- 1 - ICS 13.340.30  
 
 
  
 
National Standard  
of the People's Republic of China 
  
GB xxxx-200x 
 
 
Self-contained close-circuit breathing 
apparatus of compressed oxygen 
 
 
 
   
(Draft for approval) 
 
  
 
 
Issue Date: xx-xx-200x Implem entation Date: xx-xx-200x 
 
 
 
Issued by the General Administration of Quality Supervision, Inspection and 
Quarantine of the People 's Republic of China  
 
 
 
 
- 2 - Table of Contents 
Foreword.......................................................................................................3 1 Scope..................................................................................................4 2 Normative references.......................................................................4 3 Terms and definitions......................................................................4 4 Classification and marks.................................................................5 5 Technical requirements...................................................................6 6 Test methods.....................................................................................15 7 Labelling, packaging, transportation and storage.........................26- 3 -  
Foreword 
 
This Standard is a modified version of EN 145:19 97 (Respiratory protective  devices; Self-contained 
closed-circuit breathing apparatus; Compre ssed oxygen or compressed oxygen-nitrogen type; 
Requirements, testing, marking) of the European Committee for Standardization, the main technical 
differences are as follows: 
− the mass for 2-hour oxygen breathing apparatus has been re-specified; 
− the technical requirements for negative pr essure oxygen breathing a pparatus have been 
removed; 
− chambers for mixing respiratory gases into br eathing bags and breathing chambers have 
been subdivided, and volumes for breathin g bags and breathing chambers have been 
specified respectively; 
− the oxygen supply ration has been re-specified; 
− the test method for surface resistan ce in Appendix A has been removed. 
 
Article 5.10, Article 5.11, Article 5.19, Article 5. 23, Article 5.24 and Article 5.25 of this Standard 
are mandatory.  This Standard is proposed by the State Administra tion of Work Safety of the People’s Republic of 
China.  This Standard is interpreted by and under the jurisdiction of the Na tional Safe Production 
Standardisation Technical Commission.  The following organisations participat ed in drafting this Standard:  
Shanxi Hong'an Science and Technology Co. Ltd; 
The Research Institute of Chemical Defence; Fushun Branch of China Coal Research Institute;  The main drafters of this Standard are:  Li Xiaoyin, Yu Jin, Li Xinnian, Jin Shouxiang, Li Xinwen and Yang Dongxing. 
  
 
 - 4 -            
Self-contained close-circuit breathi ng apparatus of compressed oxygen 
 
