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GB 2626-2019: PDF in English
GB 2626-2019
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
ICS 13.340.30
C 73
Replacing GB 2626-2006
Respiratory protection - Non-powered air-purifying
particle respirator
ISSUED ON: DECEMBER 31, 2019
IMPLEMENTED ON: JULY 01, 2020
Issued by: State Administration for Market Regulation;
Standardization Administration of PRC.
Table of Contents
Foreword ... 4 
1 Scope ... 6 
2 Normative references ... 6 
3 Terms and definitions ... 7 
4 Classification and marking ... 11 
4.1 Classification of facepiece ... 11 
4.2 Classification of filter element ... 11 
4.3 Grades of filter element ... 12 
4.4 Marking ... 12 
5 Technical requirements ... 12 
5.1 Basic requirements ... 12 
5.2 Visual inspection ... 13 
5.3 Filter efficiency ... 14 
5.4 Leakage ... 14 
5.5 Breathing resistance ... 15 
5.6 Exhalation valve ... 15 
5.7 Dead space ... 16 
5.8 View field ... 16 
5.9 Head harness ... 16 
5.10 Connections and connecting parts ... 17 
5.11 Lens ... 17 
5.12 Air tightness ... 17 
5.13 Flammability ... 17 
5.14 Cleaning and disinfection ... 18 
5.15 Practical performance ... 18 
5.16 Information to be provided by the manufacturer ... 18 
5.17 Packaging ... 20 
6 Testing methods ... 20 
6.1 Visual inspection ... 20 
6.2 Pretreatment ... 20 
6.3 Filter efficiency ... 22 
6.4 Leakage ... 26 
6.5 Inhalation resistance ... 31 
6.6 Exhalation resistance ... 34 
6.7 Air tightness of exhalation valve ... 34 
6.8 Protection device of exhalation valve ... 36 
6.9 Dead space ... 36 
6.10 View field ... 38 
6.11 Head harness ... 38 
6.12 Connections and connecting parts ... 39 
6.13 Lens ... 40 
6.14 Air tightness ... 40 
6.15 Flammability ... 41 
6.16 Practical performance ... 42 
7 Product marking ... 43 
7.1 Markings on the product ... 43 
7.2 Marking on the packaging ... 43 
Appendix A (Informative) Summary of testing requirements ... 45 
Appendix B (Informative) CMD and MMAD conversion method ... 48 
Appendix C (Normative) Method for judging whether KP filter element’s loading
filter efficiency continues to decrease ... 51 
Appendix D (Normative) Main dimensions of test head mold ... 53 
Appendix E (Informative) Main differences between this standard and the 2006
edition ... 54 
References ... 57 
Foreword
This standard was drafted in accordance with the rules given in GB/T 1.1-2009.
This standard replaces GB 2626-2006 "Respiratory protection equipment -
Non-powered air-purifying particle respirator".
