GB 2626-2006_English: PDF (GB2626-2006)
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[N95/KN95 face mask] Respiratory protection -- Non-powered air-purifying particle respirator
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GB 2626-2019
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| GB 2626-2006 | English | 115 |
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[Replaced by GB 2626-2019] Respiratory protective equipment -- Non-powered air-purifying particle respirator
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GB 2626-2006
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| GB/T 2626-1992 | English | 359 |
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General technical requirements for self-inhalation filtertype dust respirator
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GB/T 2626-1992
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Preview PDF: GB 2626-2019 Standards related to: GB 2626-2006
| 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Count Estimation | 27,259 | | Date of Issue | 2006-03-27 | | Date of Implementation | 2006-12-01 | | Older Standard (superseded by this standard) | GB/T 2626-1992; GB/T 6223-1997; GB/T 6224.1-1986; GB/T 6224.2-1986; GB/T 6224.3-1986; GB/T 6224.4-1986 | | Quoted Standard | GB/T 2891;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. |
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......
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