 1  Scope 
This Standard specifies the technical requirements, test met hods, classifications, inspection rules, 
markings, packaging, storage and transportation  requirements for self-contained closed-circuit 
compressed oxygen and compressed oxygen-nitrogen breathing apparatus.   This Standard applies to self-contained clos ed-circuit compressed oxygen and compressed oxygen-
nitrogen breathing apparatus with positive pressure  gas supplying modes (herei nafter referred to as 
oxygen breathing apparatus).  This Standard does not apply to negative pressu re oxygen breathing appa ratus, compressed air 
breathing apparatus, underwater breathing a pparatus and escape oxygen breathing apparatus. 
 2  Normative References 
The provisions of the following documents become  provisions of this Standard after being 
referenced. For dated reference documents, a ll later amendments (excluding corrigenda) and 
versions do not apply to this Standard; however, the parties to the agreem ent are encouraged to 
check whether the latest versio ns of these documents are applicable. For undated reference 
documents, the latest versions apply to this Standard.  GB/T 1226, General pressure gauges  GB/T 2410, Transparent plastics, transmiss itivity and haze test (EQV ASTM D1003:1977) 
 GB/T 2891-1995, Performance test methods fo r facepiece of filter type respirator 
 GB 3836.1-2000, Electrical apparatus for explosive gas atmospheres – Part 1:  General requirements 
(EQV IEC 60079-0:1998)  GB 3836.4–2000, Electrical apparatus for explosive gas at mospheres – Part 4: Intrinsic safety (EQV 
IEC 60079-11:1999)  GB 5009, Seamless steel gas cy linders (NEQ ISO 4075:1983) 
 GB 8982, Gaseous oxygen supplies for medicine  DOT CFFC Standard, Carbon- fibre aluminium cylinders 
 3  Terms and definitions  
 3.1 Self-contained close-circuit compresse d oxygen or compressed oxygen-nitrogen breathing 
apparatus 
A type of breathing apparatus which has a facepie ce for isolating the respiratory organ of the 
apparatus wearer from the harmful air of th e external environment; the apparatus carries 
compressed oxygen or compressed oxygen-nitrogen as  the breathing air source, and absorbs the 
carbon dioxide exhaled by the wearer thereof, whic h mixes with the oxygen then is supplied back to - 5 - the wearer to breathe, forming a complete respirat ory circulation. 
 3.2 Positive pressure self-contained clos e-circuit compressed oxygen or oxygen-nitrogen 
breathing apparatus 
A type of oxygen breathing apparatus. During a ny of the respiratory circ ulation processes, the 
pressure in the low pressure system is not lower than the environmental pressure. 
 3.3 High pressure system 
High pressure system refers to the high pressure gas path which is create d by high pressure oxygen 
bearing components such as high pressure oxygen cylinders, cylinder switche s, pressure reducers, 
manual replenishing valves, pressure indicators and alarm devices and their connectors, etc. 
 3.4 Medium pressure system 
Medium pressure system refers to the medium pressure gas path which is created by medium 
pressure oxygen bearing compone nts such as quantitative oxygen supply valves and automatic 
replenishing valves and their connectors, etc. 
 3.5 Low pressure system 
Low pressure system refers to the low pressure gas path which is create d by low pressure oxygen 
bearing components such as the facepiece, respir atory valve, respiratory hose, carbon dioxide 
absorption equipment, temperature cooler, exha ust valve and the breathing bag or breathing 
chamber etc. and their connectors. 
 4 Classifications and marks 
 4.1 Classifications  4.1.1 Classification on the basis of rated time-of-use: 
a) 1-hour positive pressure oxygen breathing apparatus, standard designation: 1; 
b) 2-hour positive pressure oxygen breathing apparatus, standard designation: 2; 
c) 3-hour positive pressure oxygen breathing apparatus, standard designation: 3; 
d) 4-hour positive pressure oxygen breathing apparatus, standard designation: 4. 
 4.1.2 Classification on the basis of the type of gas in the gas cylinder 
a) Oxygen breathing apparatus, standard designation: O 2; 
b) Oxygen-nitrogen mixture breathing appa ratus, standard designation: O 2N2. 
 4.2 Marks 
The product mark consists of the product name, number of this Standard, oxygen breathing 
apparatus classification, rated ti me-of-use and the classification of  the gas cylinder. See 4.1 for the 
standard designation of the classi fication and the standard designati on of the rated time-of-use for 
the oxygen breathing apparatus. The letters F, G and L represent carbon-fibre composite gas 
cylinders, steel gas cylinders and al uminium gas cylinders respectively. - 6 - Example 1: for a 4-hour positive pressure oxygen breathing apparatus, wh en using a carbon-fibre 
composite gas cylinder, the mark should be: 
Positive pressure oxygen breathing apparatu s GB xxxx (number of this Standard)-O 2-4-F 
The meanings of each element of  the mark are listed below: 
O2 – Oxygen breathing apparatus; 
4 – Indicates the rated tim e-of-use is four hours; 
F – Indicates the cylinder is  a composite gas cylinder. 
Example 2: for a 2-hour positive pressure oxygen-nitr ogen mixture breathing apparatus, when using 
a steel gas cylinder, the mark should be: 
Oxygen-nitrogen mixture breathing apparatu s GB xxxx (number of this Standard) -O 2N2-2-
G 
The meanings of each element in the label are as follows: 
O2N2 – Oxygen-nitrogen mixtur e breathing apparatus; 
2 – Indicates that the rate d time-of-use is two hours; 
G – Indicates that the contai ner is a steel gas cylinder. 
 5 Technical requirements 
 5.1 General provisions 
 5.1.1 With every test, all oxygen breathing apparatus which are being tested should meet the 
requirements specified in this Standard. 
 5.1.2 If no other rules are specified, when any of the clauses of this Standard are referenced, all of 
its sub-clauses should be referenced at the same time. 
 5.2 Ergonomic requirements 
The technical requirements of this Standard have taken into consideration the interactions between 
the wearer of any oxygen breath ing apparatus, the oxygen brea thing apparatus itself and the 
possible application places of  the breathing apparatus. - 7 -  5.3 Design requirements 
5.3.1 An oxygen breathing apparatus comprises a f acepiece, a gas cylinder, a purifying pot, a 
cooling tank, a breathing bag or a breathing chamber, shell, a body harness, a respiratory hose, a 
pressure reducer, a pressure indicator and a pressure alarm device, etc . 
5.3.2 The structure of any oxygen breathing apparatu s should be simple, compact, and convenient 
for performing inspections according to  the manufacturer’s instructions. 
5.3.3 Oxygen breathing  apparatus should be strong and reliable, should be able to withstand heavy 
usage and must be adaptive to the cla ssification of the oxygen breathing apparatus. 
5.3.4 Protruding components or parts on oxygen breathing apparatus are not permitted. If the wearer 
of the oxygen breathing apparatus passes though a narrow gap, any protruding parts of the oxygen 
breathing apparatus should not rest rict the person from passing through. 
5.3.5 Extruded parts or sharp corners on the shell of any oxygen breat hing apparatus are not 
permitted. There should not be any sharp edges or  burrs on the surfaces of the components which 
may come into contact with the we arer. The shells should be suffic iently strong, the backplates of 
the lower shells should meet the physiological cu rve of human back; and the clasp used to fix the 
upper and lower shells should have an appropriate degree of tightness and flexible unlocking so as 
to prevent accidental unlocking. 
5.3.6 The components of oxygen breathing apparatus which are to be operated by the wearers 
should be easy and comfortable to reach, and shoul d be identifiable by using your hands. None of 
the adjustable components or control valves should accidentally fluctuate during use. The 
installation position of the gas cylind er valve should be easy for the wearer to turn on/switch off the 
gas cylinder whilst it is in use. 
5.3.7 The oxygen breathing apparatus should maintain  their protective functi ons in any position. 
When an oxygen breathing apparatus is removed and the wearer is still wearing the facepiece, they 
should still be able to breathe from the oxygen breathing apparatus. 
5.3.8 The chemicals used in the oxygen breathing  apparatus and the ge nerated saliva and 
condensate water should not affect the normal func tions of the oxygen breathing apparatus or harm 
the user. 
5.3.9 The operations of the oxygen breathing a pparatus should be normal in the following 
circumstances: 
a) atmospheric pressure: 70 kPa ~ 125 kPa; 
b) relative humidity: 0% ~ 100%; 
c) environmental temperature: -20oC ~ +60oC. 
5.3.10 The components of oxygen breathing apparatus for training and the components of oxygen 
breathing apparatus for operational use cannot be exchanged. Clear identification marks should be 
provided; the components of oxygen breathing appa ratus for training cannot be assembled onto any 
oxygen breathing apparatu s for operational use. - 8 -  5.4  Material requirement s 
5.4.1 The materials selected for oxygen breathing a pparatus should have sufficient mechanical 
strength and should be anti-fatigue, anti-ageing and anti-corrosion. 
5.4.2 With the exception of the facepieces and respir atory hoses, the surface resistance for any other 
exposed components of oxygen breathing apparatus must not exceed 1x109 Ω. 
5.4.3 Aluminium, magnesium, titanium and their all oys must not be used as materials in the 
exposed components of oxygen breathing apparatus. 
5.4.4 The materials used for the oxygen breathing a pparatus which may come into direct contact 
with the breathing gases and the skin of the users should not be harmful to the health of the users. 
5.4.5 The oxygen contained in the gas cylinders shoul d meet the provisions set out in GB 8982, and 
the oxygen-nitrogen mixture contained in gas cylinders  should meet the requirements of all relevant 
national health regulations. 
5.4.6 The carbon dioxide absorbent should meet the following requirements: 
a) the absorption rate of carbon dioxi de should not be less than 30%; 
b) the water content should  be between 16% ~ 20%; 
c) the dust rate should not exceed 3%. 
d) the carbon dioxide content should not exceed 2.5%. 
 5.5 Cleaning and disinfection 
The materials used for oxygen breathing apparatus should be able to with stand anti-fogging agents, 
cleansers and disinfectants whic h are recommended by the manufact urer, and there should be no 
visible damage after being anti -fogged, cleaned and disinfected. 
 5.6 Mass 
The mass for the entire standby oxygen breathi ng apparatus unit equipped with facepiece and 
containing gas should meet the specif ications prescribed in Table 1. 
Table 1: Oxygen breathing apparatus mass 
Classification of the oxygen 
breathing apparatus Mass, kg 
1 ≤ 10 
2 ≤ 12 
3 ≤ 14 
4 ≤ 16 
 
