GB 2626-2019_English: PDF (GB2626-2019)
| Standard ID | Contents [version] | USD | STEP2 | [PDF] delivered in | Standard Title (Description) | Status | PDF |
| GB 2626-2019 | English | 265 |
Add to Cart
|
0--9 seconds. Auto-delivery
|
[N95/KN95 face mask] Respiratory protection -- Non-powered air-purifying particle respirator
| Valid |
GB 2626-2019
|
| GB 2626-2006 | English | 115 |
Add to Cart
|
0--9 seconds. Auto-delivery
|
[Replaced by GB 2626-2019] Respiratory protective equipment -- Non-powered air-purifying particle respirator
| Obsolete |
GB 2626-2006
|
| GB/T 2626-1992 | English | 359 |
Add to Cart
|
3 days [Need to translate]
|
General technical requirements for self-inhalation filtertype dust respirator
| Obsolete |
GB/T 2626-1992
|
| Standard ID | GB 2626-2019 (GB2626-2019) | | Description (Translated English) | [N95/KN95 face mask] Respiratory protection -- Non-powered air-purifying particle respirator | | Sector / Industry | National Standard | | Classification of Chinese Standard | C73 | | Classification of International Standard | 13.340.30 | | Word Count Estimation | 41,490 | | Date of Issue | 2019-12-31 | | Date of Implementation | 2020-07-01 | | Drafting Organization | Sinosteel Wuhan Institute of Safety and Environmental Protection Co., Ltd., Institute of Chemical Defense, Academy of Military Sciences, 3M China Co., Ltd. | | Administrative Organization | Ministry of Emergency Management of the People's Republic of China | | Proposing organization | Ministry of Emergency Management of the People's Republic of China | | Issuing agency(ies) | State Administration for Market Regulation, National Standardization Administration | | Summary | This standard applies to self-priming filter respirators for protection against particulate matter. This standard does not apply to respirators for protection against harmful gases and vapors, and does not apply to respirators for oxygen-deficient environments, underwater operations, escape and firefighting. | | Standard ID | GB 2626-2006 (GB2626-2006) | | Description (Translated English) | [Replaced by GB 2626-2019 from July 2020] Respiratory protective equipment. Non-powered air-purifying particle respirator | | Sector / Industry | National Standard | | Classification of Chinese Standard | C73 | | Classification of International Standard | 13.340.30 | | Word Count Estimation | 27,259 | | Date of Issue | 2006-03-27 | | Date of Implementation | 2006-12-01 | | Older Standard (superseded by this standard) | GB/T 2626-1992; GB/T 6223-1997; GB/T 6224.1-1986; GB/T 6224.2-1986; GB/T 6224.3-1986; GB/T 6224.4-1986 | | Quoted Standard | GB/T 2891; GB/T 5703; GB/T 10586; GB/T 10589; GB/T 11158 | | Drafting Organization | Wuhan Institute of Safety and Environmental Protection | | Administrative Organization | National Personal Protective Equipment Standardization Technical Committee | | Regulation (derived from) | Announcement of Newly Approved National Standards No. 5, 2006 (No. 92 overall) | | Proposing organization | State Production Safety Supervision Administration | | Issuing agency(ies) | Administration of Quality Supervision, Inspection and Quarantine of People's Republic of China; Standardization Administration of China | | Summary | This Chinese standard specifies the self-absorption filter respirators against particles technical requirements, test methods and marking. This standard applies to all types of particulate matter protective self-absorption filter respirators. | | Standard ID | GB/T 2626-1992 (GB/T2626-1992) | | Description (Translated English) | General technical requirements for self-inhalation filtertype dust respirator | | Sector / Industry | National Standard (Recommended) | | Classification of Chinese Standard | C73 | | Classification of International Standard | 13.340.30 | | Word Count Estimation | 9,916 | | Date of Issue | 1992/9/2 | | Date of Implementation | 1993/3/1 | | Older Standard (superseded by this standard) | GB 2626-1981 | | Quoted Standard | GB 2428; GB 2828; GB 2829; GB 5748; GB/T 12903 | | Regulation (derived from) | Announcement of Newly Approved National Standards No. 5, 2006 (No. 92 overall) | | Proposing organization | Ministry of Labor of the People Republic of China | | Issuing agency(ies) | State Bureau of Technical Supervision |
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......