Compared with GB 2626-2006, the main changes in this standard are as follows:
- CHANGE the standard name from "Respiratory protection equipment -
Non-powered air-purifying particle respirator" to "Respiratory protection -
Non-powered air-purifying particle respirator";
- DELETE three terms "smoke", "fog" and "microorganism"; ADD seven
terms "penetration", "user face-seal check", "assigned protection factor",
"count median diameter", "mass median diameter", "aerodynamic
diameter", "mass median aerodynamic diameter" (see 3.14 and 3.19 ~
3.24);
- MODIFY the requirements for inspiratory resistance and expiratory
resistance of various types of respirators (see 5.5);
- MODIFY the requirements and test methods for air tightness of exhalation
valves (see 5.6.1 and 6.7);
- MODIFY the name of the exhalation valve cover to an exhalation valve
protection device (see 5.6.2 and 6.8);
- MODIFY the vision requirements for various types of respirators (see 5.8);
- ADD the requirements and test methods for products that the manufacturer
claims filter elements can be reused after cleaning and / or disinfection [see
5.14.1, 5.16d), 6.2.3];
- ADD the practical performance requirements and testing methods (see 5.15
and 6.16);
- ADD a description of the method of judging the service life of filter elements
in the information part to be provided by the manufacturer; ADD the
application restrictions on non-flame-retardant products (see 5.16);
- In the testing method of filter efficiency, ADD the conversion method of
particle size used for testing of filter efficiency (see Appendix B),
requirements for accuracy and resolution of particle detector for the filter
efficiency testing equipment (see 6.3.2) and judgment of loading end point
(see 6.3.4.4, 6.3.4.5, 6.3.4.6, Appendix C); ADD the requirements for load
(see 6.3.3);
- In the testing method of leakage, ADD requirements for sample inspection
(see 6.4.1.4); ADD the accuracy requirements for particle detectors (see
6.4.2.4); ADD a formula for calculating the inward leakage by subject [see
formula (5)];
- ADD the schematic diagram of the structure of the built-in breathing hose
for the test head mold for breathing resistance testing and dead space
testing (see Figure 4);
- In the test method of breathing resistance, MODIFY the requirements for
the micromanometer parameters (see 6.5.2.3); ADD the requirements for
airtightness between the respirator facepiece and the test head mold (see
6.5.4 and 6.6.4);
- MODIFY the schematic diagram of the testing device for dead space (see
Figure 6);
- In the test method of head harness, ADD the requirement to apply the test
tensile force in the direction in which the head harness is stretched during
normal use (see 6.11.3).
Note: See Appendix E for the main differences between this standard and the
2006 edition.
This standard was proposed by and shall be under the jurisdiction of the
Ministry of Emergency Management of the People's Republic of China.
Drafting organizations of this standard: China Iron and Steel Group Wuhan
Safety and Environmental Protection Research Institute Co., Ltd., Academy of
Military Science and Chemical Research Institute, 3M China Co., Ltd.
The main drafters of this standard: Cheng Jun, Ding Songtao, Yang Xiaobing,
Yao Hong, Zhou Xiaoping, Cai Xialin, Zhang Shouxin, Yu Jingjing.
This standard was first issued in 1981, revised to GB/T 2626-1992 in 1992, then
revised to GB 2626-2006 in 2006.
Respiratory protection - Non-powered air-purifying
particle respirator
1 Scope
This standard specifies the classification and marking, technical requirements,
testing methods, identification of non-powered air-purifying particle respirator.
This standard applies to non-powered air-purifying respirator that protects
against particle.
This standard does not apply to respirators that protect against harmful gases
and vapors. It does not apply to the respirators for hypoxic environments,
underwater operations, escape, fire-fighting.
2 Normative references
The following documents are essential to the application of this document. For
the dated documents, only the versions with the dates indicated are applicable
to this document; for the undated documents, only the latest version (including
all the amendments) are applicable to this standard.
GB 2890-2009 Respiratory protection - Non-powered air-purifying
respirators
GB/T 5703 Basic human body measurements for technological design
GB/T 10586 Specifications for damp heat chambers
GB/T 10589 Specifications for low temperature test chambers
GB/T 11158 Specifications for high temperature test chambers
GB/T 18664-2002 Selection, use and maintenance of respiratory protective
equipment
GB/T 23465-2009 Respiratory protective equipment - Practical performance
evaluation methods
3 Terms and definitions
The following terms and definitions apply to this document.
3.1
Particle
Solid, liquid or particle mixed with solid and liquid suspended in air, such as
dust, smoke, mist and microorganisms.
[GB/T 18664-2002, definition 3.1.15]
3.2
Dust
The tiny solid particles suspended in the air, which are generally produced
by the solid materials being broken by mechanical forces.
[GB/T 18664-2002, definition 3.1.16]
3.3
Non-powered air-purifying respirator
Filtered respirator that relies on the wearer’s breathing to overcome the
airflow resistance of the component.