 5.7 Connection 
 5.7.1 General requirements 
5.7.1.1 All components of oxygen breathing apparatus s hould be easy to disassemble, clean, check - 9 - and test. 
5.7.1.2 All disassembled parts should be easy to assemb le together; the assembly should be strong 
and reliable. The equipment may be assembled by hand. 
5.7.1.3 When disassembling any joints and connect ors during normal maintenance process, the 
applied sealing parts should not fall off or be displaced. 
 5.7.2 Connectors 
The connectors should prevent any unexpected di scontinuation of the gas source or gas path 
blockage. Under any distorted state, the respirat ory hose should not affect the connection of the 
connectors and the performance of  the oxygen breathing apparatus. 
 5.7.3 Bonding strength of the respiratory hose 
The bonding strength for the joint between the gas s upply system and the respiratory hose should be 
able to withstand an axial tension of 250 N for 10 seconds. 
 5.7.4 Connection between the gas supply system and the facepiece 
The connection methods between the respiratory hos e and the facepiece should be firm jointed, 
special jointed or thread jointed. 
 5.8 Facepiece 
5.8.1 The facepiece should cover the eyes , nose and mouth at the very least. 
5.8.2 The sealing frame of the facepiece should be f it closely to the wearer ’s face; the facepiece 
should be comfortable when worn over a long peri od and the leakage coefficient of the facepiece 
should not exceed 0.005%. 
5.8.3 The fixation system of the facepiece should be sufficiently strong, elastic and should be 
adjustable for the user. 
5.8.4 The visual field of the facepi ece should be wide, and objects s hould be clearly visible and not 
distorted. The total reservation ra tio of the visual field must not be less than 70%; the reservation 
ratio of the visual field for both eyes must not be  less than 55%. 
5.8.5 The transmisstancy for the lens of the facepiece should not be less than 85%. 
5.8.6 The facepieces should be adequately weather resi stant, able to be oper ated normally in hot and 
humid environments, and in particular have go od anti-fogging and anti-d imming performance at 
low temperatures. Effective anti-dimming duration should not be less than  the rated operation time 
of the oxygen breathing apparatus. 
5.8.7 The facepieces should have enough airtightness. Wh en the internal pressu re of a facepiece is 
(4.7 ± 0.5) kPa, the pressure decreasing in one  minute should not exceed 40 Pa; or, when the 
underwater airtightness inspection method is use d, no air bubbles should escape from any of the 
seals on the facepiece. 
5.8.8 The bonding strength between the facepiece and th e respiratory hose shoul d not be less than 
250 N. 
 5.9 Body harness 
5.9.1 The body harness should be easy for the wearer  to put the oxygen breathing apparatus on or - 10 - remove it quickly without any assistance from another person. The straps of the body harness 
should be adjustable, and should not unint entionally slide or be easily displaced. 
5.9.2 The user should not feel any discomfort or  be nervous when wearing an oxygen breathing 
apparatus when operating in a squatting position or in an environment with limited space. The 
oxygen breathing apparatus should cau se the least possible interfer ence to the activ ities of its 
wearer. 
 5.10 Inlet valve and outlet valve 
5.10.1 The valve assembly should be easy to mainta in and should not be assembled incorrectly. 
5.10.2 The components, parts and assembly of the in let valves and outlet va lves may be designed 
with the same structures and sizes, but should be clearly marked in order to be assembled easily and 
correctly. 
5.10.3 The reverse gas leakage of the inlet valve and outlet valve should not exceed 0.3 L/min. 
5.10.4 The ventilation resistance of the inlet va lve and outlet valve should not exceed 30 Pa. 
 5.11 Outlet valve 
5.11.1 General requirements 
5.11.1.1 The breathing gas path of any oxygen breat hing apparatus should be  equipped with an 
exhaust valve which relies on pre ssure to operate automatically. Th e exhaust valve can be operated 
normally in any direction, and can prevent dust from entering and mechanical damage. 
5.11.1.2 In the respiratory gas path, if the exhaust valve is to be opened be fore the carbon dioxide 
absorption tank, then the pr essure difference between the exhaust valve and the air intake po rt of the 
breathing bag should not exceed the opening pressure of the exhaust valve under any circumstances.  
5.11.2 Opening pressure If the gas flow is steady as 1.0 L/min when th e exhaust valve is in a ny direction, the opening 
pressure should not exceed 1 kPa. 
5.11.3 Reverse airtightness When the exhaust valve bears a pressure of 1 kPa from the opposite direction of the opening 
direction, the pressure decreasing in 1 minute sh ould not exceed 100 Pa. 
 5.12 Breathing bags and breathing chambers 
5.12.1 Breathing bags 
5.12.1.1 The materials selected for the breathing bags should be strong  and soft and should be able 
to prevent extrusion stress from external force. 
5.12.1.2 The breathing bags should be firmly attached  to the connectors. The joint type which is 
near the inlet side should ensure that the opening of the joint will not be closed by the breathing bag 
itself. 
5.12.2 Airtightness At a pressure less than 1 kPa, no gas s hould leak within the period of 1 minute. 
5.12.3 V olume 5.12.3.1 The effective volume for breathing ba gs should not be less than 5 L. - 11 - 5.12.3.2 The effective volume for breathing cham bers should not be less than 4 L. 
 5.13 Practical performance 
5.13.1 Oxygen breathing apparatus s hould be subject to practical simulation experiments under 
normal conditions. These practical experiments ar e used to inspect the defects of the oxygen 
breathing apparatus which ca nnot be detected under la boratory test conditions. 
5.13.2 During any activity, if the person performing the test is no t able to complete the designated 
activities due to the oxygen breathing apparatus’ inconformity with its setting application, or the 
oxygen concentration (volume concentration) in th e inhaled gas is less than 21%, and the carbon 
dioxide concentration (volume concentration) exceeds 3%, then this oxygen breathing apparatus 
should be classified as unsatisfactory. 
5.13.3 Once all the activities are completed, the pe rson performing the test should rate the 
following: 
a) the convenience of putting on/removing the oxygen breathing apparatus; 
b) the convenience of putting on/removing, locking, adjusting and the comfort of the head-
strap; 
c) the comfort of the facepiece; 
d) the size of the visual field; 
e) clear state of hearing and talking; 
f) clear state when looking through the facepiece window; 
g) skin irritation if any; 
h) the level of comfort of the shell and shell strap; 
i) the level of comfort and balance when wearing the device; 
j) how easily the connectors and st rap button lock into place; 
k) the accessibility of the pressure gauge and control valve when using your hands; 
l) the operability and effectiveness of the alarm device; 
m) the operability of the respiratory hose; 
n) the effect of the positioning of the respirator y hose in terms of the free movement of the 
head; 
o) the comfort of breathing (such as the te mperature, pressure and gas quantity); 
p) other opinions concerning the structure and materials used; 
q) other opinions reported by the pe rson testing the equipment. 
On the basis of the answers from the above questions, determine whether the oxygen breathing 
apparatus has met the requirements of the test. 
 5.14 The adaptability of the temperature, flame, thermal radiation and impact 
5.14.1 Temperature adaptability 
Within the temperature range of -15oC ~ 45oC, the oxygen breathing apparatus should operate 
without failure. - 12 - 5.14.2 Flame adaptability 
The facepiece with headband, resp iratory hose with connection and the body harness should all be 
flame retardant. The after-flame time must not exceed 5 seconds. 
5.14.3 Thermal radiation adaptability The facepiece with connection and th e respiratory hose should be subjected to a thermal radiation 