......
GB 2626-2006
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
ICS 13.340.30
C 73
Replacing GB/T 2626-1992, GB/T 6223-1997, GB/T 6224.1~6224.4-1986
Respiratory protective equipment -
Non-powered air-purifying particle respirator
ISSUED ON: MARCH 27, 2006
IMPLEMENTED ON: DECEMBER 01, 2006
Issued by: General Administration of Quality Supervision, Inspection and
Quarantine of the PRC;
Standardization Administration of the PRC.
Table of Contents
Foreword ... 3
1 Scope ... 5
2 Normative references ... 5
3 Terms and definitions ... 6
4 Classification and marking ... 8
5 Technical requirements ... 9
6 Testing methods ... 15
7 Identification ... 33
Appendix A (Informative) Summary of testing requirements ... 35
Appendix B (Informative) Main dimensions of test head mold ... 38
Appendix C (Informative) Comparison of the revised standard with the previous
standard and some superseded standards ... 39
Bibliography ... 42
Respiratory protective equipment -
Non-powered air-purifying particle respirator
1 Scope
This Standard specifies the technical requirements, testing methods, and
identification of non-powered air-purifying particle respirator.
This Standard applies to non-powered air-purifying respiratory protective
equipment against all kinds of particles.
This Standard does not apply to respiratory protective equipment against
harmful gases and vapors. It does not apply to the respiratory protective
equipment for hypoxic environments, underwater operations, escape, fire-
fighting.
2 Normative references
The following documents contain provisions which, through reference in this
Standard, constitute provisions of this Standard. For the dated references, their
subsequent amendments (excluding corrections) or revisions do not apply to
this Standard. However, the parties who enter into agreement based on this
Standard are encouraged to investigate whether the latest editions of these
documents are applicable. For undated reference documents, the latest
editions apply to this Standard.
GB/T 2891 Performance test methods for facepiece of filter type respirator
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
3 Terms and definitions
The following terms and definitions apply to this Standard.
3.1 Particle
Solid, liquid or particle mixed with solid and liquid suspended in air, such as
dust, fume, 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 Fume
The tiny solid particles suspended in the air, which are generally produced by
the condensation of gas or vapor, and of which the particle size is usually
smaller than that of dust.
[GB/T 18664-2002, definition 3.1.17]
3.4 Mist
The tiny droplets suspended in the air.
[GB/T 18664-2002, definition 3.1.18]
3.5 Microorganism
Tiny creatures in nature with small shapes and simple structures which cannot
be observed directly with the eye and can only be seen under an optical
microscope or an electron microscope.
3.6 Non-powered air-purifying respiratory protective equipment
Filtered respiratory protective equipment that relies on the wearer’s breathing
to overcome the airflow resistance of the component.
[GB/T 18664-2002 , definition 3.1.3]
3.7 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. The tight-fitting facepiece is divided into a half facepiece and a full
facepiece.
[GB/T 18664-2002, definition 3.1.5]
3.8 Half facepiece
A tight-fitting facepiece that covers the mouth and nose, or covers the mouth,
nose, and jaw.
3.9 Full facepiece
A tight-fitting facepiece that covers mouth, nose, eyes, and jaw.
3.10 Disposable facepiece
A half facepiece mainly composed of a filter material, with or without an
exhalation valve, which cannot be cleaned and reused and shall be discarded
immediately when any component fails.
3.11 Replaceable facepiece
A tight-fitting facepiece with single or multiple replaceable filter elements, with
or without breathing valve, with or without breathing hose.
3.12 Inhalation valve
The check valve on the respiratory protective equipment, which only allows
inhalable gas to enter the facepiece and prevents exhaled air from exiting
through it.
3.13 Exhalation valve
The check valve on the respiratory protective equipment, which only allows
exhaled gas to exit the facepiece and prevents inhaled air from entering the
facepiece through it.