[GB/T 18664-2002, definition 3.1.3]
3.4
Tight-fitting facepiece
A facepiece that can cover the mouth and nose and fit tightly to the face, or
a facepiece that can cover the eyes, mouth, and nose and fit tightly to the
head and face.
Note 1: The close-fitting facepiece is divided into a half facepiece and a full
facepiece.
Note 2: Rewrite GB/T 18664-2002, definition 3.1.5.
3.5
Half facepiece
A tight-fitting facepiece that covers the mouth and nose, or covers the mouth,
nose, and jaw.
Note: Half facepieces are divided into disposable facepieces and
replaceable half facepieces.
3.6
Full facepiece
Tight-fitting facepiece that covers eyes, mouth, nose and jaw.
3.7
Disposable facepiece
A half facepiece mainly composed of a filter material, which can be provided
with an exhalation valve.
3.8
Replaceable facepiece
Closed half-facepieces and full facepieces with single or multiple
replaceable filter elements, which can be provided with breathing valves and
/ or breathing hose.
3.9
Inhalation valve
A one-way valve that only allows inhaled air to enter the facepiece and
prevents exhaled air from exiting the facepiece through it.
[GB 2890-2009, definition 3.6]
3.10
Exhalation valve
A one-way valve that only allows exhaled air to exit the facepiece and
prevents inhaled air from entering the facepiece through it.
[GB 2890-2009, definition 3.7]
3.11
Breathing hose
A flexible, air-tight air hose for connecting a facepiece to a filter element.
3.12
Filter element
Filter materials or filter components used in filtered respirators to filter out
harmful substances in the inhaled air.
Examples: canisters (filter cartridges), dust canisters, filter media, etc.
[GB/T 18664-2002, definition 3.1.22]
3.13
Filter efficiency
Under the specified testing conditions, the level of particle is filtered out by
the filter element.
3.14
Penetration
The level of particle penetrating the filter element under specified testing
conditions.
Note: Penetration = 100% - filter efficiency.
3.15
Total inward leakage; TIL
Under the specified laboratory test environment, the ratio of the
concentration of the simulant leaked into the facepiece from all the facepiece
components including the filter element when the subject inhaled to the
concentration of the simulant in the test environment outside the respirator
facepiece.
Total inward leakage = Ci / C0 × 100% ………………………… (1)
Where:
Ci - The concentration of the simulant in the respirator facepiece;
C0 - Concentration of the simulant in the test environment outside the
respirator facepiece.
3.16
Inward leakage; IL
Under the specified laboratory testing environment, the ratio of the
concentration of the simulant leaked into the facepiece from all other parts
of the facepiece except the filter element when the subject inhaled to the
concentration of the simulant in the test environment outside the respirator
facepiece.
Inward leakage = Ci/C0 × 100% ………………………… (2)
Where:
Ci - The concentration of the simulant in the respirator facepiece;
C0 - Concentration of the simulant in the test environment outside the
respirator facepiece.
3.17
Dead space
Volume fraction of carbon dioxide gas as re-inhaled from a previous
exhalation.
3.18
Head harness
A part for fixing the facepiece on the head.
3.19
User face-seal check
A simple tightness check method performed by the respirator wearer, to
ensure that the tight-fitting facepiece is worn correctly.
Note: Rewrite GB/T 18664-2002, definition 3.1.24.
3.20
Assigned protection factor
One type or category of respiratory protective equipment with suitable
functions, which is expected to reduce the concentration of air pollutants on
the premise that it is suitable for users to wear and use correctly.
Note: Rewrite GB/T 18664-2002, definition 3.1.29.
3.21
Count median diameter; CMD
When the particles are sorted according to the particle size, the particle size
at which the number of particles larger than the particle size and smaller than
the particle size each accounts for 50% of the total particle size.
3.22
Mass median diameter; MMD
When the particles are sorted according to the particle size, the particle size
at which the mass of particles larger than the particle size and smaller than
the particle size each accounts for 50% of the total particle mass.
3.23
Aerodynamic diameter
The diameter of a unit density spherical particle that has the same settling
velocity as the particle in question.