adaptability test for 20 minutes. Deformation after the test is permitted, but the items should still be 
able to maintain normal operation and the airt ightness of the parts should be maintained. 
5.14.4 Impact adaptability Following the impact test, packed oxygen breathi ng apparatus should still meet the requirements 
specified in 5.23 and 5.24. 
 5.15 The strength of the high-pressure co mponents and medium-p ressure components 
5.15.1 After being maintained at one and half times the rated operati on pressure of the gas cylinder 
for one minute, there should be no visible deform ation or leakage to the high-pressure metallic 
components. 
5.15.2 After being maintained at tw ice the rated operation pressure of the gas cylinder for five 
minutes, there should be no visible deformation or leakage to the high-pressure non-metallic 
components.  
5.15.3 After being maintained at twice the rated opera tion pressure of the ga s cylinder pressure for 
15 minutes, there should be no visible deformation or leakage to the medium-pressure components. 
 5.16 The interchangeability of the high-pre ssure, medium-pressure and low-pressure 
connectors 
The high-pressure, medium-pressure and low-pr essure connectors must not be interchanged. 
 5.17 Gas cylinder 
5.17.1 Steel gas cylinders should meet the requirements set out in GB 5099. 
5.17.2 Composite gas cylinders should meet the requ irements set out in DOT CFFC standards or 
rules set
 out in the relevant national standards. 
 5.18 Gas cylinder valve 
5.18.1 When the hand wheel on the gas cylinder valve is in normal operation, the valve core must 
not be completely removed from the valve. The opening direction of the gas cylinder valve should 
be anti-clockwise, and the number of the rotating cycles for the hand wheel from closed state to 
complete opening state should not be less than two cycles. 
5.18.2 Once the gas cylinder valv e has been opened it cannot be closed accidentally. 
5.18.3 The gas cylinder should be equipped with a blasting membrane, the blasting pressure of 
which should be (1.2 ~1.5) times of the rated operating pressure of the gas cylinder. - 13 -  5.19 Pressure reducer 
5.19.1 The adjustable components of any pressure redu cer should be firmly lock ed and any errors in 
adjustment should be observed. 
5.19.2 When the rated operating pressure  of the gas cylinder is up to  2 MPa, the deviation of the 
output pressure of the pressure re ducer should be within the range of ± 10% of the design pressure. 
5.19.3 The pressure reducer should be equipped with a safety valve; the opening pressure of the 
safety valve should be (1.1~2.0) times the maximu m output pressure; the out put flux should not be 
less than 100 L/min. 
 5.20 Pressure indicator 
5.20.1 When opening the gas cylinder valve, the pre ssure in the gas cylinde r should be readable. 
5.20.2 The installation position of the pressure gauge should be easy for the wearer to read the 
pressure value. 
5.20.3 The connecting pipeline of th e pressure gauge should be str ong and reliable and the outer 
shell should be equipped with  a rubber protection cover. 
5.20.4 The pressure gauge should be dust-proof and wa terproof, should be able to tolerate being 
submersed one metre under water fo r 24 hours. Once the test has been completed there should be no 
water inside the pressure gauge. 
5.20.5 The pressure value on the pressure gauge  should be easily readable in poor light. 
5.20.6 When the connecting pipeline of the pressu re gauge breaks off, the gas leakage under 20 
MPa pressure should not exceed 25 L/min. 
5.20.7 The pressure gauge window should be made of materials which do not produce fragments 
when broken. 
5.20.8 The mechanical pressure gauge should m eet the provisions se t out in GB/T1226, the 
minimum value of its measuring range is zero, th e maximum value of its measuring range should be 
5 MPa more than the rated operatio n pressure of the gas cylinder, the precision shoul d not be lower 
than 2.5 and the minimum scale division value should not exceed 1 MPa. 
5.20.9 The explosion-proof properties for electronic pressure gauges should meet the provisions of 
the Ex ia IIC T4 set out in GB3836.1-2000; the explosion-proof properties for the electronic 
pressure gauges of oxygen breathing apparatus fo r the mining industry should meet the provisions 
of the Ex ia I set out in GB3836.4-2000. 
 5.21 Pressure alarm device 
5.21.1 When opening or closing the gas cylinde r valve, an indicat ing alarm should sound. 
5.21.2 When the pressure of a gas cylinder has reduced  to (5.5± 0.5) MPa, th e alarm device should 
generate continuous sound or intermittent alarm sound, and the sound level should not be lower than 80 dB(A). The alarm duration should be  within the range of (30 ~ 60) seconds. 
5.21.3 The explosion-proof properties of the electroni c alarm devices should meet the provisions of 
the Ex ia IIC T4 set out in GB3836.1-2000; the explosion-proof prope rties for the electronic alarm 
devices of oxygen breathing apparatus for the mini ng industry use should meet the provisions of the 
Ex ia I set out in GB3836.4-2000. - 14 -  5.22 Respiratory hose 
5.22.1 Respiratory hoses should be  soft, with no distortion. 
5.22.2 Respiratory hoses should not interfere with  the movement of the head and should not 
generate any errors with the gas flow. 
5.22.3 Any permanent deformation of a respiratory hose should not exceed 10%. 
 5.23 Gas supply ration 
5.23.1 Oxygen supply ration 
When the pressure of the gas cylinder is the same as the rated operation pressure and reaches 2 
MPa, the oxygen supply ration shoul d not be less than 1.4 L/min. 
5.23.2 Automatic oxygen supply ration When the pressure in a breathing bag or a breathing chamber is 10 Pa ~ 245 Pa, the automatic 
supply valve should be opened; when the pressure of the gas cylinder is the same as the rated 
operation pressure and reaches 5 MPa, the automatic oxygen supply ration should not be less than 80 L/min. 
5.23.3 Manual oxygen supply ration When the pressure of the gas cylinder is the same as the rated operation pressure and reaches 5 
MPa, the manual oxygen supply ration should not be less than 80 L/min; when the pressure of the gas cylinder is equal to or less than 5 MPa, the oxygen supply ratio n should not be less than 16 x 
PL/min (here the P refers to the pressure va lue of the gas cylinder as indicated by MPa). 
 5.24 Airtightness 
5.24.1 High, medium pressure system airtightness 
High, medium pressure system in th e airtightness test should not result in any leakages within the 
space of two minutes. 
5.24.2 Low pressure system airtightness When the exhaust valve is closed, under a positive pressure of 750 Pa, the change of the pressure 
value should not exceed 30 Pa within one minute. When the exhaust valve is not closed, under a 
negative pressure of 750 Pa, the ch ange of the pressure value shoul d not exceed 80 Pa within one 
minute.   
 5.25 Respiratory physiological parameters 
5.25.1 General requirements 
2-hour oxygen breathing apparatu s should meet the technical requirements for 1-hour oxygen 
breathing apparatus, 3-hour oxygen breathing apparatus should meet the technical requirements for 
1-hour and 2-hour oxygen breathing apparatus, 4-hour oxygen breath ing apparatus should meet the 
technical requirements for 1-hour, 2-hour and 3-hour oxygen breathing apparatus. 
5.25.2 Rated protection time When using test equipment to simulate human breathing to test the device, the oxygen breathing 
apparatus should meet the corre sponding requirements for operation time. Within the rated 
operation time, the oxygen breathing apparatus s hould meet the requirements specified in 5.25.3, 
5.25.4, 5.25.5 and 5.25.6. - 15 - 5.25.3 Respiratory resistance 
The respiratory resistance of any oxygen breathing apparatus should meet the specifications stated 
in Table 2. 
Table 2: Respiratory resistance 
Respiration 
capacity 
L/min Respiratory rate 
min-1 Test duration, min Respiratory 
resistance 
60 
120 
180 30 20 
240 0~600 
30 (1-hour, 2-hours) 50 25 
60 (3-hours, 4-hours) 0~700 
75 30 5 0~1,000 
 