3.14 Breathing hose
A flexible, air-tight air hose for connecting a facepiece to a filter element.
3.15 Filter element
Filter materials or filter components used in air-purifying respiratory protective
equipment to filter out harmful substances in the inhaled air.
Example: canisters (filter cartridges), dust canisters, filter media, etc.
[GB/T 18664-2002, definition 3.1.22]
3.16 Filter efficiency
Percentage of particle removed by the filter element under specified testing
conditions.
3.17 Total inward leakage; TIL
The ratio OF the concentration of the simulant leaking into the facepiece from
all the facepiece components including the filter element TO the concentration
of the simulant in the inhaled air, when the subject inhales, under the testing
conditions specified by the laboratory, expressed as a percentage.
3.18 Inward leakage; IL
The ratio OF the concentration of the simulant leaking into the facepiece from
all the facepiece components other than the filter element TO the concentration
of the simulant in the inhaled air, when the subject inhales, under the testing
conditions specified by the laboratory, expressed as a percentage.
3.20 Head harness
A component for fixing the facepiece on the head.
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, according to the filtration performance, 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
harness of replaceable half facepiece and full facepiece shall be designed
to be replaceable;
c) There shall be as little dead space and larger field of view as possible;
e) Respiratory protective equipment which uses replaceable filter elements,
inhalation valves, exhalation valves, head harness shall be designed for
easy replacement; meanwhile it allows the user to check the airtightness
of the facepiece and face at any time and conveniently;
f) The breathing hose shall not restrict the movement of the head or the user;
it shall not affect the tightness of the facepiece; it shall not restrict or block
the airflow;
g) The structure of the disposable facepiece shall ensure close fit with the
face; meanwhile it shall not deform during service life.
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. The head harness shall be
adjustable. The head harness of replaceable facepiece shall be designed to be
replaceable. The lenses of the full facepiece, when wearing, shall not affect the
vision, such as fogging. 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 identifications and various information as provided by the
manufacturer.
5.3 Filter efficiency
USE sodium chloride (NaCl) particles to test the type N filter elements. USE
dioctyl phthalate (DOP) or oily particles (such as paraffin oil) of equivalent
nature to test the type P 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.
facepiece within 60 s shall not be greater than 100 Pa.
5.15 Information to be provided by the manufacturer
Perform inspection in accordance with the method of 6.1.
It shall, in accordance with the relevant provisions of GB/T 18664, judge the
correctness of the information provided by the manufacturer.
5.15.1 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;
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) Advice on when to replace the filter element;
7) If applicable, maintenance methods (e.g. cleaning and disinfection
methods);
8) Storage method;
9) Meaning of any symbols and icons used.
d) It shall provide warnings about problems that may be encountered during
use, such as:
1) Fitness;
2) The hair under the seal frame will cause the facepiece to leak;
3) Air quality (pollutants, hypoxia, etc.).
e) The information shall be clear; it may add the help explanations such as
commentary, part number and labeling.
5.16 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
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 method
Note: The pretreatment method used shall avoid thermal shock.
Remove the sample from the original packaging and process it in the following
order:
6.2.2 Mechanical strength pretreatment
It is only applicable to replaceable filter elements.
6.2.2.1 Number of samples and requirements
2 un-conditioned 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. Through
the rotation of the cam, the steel box is lifted by 20 mm. 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 r/min.
6.2.2.3 Testing method
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 spacing and free vertical movement distance.
6.3.2.1 Testing system for filter efficiency of NaCl particle
The main technical parameters are as follows:
a) The concentration of NaCl particles does not exceed 200 mg/m3. The
count median diameter (CMD) is (0.075±0.020) μm. The geometric
standard deviation of the particle size distribution is not greater than 1.86;
b) The dynamic range of the particle detector is (0.001~200) mg/m3; the
accuracy is 1%;
c) The testing flow range is (30~100) L/min; the accuracy is 2%;
d) The testing range of filter efficiency is 0~99.999%;
e) There shall be a device capable of neutralizing the charge of the particles
that has occurred.
