the
middle of two discs, apply 50N pressure (including the deadweight of upper disc) to the
breathing hose, and test the flow rate again according to the methods in 6.4.4.
Where there are multiple breathing hoses, each breathing hose shall be tested and bear
the test with 50N force loaded.
Record the flow rate before and after loading as well as the change of flow rate
corresponding to MMDF after loading, expressed in %.
6.10 Dead Space
6.10.1 Sample quantity
One sample received, or one sample received of each size (if applicable).
6.10.2 Test device
The same as 6.9.2, GB 2626-2006.
6.10.3 Test conditions
As for the positive pressure PAPR with tight-fitting facepiece, the test flow rate is relevant
to the product and the peak interactive flow rate OP which is determined according to the
methods in 6.14 shall be used; where multiple filter elements are adopted, the flow rate
shall be divided equally; where multiple filter elements may be used separately, test shall
be carried out by taking them as single filter element.
As for the PAPR with loose-fitting facepiece and loose-fitting hood, the test flow rate shall
be the initial actual flow rate determined according to the methods in 6.4.4; where multiple
filter elements are adopted, the flow rate shall be divided equally; where multiple filter
elements may be used separately, test shall be carried out by taking them as single filter
element.
6.11.3 Test methods
Set the filter efficiency testing system to the test state and adjust relevant test parameters.
After starting the test, initial filter efficiency shall be recorded and filter efficiency of filter
element in the process of loading shall be continuously recorded. The loading weight of
filter element shall meet the requirements for 6.11.2; during the test, whenever the filter
efficiency is less than the limit of such level, the test shall be stopped; where the
accumulated particles has reached the specified loading weight yet the filter efficiency is
dropping, the test shall be continued till the filter efficiency doesn't reduce any longer or till
the filter efficiency is less than the limit of such level.
6.12 Protective Time
6.12.1 Sample quantity and requirements
Four samples, among which two samples are those subjecting to pretreatment according
to 6.3.2, and the other two samples are those subjecting to pretreatment according to
6.3.1 and 6.3.2 successively under the original packaging or sealing state. The samples,
after subjecting to pretreatment, shall be placed in the airtight container and be tested
within 10h.
6.12.2 Test devices
Test devices include:
a) Timer: with division value of 0.1s and precision of Grade 1;
b) Thermometer: 0~50℃, with precision of 0.1℃;
c) Flowmeter: 0~200L/min, with precision of Grade 1;
b) Desorption process: make the filter element adsorb test medium gas or vapor for
10min according to the test condition specified in a); seal the filter element and
store it in (20±1)℃ for (3±1) days; make the clean gas pass through the filter
element for 2h in the test flow rate specified in 6.12.3 under the conditions of
(20±1)℃ and (70±2)% relative humidity; test the concentration of test medium in
the gas passing through the filter element shall be tested in real time and it shall
not exceed the penetrating concentration specified in Table 7.
6.12.5 Test result
During each test, only the actual concentration of test medium is within the permissible
variation range specified in 6.12.3 a), the test result may be valid. As for the test of each
group of filter elements, the minimum shall be taken as the test result. As for the filter
element with end-of-service-life indicator, its performance shall be assessed during
protective time test and be reported in test result.
The protective time measured in actual test concentration shall be converted to that in
specified test concentration according to Formula (6):
1 1
t ct...
......