5.25.4 Oxygen content The oxygen content in the inhaled gases should no t be less than 21% (volume concentration). 
5.25.5 Inhaled gas temperature 5.25.5.1 Under the test temperat ure condition of (26± 2)
oC, if a temperature cooler is installed, then 
the temperature of the inha led gas should not exceed 35oC; when no temperature cooler installed, 
then the temperature of the inhaled gas should not exceed 45oC. 
5.25.5.2 Under the test temperat ure condition of (40± 2)oC, if a temperature cooler is installed then 
the temperature of the inha led gas should not exceed 40oC. 
5.25.6 Carbon dioxide content 5.25.6.1 The carbon dioxide content when the respira tion capacity is 50 L/min, according to Table 3 
to conduct the test, among which: 
a) when not wearing the facepiece, the carbon diox ide content in the inhaled gases should not 
exceed 1% (volume concentration); 
b) when the facepiece is included, the carbon dioxi de content in the inhaled gases should not 
exceed 1.5% (volume concentration). 
5.25.6.2 Carbon dioxide content at the end of the rated operation time 
Once the end of the rated operation time has ceased  and after the alarm device has started sounding, 
conduct the test according to Table 4. After the test , the carbon dioxide content in the inhaled gases 
should not exceed 3% (volume concentration). 
 6 Test methods 
 6.1 General requirements 
 6.1.1 When there is no special purpose testing in strument, and methods are specified in this - 16 - Standard, common instruments and conve ntional test methods can be used. 
 6.1.2 Facepieces should be included in the oxygen breathing apparatus test. 
 6.2  Nominal value and tolerance 
6.2.1 Unless otherwise specified, the numerical values stated in this Standard are the theoretical 
correction values. With the exception of temperature limits, the tolerance of all other parameters, the maximum and minimum values of which are not  mentioned in this Standard, shall be 5%. 
6.2.2 Unless otherwise specified, the envir onmental temperature for the test is 16
oC ~ 32oC, the 
tolerance of the temperature limits is ± 1oC. 
 6.3 Visual inspection 
6.3.1 Before conducting laboratory and practical te sts, the oxygen breathing apparatus should be 
visually inspected and disassembled in accordance with the maintenance manual. 
6.3.2 The visual inspection should include the proving materials which are relative to the marks of 
the oxygen breathing apparatus, the information provided by the manufacturers, safety data or the 
materials used for the structures. 
 6.4 Practical performance test 
6.4.1 General requirements 
6.4.1.1 Two oxygen breathing appa ratus, four wearers. 
6.4.1.2 The wearers should be healthy males between 18 and 35 year old, who should have practical 
experience of using oxygen breathin g apparatus. The wearers should undergo routine health checks 
such as an electrocardio gram, heart rate and blo od pressure checks. Before  testing, the name, age, 
sex, height and weight of each wearer should be recorded. 
6.4.1.3 The oxygen breathing apparatus used for the test should have passed the laboratory test. 
Before testing, the oxygen breathing apparatus should be tested to ensure they are in good working 
order. The pressure of the oxygen cylinder at the be ginning of the test should be the rated operation 
pressure. 
6.4.1.4 The test should be conducted in an area of natural light, with a temperature in the range of 
16oC ~ 32oC and relative humidity of 30% ~ 80%, the temp erature, humidity and noise level in the 
duration of the test should be recorded. 
6.4.2 Operation simulation test The tests of the oxygen breathing apparatu s should be conducted under normal operating 
conditions. In this test, the followi ng tasks should be completed in order to simulate the practical 
applications of the oxygen breathing apparatus. 
a) Train 30 times on an exercise machine, using a ro pe or a pulley mechanism to vertically lift 
a 25 kg load from the ground to a height of 1.8 m. 
b) Walk on a flat surface with complete headroom  clearance; the total walking distance should 
be 125 m. 
c) Walk on a flat surface with a headroom clearan ce of (1.3± 0.2) m for 5 minutes (the total - 17 - walking distance should be approximately 140 m); 
d) Crawling on a flat surface with a headroom cl earance of (0.7 ± 0.05) m for 5 minutes (the 
total crawling distance shoul d be approximately 70 m); 
e) Climb up a ladder, and go through a square open ing with a horizontal length of 460 mm, and 
total vertical height of 20 m. Repeat when climbing back down the ladder; 
f) Climb over a narrow area with a width of (0.7 ± 0.05)  m and a length of 4 m. In this area the 
wearers should remove the oxygen breathing apparatu s, but still be able to breathe using the 
oxygen breathing apparatus. Under such conditio ns, the wearers place the oxygen breathing 
apparatus in the front to push or place the oxygen breathing apparatus behind to pull. 
g) Deploying and retracting a fire distri bution hose with a length of 15 m. 
The tests should be conducted continuously and the oxygen breathing a pparatus must not be 
removed. See Table 3 for the test duration and the number of the test for each class of the oxygen 
breathing apparatus. 
Table 3: The test duration and the number of  the test for the operation simulation of oxygen 
breathing apparatus 
Test cycle Classification of 
the oxygen 
breathing 
apparatus Number of the test Duration, min Total test duration, min 
1 3 20 60 
2 5 24 120 
3 6 30 180 
4 8 30 240 
 6.5 Temperature adaptability test 
6.5.1 Laboratory test with ventilator 
6.5.1.1 Storage tests at the temperature of -20oC and 60oC 
Place an oxygen breathing apparatus which contains  the gas cylinder and the facepiece in an 
environment with a temperature range of (-20± 3)oC for 12 hours. Next, place the oxygen breathing 
apparatus in an environment with  a temperature range of (60± 3)oC and a relative humidity not 
greater than 50% for 12 hours. According to the guidelines specified in Section 6.9.2, at a 
temperature range of (30± 1)oC, conduct the test with a respirat ory flow of 50 L/min to the oxygen 
breathing apparatus. The ventilator and facepiece should be placed outside of the temperature 
control chamber. 
6.5.1.2 Storage test at a temperature of -6oC 
Place an oxygen breathing apparatus which contains  the gas cylinder and the facepiece in an 
environment with a temperature range of (-6± 2)oC for 12 hours. According to the guidelines 
specified in Section 6.9.2, at a temperature range of (-6± 2)oC, conduct the test with a respiratory 
flow of 50 L/min to the oxygen br eathing apparatus. The ventilator  and facepiece should be placed 
outside of the temperat ure control chamber. 
6.5.2 Low temperature practical performance test 6.5.2.1 Low temperature test af ter it has been stored at room temperature  - 18 - 6.5.2.1.1 Preparation of the test equipment 
6.5.2.1.1.1 The oxygen breathing apparatus should be subj ected to the cleaning and disinfection in 
accordance with the methods recommended by the manufacturers. 
6.5.2.1.1.2 Two standby oxygen breathing apparatus should be placed in an environment with a 
room temperature range of (16oC ~32oC) for 2 to 3 hours. 
6.5.2.1.2 Test procedures Two individuals, wearing heat re tention clothing, put on the oxygen breathing apparatus at a room 
temperature range of (16
oC ~ 32oC) and enter into a freezing room with the temperature range of (-
6± 2)oC. The test should be conducted continuous ly for 30 minutes. Duri ng the test, the oxygen 
breathing apparatus must not be removed. Each st age of the operating duration is five minutes, 
according to the requirements repeat the operation: 
a) walking; 
b) crawling; 
c) carrying blocks, etc. (mass of 7 kg) move 6 metres, and stack the blocks in accordance with 
the model illustrated in Diagram 1. 
d) use a rope to pull a lo ad with a mass of 50 kg. 
Once the test is completed, check and determine wh ether there is any damage  or operation disorder 
with the oxygen breath ing apparatus caused by the low temperature. 
Diagram 1: Block model 
6.5.2.2 Test at a temperature of -6oC 
6.5.2.2.1 Preparation of the test equipment 6.5.2.2.1.1 The oxygen breathing apparatus should be cleaned and disinfected in accordance with 
the methods recommended by the manufacturers. 
6.5.2.2.1.2 Two standby oxygen breathing apparatus should be placed in an environment with a 
room temperature range of (-6± 2)
oC for 2 to 3 hours. 
6.5.2.2.2 Test procedures The two individuals conducting th e test, wearing heat reten tion clothing, put on the oxygen 
breathing apparatus in the freezing room, carry out the operation in th e freezing room at a 
temperature of (-6± 2) 
oC. The test should be conducted conti nuously for 30 minutes  in accordance 
with the test procedures specified in 6.5.2.1.2. Duri ng the test, the oxygen brea thing apparatus must 
- 19 - not be removed. 
Once the test is completed, the individuals shoul d check whether there is any damage to or 
operation disorder of the oxygen breathing apparatus caused by the low temperature. 
 6.6 Performance test of alarm devices   
Alarm devices should be subjected to a test with the following procedures: 
a) when opening the gas cylinder valve, listen to  the indicating sound of the alarm device; 
b) close the gas cylinder valve and adjust the respiratory rate of the ventilator to 10 times/min. 
Once the respiratory flow is 10 L/min, test  the performance of the alarm device; 
c) use a sound level meter and a st opwatch to determine the sound intensity of the alarm device 
and the alarming duration at a distance of one  metre from the oxygen breathing apparatus. 
 6.7 Performance test of respiratory hoses 
Hang up a respiratory hose vertically, measure its length (excluding the conn ector) (length a). Apply 
a force load of 10 N onto the hose for 48 hours, rem ove the load, after having recovered for 6 hours 
and measure its length (length b). Calculate the permanent deformation rate (b-a)/a%. 
 6.8 Gas supply ration test 
6.8.1 An oxygen breathing apparatus detector is selected as the test instrument. 
6.8.2 Determination of th e oxygen supply ration. 
When the internal pressure of the high pressu re system of the oxygen breathing apparatus are 
(20~18)MPa and (3~2)MPa respectively, use the oxygen breathing apparatus detector to measure 
the oxygen supply ration respectively. 
6.8.3 Determination of the opening pressure for automatic supply and the determination of the 
automatic oxygen supply ration.  
6.8.3.1 The internal pressure of the high pressure  system of any oxygen breathing apparatus should 
be (20~2)MPa, place the oxygen breathing apparatu s horizontally, at the interface port of the 
facepiece, use the oxygen breathing apparatus detector to suck the gas with a flow rate of (8~12) 
L/min from the low pressure system, observe the indication value of the pressure gauge when the 
automatic supply valve is  opened to supply oxygen. 
6.8.3.2 When the internal pressure of the high pressure system of  the oxygen breathing apparatus 
are (20~18)MPa and (3~2)MPa respectively, us e the oxygen breathing apparatus detector to 
measure the oxygen supply ration respectively. 
6.8.4 Determination of the manual oxygen supply ration.  When the internal pressure of the high pressu re system of the oxygen breathing apparatus are 
(20~5)MPa and (5~2)MPa respectively, use the oxyge n breathing apparatus detector to measure the 
oxygen supply ration. 
 6.9 Respiratory physiological parameter test 
6.9.1 Respiratory resistance measurement 
6.9.1.1 Measuring instruments are a ventilat or and an inertialess pressure gauge 
6.9.1.2 Adjust the respiratory flow of the ventilator to the numerical values stated in Table 2. - 20 - 6.9.1.3 Connect the oxygen brea thing apparatus directly onto the ventilator. Use the inertialess 
pressure gauge to determine the respiratory resi stance at the connection of the oxygen breathing 
apparatus and the ventilator. Th e resistance caused by the connector  at the connection should be 
subtracted from the determined value. 
6.9.1.4 When testing, the gas cylinder valve s hould be completely opened. The oxygen supply 
ration should be directly inducted into the respirat ory gas path. Use an auxiliary pump to remove 
5% of the exhaled gas. 
6.9.1.5 If the measured value is incr eased due to the opening of th e automatic supply valve or the 
opening of the exhaust valve, then this va lue should be valid and should be adopted. 
6.9.2 Content measurement of oxygen, carbon dioxide in inhaled gases and the temperature test. 
6.9.2.1 See Diagram 2 for the test device, which cons ists of a ventilator, two check valves (for 
inhalation and exhalation use resp ectively), a heat exchanger (see Diagram 3), a humidifier (see 
Diagram 4), connections, a carbon dioxide flow c ontroller, a carbon dioxid e analyser and an oxygen 
analyser, two temperature measur ing devices and a manometer. 
 