6.3.2.3 Testing conditions
The testing temperature condition of KN type filter element is (25±5)°C; the
relative humidity is (30±10)%; the concentration of NaCl particles shall not
exceed 200 mg/m3.
The testing temperature condition of KP type filter element is (25±5)°C; the
concentration of oily particles shall not exceed 200 mg/m3.
The testing flow rate is (85±4) L/min. If it is a multiple filter element, the flow
rate shall be divided equally; for example, for a dual filter element design, the
testing flow rate of each filter element shall be (42.5±2) L/min. If multiple filter
elements are likely to be used alone, they shall be tested according to the
testing conditions of a single filter element.
6.3.3 Testing method
First adjust the filter efficiency testing system to the testing state; adjust the
relevant test parameters.
USE appropriate fixture to connect the disposable facepiece (if there is an
exhalation valve, the exhalation valve shall be sealed) or the filter element to
the testing device in an air-tight manner.
After the testing starts, record the initial filter efficiency. The testing shall be
continued until the filter efficiency reaches the lowest point, or until the filter
material has accumulated (200±5) mg of particle. For type KP filter material, if
the amount of accumulated particle on the filter material reaches (200±5) mg,
but the efficiency decreases at the same time, the testing shall be continued
until the efficiency stops decreasing. Filter efficiency results shall be
continuously recorded.
6.4 Leakage
6.4.1 Number of samples and requirements
10 samples of disposable facepiece, wherein 5 of them are untreated samples
and the other 5 are samples after pretreatment in 6.2.1. If the samples under
test have different numbers, there shall be at least two samples for each number.
2 samples of replaceable facepiece, wherein 1 of them is an untreated sample
and the other is a sample as pretreated in 6.2.1. If the samples under test have
different numbers, there shall be two samples for each number; wherein 1 of
them is an untreated sample and the other is the sample as pretreated in 6.2.1.
6.4.2 Testing equipment
6.4.2.2 The inspection chamber has a closable chamber with a large
observation window, the size of which allows the subject to complete the
prescribed actions. It shall be so designed that the simulant is to be uniformly
fed in from the top of the chamber and discharged from the exhaust port at the
lower part of the chamber.
6.4.2.3 The simulant generating device shall meet one of the following
requirements:
1) The generated gas volume of NaCl particles is not less than 100 L/min;
the particle concentration is (10±2) mg/m3; the concentration change in
5 - Sample from the sampling tube of testing chamber;
6 - Sampling tube for tested sample;
7 - Air pump;
8 - Replenished fresh air;
9 - Particle detector.
Figure 2 -- Schematic diagram of the testing system of TIL and IL
6.4.3 Testing conditions
6.4.3.1 Before testing, the sample shall be checked and confirmed complete in
accordance with the method of 6.1; meanwhile there is no danger to the subject.
6.4.3.2 Personnel familiar with the use of such products shall be selected for
testing. SELECT 10 beard-shaving subjects whose face shapes shall be
representative of the users of this type of product, considering the differences
in face shape and gender; but shall not include those with significantly abnormal
face shapes. According to the requirements of GB/T 5703, measure and record
the morphological face length and face width data of the subject.
6.4.3.3 The sampling flow rate of particle shall be controlled to (1~2) L/min.
6.4.3.4 The sampling position of particle in the test chamber shall be located in
the active area of the subject's head; the sampling position of particle in the
sample under test shall be located as far as possible at the centerline of the
subject's mouth; the sampling tube shall be air-tightly connected to the sample
under test.
6.4.3.5 The subjects first read the usage method of the samples under test. If
the samples under test have different numbers, the most appropriate number
shall be selected for the subject as required. The subject shall also understand
the testing requirements and methods.
6.4.3.6 When testing the inward leakage (IL) of replaceable half facepieces and
full facepieces, it shall use the filter element of at least KP100 and equivalent
resistance instead of the original filter element of the facepiece.
6.4.4 Testing method
Prepare the sample to be tested and install the sampling tube. The mounting
position of the sampling tube shall be as close to the right front side of the user's
mouth and nose as possible. For disposable facepieces, it shall take necessary
measures to prevent the sampling tube from affecting the position of the
facepiece during the testing. When applicable, connect KP100 grade filter
elements. CHECK the testing system to confirm that it is in normal working
condition.