3.24
Mass median aerodynamic diameter, MMAD
When the particle is sorted according to the size of the aerodynamic particle
size, the particle size at which the mass of particles larger than the particle
size and smaller than the particle size each accounts for 50% of the total
particle mass.
4 Classification and marking
4.1 Classification of facepiece
According to the structure, the facepiece is divided into three types: disposable
facepiece, replaceable half facepiece, full facepiece.
4.2 Classification of filter element
Filter elements are divided into two categories: KN and KP. Category KN is only
suitable for filtering non-oily particles; category KP is suitable for filtering oily
and non-oily particles.
4.3 Grades of filter element
According to the level of filter efficiency, the grades of filter elements is classified
according to Table 1.
Table 1 -- Grades of filter element
Type of filter element Type of facepiece Disposable facepiece Replaceable half facepiece Full facepiece
Category KN
KN90
KN95
KN100
KN90
KN95
KN100
KN95
KN100
Category KP
KP90
KP95
KP100
KP90
KP95
KP100
KP95
KP100
4.4 Marking
The filter elements of disposable facepieces and replaceable facepieces shall
be marked with grades; the grades shall be marked with a combination of the
number of this standard and the type and grade of filter elements.
Example 1: The KN90 filter element is marked as GB 2626-2019 KN90.
Example 2: The KP100 filter element is marked as GB 2626-2019 KP100.
5 Technical requirements
5.1 Basic requirements
Check in accordance with 6.1 and evaluate in 6.16. The material and structural
design of the respirator shall meet the following requirements:
a) The material shall meet the following requirements:
1) Materials that are in direct contact with the face shall be harmless to
the skin;
2) The filter material shall be harmless to the human body;
3) The material used shall have sufficient strength; in normal use, it shall
not be damaged and deformed that affects the use effect;
4) No obvious tenderness or tingling sensation when wearing it.
b) The structural design shall meet the following requirements:
1) It shall not be easy to cause structural damage; the design, composition,
installation of components shall not pose any danger to the user;
2) The design of the head harness shall be elastic material or adjustable,
for easy wearing and removal. It shall be able to firmly fit the facepiece
on the face; there shall be no obvious compression or tenderness when
wearing. The head harness of replaceable half facepiece and full
facepiece shall be designed to be replaceable;
3) If the facepieces of the same size and the same style have different
wearing methods, they shall be tested as different products;
Note 1: Different wearing methods of the same style facepiece will affect the
tightness of the facepiece.
4) It shall not significantly affect the visual field;
5) When wearing, the lenses of the full facepiece shall not affect the vision,
such as fogging;
6) Respirators which use replaceable filter elements, inhalation valves,
exhalation valves, head harness shall be designed for easy
replacement; meanwhile it allows the wearer to check the airtightness
of the facepiece and face at any time and conveniently, to make user
face-seal check;
Note 2: See Appendix G of GB/T 18664-2002 for user face-seal check method.
7) The breathing hose shall not restrict the movement of the head or the
wearer; it shall not affect the tightness of the facepiece; it shall not
restrict or block the airflow;
8) The front side of the exhalation valve shall be protected. The exhalation
valve protection device can be a dedicated component, or it can be
protected by other components on the facepiece;
9) The structure of the disposable facepiece shall ensure close fit with the
face; meanwhile it shall not deform during normal use;
10) The parts of the replaceable facepiece (except the filter element) shall
be washable.
5.2 Visual inspection
Check it in accordance with 6.1.
The surface of the sample shall neither be damaged, deformed, nor have other
obvious defects. The material and structure of the component shall be able to
withstand normal use conditions and the temperature, humidity and mechanical
shock that may be encountered. After the temperature and humidity
pretreatment and mechanical strength pretreatment according to the method of
6.2, the components shall not fall off, be damaged or deformed. The inspection
shall also include markings and various information as provided by the
manufacturer.