1-Ventilator; 2-Auxiliary pump (ven tilator control); 3-Valve system;  
4-Control valve (ventilator c ontrol); 5-Thermocouple; 6-H eating elements (thermocouple 
control); 7-Humidifier (see Di agram 4); 8-Heat exchanger (see Diagram 3); 9-Cooler;  
10-Condensate collection vessel;  
11-Cooling water inlet port and outlet port; 12-Carbon dioxide  analyser (exhalation);  
13-Carbon dioxide control and measurement system; 14-Carbon dioxide gasometer;  
15-Carbon dioxide balancing bag; 16-Check valve; 17-Gas sampling gasometer;  
- 21 - 18-Oxygen analyser; 19-Carbon dioxide an alyser and recorder (inhalation);  
20-Temperature measuring device; 21-Conn ector;  22-Oxygen breathing apparatus;  
23-Manometer. 
Diagram 2: Schematic diagram of test device for simulation of human breath  
 
1-Ventilator interface;  2-Cooling water inlet port;  3-Cooli ng water outlet port; 
4-Water level overflow interface; 5-Control valve interfaces. 
Diagram 3: Schematic diagram of heat exchanger 
6.9.2.2 A test device allows an oxyge n breathing apparatus to main tain respiratory circulation 
through a ventilator, under a condition with a relative humidity range of (95~100)% and a 
temperature range of (37± 0.5)oC , the gas flow should meet the sp ecific values stated in Table 4 
and Table 5. 
6.9.2.3 Input carbon dioxide gas into the ventilator through the control and measurement system, 
the balancing bag and both of the check valves. 
Table 4: Carbon dioxide content 
Classification 
of the oxygen 
breathing 
apparatus  Respiration rate Input quantity of 
carbon dioxide 
L/min Carbon 
dioxide content in exhaled gas 
% Test 
duration 
Hour 
1 
2 
3 
4 Respiratory 
frequency 25 times/min  Respiratory flow 50 L/min 2.5 5.0 1 
 