LEAD the particle into the testing chamber to make the concentration reach the
requirements.
The subject, in the clean air area, wears the sample under test; checks the
airtightness according to the usage method; then connects the sampling tube
to the particle detector. MEASURE the background concentration in the
facepiece when the subject is breathing outside the testing chamber. MAKE 5
measurements. TAKE the arithmetic mean as the background concentration.
Have the subject enter the testing chamber and connect the sampling tube to
the particle detector while avoiding particle contamination. Then the subject,
according to time requirements, completes the following actions in order:
1) Head still and not talking for 2 min;
2) TURN the head to the left and right (about 15 times) to see the left and
right walls of the testing chamber for 2 min;
5) Head still and not talking for 2 min.
During each action, it shall test the particle concentration in the testing chamber
and the facepiece at the same time. Generally, it only tests the last 100 s time
interval of this action; avoids testing the cross section of the actions. For each
action, it shall test 5 data. Calculate the arithmetic mean as the result of the
action.
During the testing, subjects are allowed to adjust the facepiece they are wearing;
but the testing of the action must be redone.
When using NaCl particle for testing, the total inward leakage and inward
leakage are calculated according to formula (1):
Where:
C - The particle concentration in the facepiece under test during each action;
Ca - The background concentration of particle in the facepiece under test;
C0 - The particle concentration in the testing chamber during each action.
When using oily particle for testing, the total inward leakage and inward leakage
are calculated according to formula (2):
6.5 Inhalation resistance
6.5.1 Number of samples and requirements
4 samples, wherein 2 of them are untreated samples and the other 2 are
samples as pretreated in 6.2.1. If the samples under test have different numbers,
there shall be two samples for each number; wherein 1 of them is an untreated
sample and the other is the sample as pretreated in 6.2.1.
6.5.2 Testing equipment
6.5.2.4 Test head mold: Breathing hose is installed at the mouth of the test head
mold. The main dimensions shall refer to the requirements of Appendix B. It is
divided into 3 size types: large, medium, small.
6.5.2.5 The suction volume of the suction pump is not less than 100 L/min.
6.5.3 Testing conditions
6.5.3.1 If applicable, the sample under test shall include replaceable filter
elements.
6.5.3.2 The ventilation volume is constant at (85±1) L/min.
6.5.4 Testing method
CHECK the air tightness and working status of the testing device. Adjust the
ventilation volume to (85±1) L/min. SET the system resistance of the testing
device to 0.
there shall be two samples for each number; wherein 1 of them is an untreated
sample and the other is the sample as pretreated in 6.2.1.
6.6.2 Testing equipment
6.6.2.1 The schematic diagram of the testing device for exhalation resistance
is as shown in Figure 3.
6.6.2.2 The flow meter is the same as 6.5.2.2.
6.6.2.3 The micromanometer is the same as 6.5.2.3.
6.6.2.4 The test head mold is the same as 6.5.2.4.
6.6.2.5 The displacement of the air compressor is not less than 100 L/min.
6.6.3 Testing conditions
Same as 6.5.3.
6.6.4 Testing method
CHECK the air tightness and working status of the testing device. Adjust the
ventilation volume to (85±1) L/min. SET the system resistance of the testing
device to 0.
PUT the sample under test on a matching test head mold; adjust the wearing
position of the facepiece and the tightness of the head harness, to ensure that
the facepiece and the test head mold are in close contact. Then adjust the
ventilation volume to (85±1) L/min; MEASURE and record the exhalation
resistance.
6.7 Air tightness of exhalation valve
6.7.1 Number of samples and requirements
4 samples, wherein 2 of them are untreated samples and the other 2 are
samples as pretreated in 6.2.1.
6.7.2 Testing equipment
6.7.3 The schematic diagram of the testing device for the exhalation valve’s air
tightness is as shown in Figure 4.