5.3 Filter efficiency
Use sodium chloride (NaCl) particles to test the KN filter elements. Use dioctyl
phthalate (DOP) or oil particles (such as paraffin oil) of equivalent nature to test
the KP filter elements.
Perform testing in accordance with the method of 6.3.
In the testing process, the filter efficiency of each sample shall always meet the
requirements of Table 2.
Table 2 -- Filter efficiency
5.4 Leakage
5.4.1 TIL for disposable facepieces
Perform test in accordance with the method of 6.4. The TIL of disposable
facepieces shall meet the requirements of Table 3.
Table 3 -- TIL of disposable facepieces
Grade of filter
material
When using the TIL of each action (i.e. 10 people
x 5 actions) as the basis for evaluation, the TIL of
at least 46 of the 50 actions
When using the overall TIL as the basis for
evaluation, the overall TIL of at least 8
persons of the 10 persons under test
KN90 or KP90 < 13% < 10%
KN95 or KP95 < 11% < 8%
KN100 or KP100 < 5% < 2%
Not
applicable
Not
applicable
Category and grade of filter element Tested by sodium chloride particle Tested by oily particle
5.4.2 IL of replaceable half facepiece
Perform test in accordance with the method of 6.4. When using the IL of each
action (i.e. 10 people x 5 actions) as the basis for evaluation, the IL of at least
46 of the 50 shall be less than 5%. When using the overall IL of person as the
basis for evaluation, the overall IL of at least 8 persons of the 10 persons under
test shall be less than 2%.
5.4.3 IL of full facepiece
Perform test in accordance with the method of 6.4. When the IL of each action
is used as the basis for evaluation (i.e. 10 persons x 5 actions), the IL of each
action shall be less than 0.05%.
5.5 Breathing resistance
Perform test in accordance with the method of 6.5 and 6.6.
The inhalation resistance and exhalation resistance of all types of respirators
shall meet the requirements of Table 4.
Table 4 -- Requirements for breathing resistance
Type of facepiece
Inhalation resistance / Pa Exhalation
resistance / Pa KN90 and KP90 KN95 and KP95 KN100 and KP100
Disposable facepiece, without
exhalation valve ≤ 170 ≤ 210 ≤ 250
Same as inhalation
resistance
Disposable facepiece, with exhalation
valve ≤ 210 ≤ 250 ≤ 300
≤ 150
Replaceable half facepiece and full
facepiece including filter element ≤ 250 ≤ 300 ≤ 350
5.6 Exhalation valve
5.6.1 Air tightness of exhalation valve
Detects only half facepieces. The exhalation valve shall meet the following
requirements:
When tested according to the method of 6.7, the leakage flow rate of the
exhalation valve of each respirator shall not be greater than 30 mL/min; if the
facepiece is provided with multiple exhalation valves, the leakage airflow that
each exhalation valve shall meet shall be shared equally, for example, if the
respirator facepiece is provided with 2 exhalation valves, the leakage air flow of
each exhalation valve shall not be greater than 15 mL/min.
5.6.2 Protection device of exhalation valve
Perform test in accordance with the method of 6.8.
The exhalation valve’s protection device shall not slip, break and deform when
it is subjected to the axial tensile force as specified in Table 5.
Table 5 -- Axial tensile force that the exhalation valve’s protection device
shall withstand
Type of facepiece Disposable facepiece Replaceable facepiece
Tensile force 10 N for 10 s 50 N for 10 s
5.7 Dead space
Perform test in accordance with the method of 6.9.
The average dead space result of the respirator shall not be greater than 1%.
5.8 View field
Perform test in accordance with the method of 6.10.
The view field of the respirator shall meet the requirements of Table 6.
Table 6 -- View field
View field
Type of facepiece
Half facepiece Full facepiece Big view window Double view window
Below view field ≥ 35° ≥ 35° ≥ 35°
Overall view field Not applicable ≥ 70% ≥ 65%
Double-eye view field ≥ 65% ≥ 55% ≥ 24%
5.9 Head harness
Perform test in accordance with the method of 6.11.