- 22 - Table 5: Carbon dioxide content 
Classification 
of the oxygen breathing apparatus  Respiration rate Input 
quantity of carbon dioxide 
L/min Carbon dioxide 
content in exhaled gas 
% Test 
duration Hour 
1 Respiratory 
frequency 25 times/min Respiratory flow 50 L/min 2.5 5.0 1 
2 Respiratory 
frequency 25 times/min Respiratory flow 50 L/min 2 5.0 2 
3 Respiratory 
frequency 25 times/min Respiratory flow 50 L/min 1.35 4.5 3 
4 Respiratory 
frequency 25 times/min Respiratory flow 50 L/min 1.35 4.5 4 
 
 
- 23 - 1-Ventilator interface;  2-Fluid infusion device;  
3-Thermocouple (control heating elemen ts);  4-Control valve interface;  
5-Heating elements (250~300 W); 
Diagram 4: Schematic diagram of humidifier 
6.9.2.4 At the outlet port of the humidifier, use a sampling pipe to continuously pump out a small 
amount of exhaled gas and put into a carbon dioxide analyser, then back from the inlet port of the 
humidifier. 
Diagram 3 is a schematic diagram for a heat exchanger with a volume of 500 ml ~ 1,000 ml; the 
heat exchanger should maintain a water flow rate of 3 L/min. 
Diagram 4 is the schematic diagram for a humidifier. The total volume for the gas path of a test system  (ventilator is excluded) should not exceed 2,000 
ml. 
The airtightness of the gas path for a test system: at a pressure of 2,000 Pa, the pressure decreasing 
value in one minute should not exceed 98 Pa. 
The test should be conducted in a room e nvironment with a temper ature range of (16~32)
oC and a 
relative humidity range of (85~95)%. 
Before starting the test, the temperature of th e exhaled gases should be checked and adjusted. 
During the test process, in order to measure the content of the carbon dioxide and oxygen in the 
inhaled gases at the inhalation stage use an aux iliary pump to drain a suitable amount of inhaled 
gases from the marked location (see Diagram 2), feed  the gases into the oxyge n analyser and carbon 
dioxide analyser. The content of the oxygen in th e pumped gases should correspond with the input 
quantity of carbon dioxide stated in  Table 4. Once the analysis is completed, the residual nitrogen 
and carbon dioxide should be fed back into the re spiratory gas path. The te st should last until the 
gases in the oxygen breathing appa ratus are completely depleted. 
6.9.2.5 Use a fast response thermocouple digital th ermometer to measure the temperature of the 
inhaled gases. 
6.9.2.6 Continuously measure and record the oxygen content, carbon dioxide content, temperature 
and respiratory resistance of the inhaled gases. 
 6.10 Binding strength test of the respiratory hose 
Install and adjust the connecting place of the respiratory hose, ma ke sure the connecting place can 
withstand the axial tension for ce. Apply a tension of 250 N to the connecting place, and check 
whether there is a ny trace of damage. 
 6.11 Facepiece performance test 
6.11.1 The performance tests for the leakage coefficients of the face pieces should be conducted in 
accordance with the provisions se t out in Article 3.1 of GB2891-1995. 
6.11.2 The performance tests for the visual fiel ds of the facepieces should be conducted in 
accordance with the provisions se t out in Article 3.3 of GB2891-1995. 
6.11.3 The performance test for the transmittan ce of the facepieces should be conducted in - 24 - accordance with the provisions set out in GB/T2410. 
6.11.4 The performance test for the airtightness of the facepieces should be conducted in accordance 
with the provisions set out in Article 3.4 of GB2891 -1995. 
 6.12 Flame adaptability 
6.12.1 See Diagram 5 for the test equipment of flame adaptability. The testing equipment consists of 
a propane gas cylinder which is equipped with a fl ow control valve, valve,  pressure regulator, 
pressure gauge, backfire eliminator, sample hold er and burner nozzle. The purity of the propane 
should not be lower than 95%. 
6.12.2 Place the test sample material in the flam e which is produced by propane gas to conduct the 
test. The air valve of the burner noz zle should be closed completely. Ad just the flame height to (40± 
4) mm by adjusting the supply of the propane gas, the measured flame temperature at a distance of 
(20± 2) mm from the burner nozzle should be (800± 50)oC. The test sample should be positioned 
horizontally in the flame where it is (20± 2)  mm higher than the burner nozzle for (12± 0.5) 
seconds. Ensure that the centre area of th e flame touches the edge of the sample. 
 