6.7.3.1 The volume of the constant volume cavity is 150±10 mL.
6.7.3.2 The micromanometer has a measurement range of 0~2000 Pa and an
accuracy of 1 Pa.
6.7.5 Testing method
After using the airtight inspection cover to seal the constant volume cavity, the
system is evacuated to a negative pressure of 1180 Pa. Within 2 min after
turning off the control valve, a pressure change shall not be observed.
Install the sample under test on a constant volume cavity and ensure tightness;
at a pumping rate of not more than 500 mL/min, make the system reach a
negative pressure of 1250 Pa; TURN off the control valve.
Timing starts when the negative pressure of the system drops to 1180 Pa.
RECORD whether the time required for the system to return to normal pressure
is less than 20 s.
6.8 Exhalation valve cover
6.8.2.2 The fixture has a proper structure and clamping degree.
6.8.2.3 The accuracy of the timer is 0.1 s.
6.8.3 Testing method
USE appropriate fixture to respectively fix the exhalation valve cover and the
facepiece of the sample under test (the fixing point shall be reasonably close to
the corresponding connection site). START the material testing machine, to
apply the axial tensile force as specified in Table 4. RECORD whether there are
fractures, slippage, deformation.
6.9 Dead space
6.9.1 Number of samples and requirements
For disposable facepiece, 3 untreated samples. For half facepiece or full
facepiece, 1 untreated sample, or 1 untreated sample per number (if applicable).
6.9.2 Testing equipment
The schematic diagram of the testing device for the dead space (CO2 content
of inhaled air) is as shown in Figure 5. Except for the breathing simulator, the
(5.0±0.1)%.
6.9.2.4 CO2 flow meter: The range is not less than 40 L/min; the accuracy is
level 2.
6.9.2.5 CO2 analysis instrument: The range is not less than 12%; the accuracy
is not less than 0.1%.
6.9.2.6 Anemometer, electric fan, etc.
6.9.3 Testing conditions
6.9.3.3 Adopt proper ventilation measures so that the concentration of CO2 in
the testing environment is not higher than 0.1%. The testing point of the CO2
concentration in the environment shall be located approximately 1 m directly in
front of the sample under test.
6.9.3.4 If disposable facepiece samples are tested, an electric fan shall be used
to blow air on the side of the sample under test, so that the velocity of the air
flow in front of the facepiece is 0.5 m/s.
6.9.4 Testing method
CHECK the testing system to confirm that it is in normal working condition.
TAKE necessary measures, to air-tightly wear the sample under test on a
matching test head mold and prevent deformation of the facepiece.
TURN on the testing device for dead space, to continuously monitor and record
the concentration of CO2 in the inhaled air and the testing environment, until it
reaches a stable value.
The 3 samples of disposable facepiece shall be tested once for each. The half
facepiece or full facepiece shall be tested repeatedly 3 times for each.
Only when the CO2 concentration in the testing environment is not greater than
0.1%, the test is valid; meanwhile the CO2 concentration in the testing
environment shall be deducted. For the testing result of the CO2 concentration
in the inhaled air, take the arithmetic mean of 3 measurements.
6.10 Field of view
Perform testing according to the method specified in GB/T 2891.
6.11 Head harness
6.11.1 Number of samples and requirements
2 samples, wherein 1 of them is an untreated sample and the other is a sample
as pretreated in 6.2.1.
6.11.2 Testing equipment
The testing equipment is the same as 6.8.2.
6.11.3 Testing method
USE the fixture to fix the head harness (non-free end) of the sample under test
and the facepiece, respectively (it shall be reasonably close to the
corresponding head harness buckle’s connection part). START the material
testing machine, to apply the tensile force as specified in Table 6. RECORD
whether there are fractures and slippage.
It shall test the connection of each head harness of the sample under test and
record the results.
6.12 Connections and connecting parts
6.12.3 Testing method
USE appropriate fixture to respectively fix the connecting parts of the sample
under test and the facepiece (the fixing point shall be reasonably close to the
corresponding connection site). START the material testing machine, to apply
the axial tensile force as specified in Table 7. RECORD whether there are
fractures, slippage, deformation.
It shall test each......
......
|