Each head harness, buckle and other adjustment parts of the respirator shall
not slip or break when it is subjected to the tensile force as specified in Table 7.
Table 7 -- Tensile force that the head harness shall withstand
Type of facepiece Disposable facepiece Replaceable half facepiece Full facepiece
Tensile force 10 N for 10 s 50 N for 10 s 150 N for 10 s
5.10 Connections and connecting parts
Perform test in accordance with the method of 6.12.
Under the specified test conditions, all connections and connection parts
between the replaceable filter element and the facepiece, and between the
breathing hose and the filter element and the facepiece, shall not slip, break or
deform when subjected to the axial tensile force as specified in Table 8.
Table 8 -- Axial tensile forces that the connection and connecting parts
shall withstand
Type of facepiece Replaceable half facepiece Full facepiece
Tensile force 50 N for 10 s 250 N for 10 s
5.11 Lens
5.11.1 Only full facepieces are tested.
5.11.2 Perform test in accordance with the method of 6.13. The lens of each
sample shall not be broken or cracked. Then test the airtightness in accordance
with the method of 6.14, which shall meet the requirements of 5.12.
5.11.3 Perform test in accordance with the method of 6.16. The lens shall not
cause distortion of the visual object.
5.11.4 If a product is added with ant-dimming paste, or an anti-fogging agent is
designed to be used, the anti-fogging agent shall not use known harmful
substances; after using the ant-dimming paste and / or anti-fogging agent, it
shall not cause vision deformation or blurring; anti-fog agents shall not cause
irritation and other discomfort to humans. They are tested in accordance with
methods 6.1 and 6.16.
5.12 Air tightness
Perform test in accordance with the method of 6.14.
Under the specified testing conditions, the pressure change in each full
facepiece within 60 s shall not be greater than 100 Pa.
5.13 Flammability
5.13.1 If the product design is non-flammable, it shall provide the information in
accordance with the requirements of 5.16c) 1).
5.13.2 If the product is designed to be flame-retardant, it shall be tested in
accordance with the method of 6.15. After the parts exposed to the flame are
removed from the flame, the continuous burning time shall not exceed 5 s.
5.14 Cleaning and disinfection
5.14.1 If the product design allows the filter element to be reused after cleaning
and / or disinfection, it shall meet the requirements of 5.16d); meanwhile the
filter element shall be able to withstand the cleaning or disinfection treatment
as recommended by the manufacturer. The cleaned or disinfected sample shall
meet the requirements of 5.3 for filter efficiency, 5.4 for leakage, 5.5 for
inhalation resistance. The manufacturer shall provide the user with the correct
and effective method for determining whether the filter element will continue to
be effective after cleaning or disinfection.
5.14.2 For replaceable facepieces, the facepieces shall be able to withstand
the cleaning or disinfection treatment as recommended by the manufacturer;
the samples after cleaning or disinfection shall meet the requirements of 5.4.
5.15 Practical performance
Perform test in accordance with the method of 6.16. Under the conditions of
simulated use, the performance which is hard to be evaluated by the use of
other testing methods, such as the performance specified in 5.1b) and 5.11, the
subject will provide subjective evaluation.
If the respirator fails the test, the laboratory shall describe the test method in
detail, so that other laboratories can repeat the test process.
5.16 Information to be provided by the manufacturer
Perform inspection in accordance with the method of 6.1.
The correctness of the information provided by the manufacturer shall be
judged in accordance with the relevant provisions of GB/T 18664-2002.
The information provided by the manufacturer shall meet the following
requirements:
a) It shall be provided with the smallest sales package.
b) There shall be instructions in Chinese.
c) It shall include the following information that the user must know:
1) Application scope and restrictions, which shall include (but not limited
to) the applicable particle category (such as whether it contains oil), the
assigned protection factor of the respirator, and / or other unsuitable
application environments; if the product design is not flame-retardant,
there shall be text description that "this product is not suitable for
working places with open flames (such as welding, casting, etc.)";
2) For replaceable filter elements, explain how to use them with full
facepieces or half facepieces. If multiple filter materials are used, they
shall be indicated;
3) Assembly method of replaceable facepiece;
4) Inspection method before use;
5) How to wear and how to do air tightness check;
6) How to judge the service life of disposable facepieces;
7) For replaceable facepieces, provide advice on when to replace the
facepiece or filter element;
8) If applicable, maintenance methods (e.g. cleaning and disinfection
methods);
9) Storage method;
10) Meaning of any symbols and icons used.
d) If the product claims that the filter elements can be reused after cleaning
and / or disinfection, it shall provide the following information:
1) The specific characteristics and / or scope of the applicable particle;
2) The maximum number of times it can be cleaned and / or disinfected;
3) Method to determine whether the filter element will continue to be
effective and when to replace it after cleaning and disinfection.
e) Provide warnings about problems that may be encountered during use,
such as:
1) Fitness to the face of the wearer;
2) The hair under the seal frame will cause the facepiece to leak;
3) Air quality (pollutants, hypoxia, etc.).
f) The information shall be clear; it may add the help explanations such as
commentary, part number and labeling.
5.17 Packaging
Perform inspection in accordance with the method of 6.1.
Sales packaging shall protect the product from mechanical damage and
contamination before use.
6 Testing methods
6.1 Visual inspection
According to the requirements of various technical requirements (see Appendix
A), before performing laboratory performance testing, the samples shall be
visually inspected.
6.2 Pretreatment
6.2.1 Temperature and humidity pretreatment
6.2.1.1 Number of samples and requirements
2 un-conditioned samples; or quantities required by other testing methods.
6.2.1.2 Testing equipment
The testing equipment shall meet the following requirements:
a) The technical performance of the high temperature test chamber shall
meet the requirements of GB/T 11158;
b) The technical performance of the low temperature test chamber shall meet
the requirements of GB/T 10589;
c) The technical performance of the damp heat test chamber shall meet the
requirements of GB/T 10586.
6.2.1.3 Testing methods
Remove the samples from the original packaging and process them in the
following order:
a) Place it at (38 ± 2.5) °C and (85 ± 5)% relative humidity for (24 ± 1) h;
b) Place it in a dry environment at (70 ± 3) °C for (24 ± 1) h;
c) Store it at (-30 ± 3) °C for (24 ± 1) h.
The pretreatment method used shall avoid thermal shock; allow the sample
temperature to return to room temperature for at least 4 hours before
subsequent pretreatment or testing.
6.2.2 Mechanical strength pretreatment
6.2.2.1 Number of samples and requirements
It is only applicable to replaceable filter elements. 2 untreated samples; or
quantities required by other testing methods.
6.2.2.2 Testing equipment
The vibration test device is as shown in Figure 1. The device consists of a steel
box, a steel platform, a cam, a drive, a control system on which the sample is
placed; the steel box is fixed on a support that can be moved vertically. The
steel box is lifted by 20 mm through the rotation of the cam. Then let it fall on a
steel platform by its own weight, to generate a vibration. The mass of the steel
box shall be greater than 10 kg. The mass of the steel platform shall be at least
10 times the mass of the steel box. The cam’s rotation frequency is (100 ± 5)
r/min.
6.2.2.3 Test methods
Take the sample out of the package. The non-encapsulated filter element shall
be the smallest sales package.
Place the sample laterally in the steel box; the placement method shall ensure
that the samples will not contact each other during the test. It allows for 6 mm
horizontal movement interval and free vertical movement distance.
The duration of vibration testing is 20 min.
After the test is over, perform the follow-up tests.
In millimeters
Explanation:
...
......
(Above excerpt was released on 2020-03-21, modified on 2021-06-07, translated/reviewed by: Wayne Zheng et al.)
Source: https://www.chinesestandard.net/PDF.aspx/GB2626-2019