1-Propane gas cylinder; 2-Valv e; 3-Pressure regulator;  
4-Pressure gauge; 5-Backfire e liminator; 6-Sample holder;  
7-Flame; 8-Partition panel; 9-Nozzle 
Diagram 5: Test equipment for flame resistance 
 6.13 Impact adaptability test 
Attach a packed oxygen breathing a pparatus onto the impact testi ng machine. After continuously 
testing the oxygen breathing apparatu s with an acceler ation of 30 m/s2 and rotation frequency of 
(80~120) r/min for two hours, determine the ga s supply ration, the re spiratory physiological 
parameters and the airtightne ss in accordance with Article 6.8, Article 6.9 and Article 6.21. 
 6.14 Gas reverse leakage test for inlet valve and outlet valve 
6.14.1 The measuring instruments and equipment include  a micro pressure gauge, a rotameter, a wet 
gasometer and a stopwatch. 
- 25 - 6.14.2 Reverse connect the in let valve or outlet valve onto the testing equipment, pumping in a 
stable gas flow with a flow rate of 1.5 L/min, main tain the ventilation pressure at 1 kPa, measure 
the leakage quantity in a 1 minute time period. 
 6.15 Ventilation resistance test of  inlet valve and outlet valve  
6.15.1 The measuring instruments are a micro pressure gauge and a rotameter. 
6.15.2 Connect the inlet valve and outlet valve onto the measuring devices, pump in a stable gas 
flow with a flow rate of (30~31) L/min, and obs erve the pressure value on the micro pressure 
gauge. 
 6.16 Opening pressure test for exhaust valve 
6.16.1 The measuring instrument is an oxygen breathing apparatus detector. 
6.16.2 Positioning the oxygen breathi ng apparatus horizontally, stan ding upright, standing upside 
down and positioned freely, supply oxygen with a flow rate of 1.0 L/min to the low pressure system, use the oxygen breathing apparatus detector to dete rmine the opening pressure of the exhaust valve. 
 6.17 Volume test of breathing bag or breathing chamber 
6.17.1 The measuring instruments and equipment co mprise an oxygen breathing apparatus detector, 
wet gasometer, suction pump and a gas collection bag with a volume of 10 L. 
6.17.2 Remove the respiratory hose from the oxygen br eathing apparatus, seal up the exhaust valve, 
the gas cylinder valve and the inte rface of the respiratory hose. Use the suction pump to extract the 
gases from the breathing bag or the breathing chamber and use the oxygen breathing apparatus 
detector to determine the suction pressure. 
6.17.3 Establish a 750 Pa positive pressure in the breat hing bag or breathing chamber, then start the 
suction until it reaches a negative pressure of 500 Pa. Collect into  the gas collecti on bag using the 
wet gasometer to determine the volume. 
 6.18 Performance test for pressure reducer 
6.18.1 The measuring instruments are a rotameter and a precision pressure gauge. 
6.18.2 When inputting (20~3) MPa pressure from the high pressure end of th e pressure reducer, use 
the rotameter to measure the output flow; gradually in crease the internal pressure  of the safety valve  
using the pressure gauge to dete rmine the opening pressure, and use the rotameter to measure the 
gas leakage of the safety valve. 
 6.19 Airtightness test  for exhaust valve  
6.19.1 The measuring instruments comprise an oxyge n breathing apparatus detector, a constant 
volume cavity with a volume of 500 ml and a stopwatch. 
6.19.2 Reverse connect the exhaust valve onto the cons tant volume cavity, establish 1 kPa pressure 
in the cavity using a stopwatch and observe the pr essure decreasing value in a 1 minute time period. 
 6.20 Airtightness test for breathing bag or breathing chamber 
6.20.1 The measuring instruments comprise an oxygen breathing appara tus detector and a 
stopwatch. - 26 - 6.20.2 Establish 1,000 Pa pressure inside the breath ing bag or breathing chamber using a stopwatch 
and observe the changes of  the pressure value. 
 6.21 Airtightness test 
6.21.1 Airtightness of the high, medium pressure system 
Establish a pressure of (20~18)  MPa inside the high, medium pressure system of the oxygen 
breathing apparatus, smearing soap liquid at the join t of the high pressure sy stem. Check if there is 
any gas leakage within a 2 minute period. 
6.21.2 Airtightness of low pressure system Close the exhaust valve of the oxygen breathing appara tus, establish a pressure of 750 Pa inside the 
low pressure system using the stopwatch and observe  the decreasing value of the pressure in a one 
minute time period. Do not close the exhaust valv e of the oxygen breathing apparatus. Establish a 
pressure of 750 Pa inside the lo w pressure system using the stopw atch and observe the decreasing 
value of the pressure within a one minute time period. 
 7 Inspection rules 
 7.1 Inspection classifications 
The inspection is divided into type inspection and factory inspection, according to 7.2 and 7.3 to 
conduct the inspection respectively. 
 7.2 Type inspection 
Products in any one of the following situati ons should be subject to type inspection: 
a) the pattern evaluations of the trial production of any new product or any existing products 
which are manufactured in a different factory; 
b) when there are significant changes to the raw materials, designs, processes and production 
equipment of any normally produced pr oduct effecting the product quality; 
c) any continuous normal production for three years or any continuous production reaching 
300 product units; 
d) the product has been out of production for more than a year, then production is restarted; 
e) products which are requested by the National In stitute for Product Quality Supervision for  
Type Inspection. 
 7.2.1 Type inspection 
The items of the type inspection should be conducted in accordance with Table 6. 
 7.2.2 Sample size 
Samples for the type inspection should be randoml y selected from the products which qualify from 
the factory inspection. The sample size is three units. 
 7.2.3 Product volume 
The product volume should not be less than 30 units. - 27 -  7.2.4 Qualification determination 
When all of the inspection items of the type inspection for a produc t completely conform to this 
Standard, then this product can  be regarded as qualified. 
 7.3 Factory inspection 
Completely assembled oxygen breathing apparatus s hould be subject to insp ections carried out by 
the manufacturer’s quality control department. Once the products have  qualified from the inspection 
and have been issued with the product quality cer tificate, they are then permitted to leave the 
factory. 
 7.3.1 Inspection items 
Refer to Table 6 for the inspection items. 
 7.3.2 Sample size of sampling inspection 
The sample size is three units. 
 7.3.3 Determination rules 
When all of the inspection items of the factory inspection for a pr oduct completely conform to this 
Standard, then the product can be regarded as qualified. See Table 6 for the type inspection items 
with regard to the inspection results of the samples. If any of the units does not qualify, a re-inspection should be carried out wi th double the sample size. If th e item inspection still fails to 
qualify from the re-inspection, then the product should be regarded as unsatisfactory. If more than 
one item from the unit sample fails to qualify fr om the inspection, then the product should be 
regarded as unqualified. 
Table 6: Inspection Items 
Factory inspection 
Serial 
number Technical 
requirements clause Technical 
requirements item Unit by unit 
inspection Sampling 
inspection Type 
inspection Commen
ts 
1 5.3 Design 
requirements - - √   
2 5.4 Material 
requirements - - √   
3 5.5 Cleaning and 
disinfection - - √   
4 5.6 Quality - √  √   
5 5.7 Connection √  √  √   
6 5.8 Facepiece - - √  ∆ 
7 5.9 Back carrier - √  √  ∆ 
8 5.10 Inlet valve 
and outlet valve √  √  √  ∆ 
9 5.11 Exhaust valve √  √  √   - 28 - 10 5.12 Breathing bag 
or breathing chamber - - √  ∆ 
11 5.13 Practical 
performance - - √   
12 5.14 Temperature, 
flame and thermal radiation adaptability - - √   
13 5.15 Strength of 
high pressure and medium pressure components - - √   
14 5.16 Interchangea
bility of high pressure, medium pressure and low pressure connectors - √  √   
15 5.17 Gas cylinders √  √  √  ∆ 
16 5.18 Gas cylinder 
valve √  √  √  ∆ 
17 5.19 Pressure 
reducer √  √  √   
18 5.20 Pressure 
indicator √  √  √  ∆ 
19 5.21 Pressure 
alarm device √  √  √  ∆ 
20 5.22 Respiratory 
hose √  √  √  ∆ 
21 5.23 Gas supply 
ration √  √  √   
22 5.24 Airtightness √  √  √   
23 5.25 Respiratory 
physiological parameters √  √  √   
Note: item with “ √” means an inspection item; item w ith “-” means a non-inspection item; 
item with “ ∆” means a component. 
 - 29 -  8 Symbols, packaging, transportation and storage 
 8.1 Labelling 
Every unit of oxygen breathing apparatus should be cl early labelled with the following information: 
a) name of the product and the registered trademark; 
b) type or mark of the product; 
c) the number and implementation year of this Standard; 
d) date of manufacture (or number) and batch number; 
e) quality grade or safety  certification mark; 
f) warning marks or warnings; 
g) product origin, manufacturer's name, fu ll address, postcode and phone number. 
 8.2 Packaging 
8.2.1 Each unit of the oxygen breath ing apparatus should have it s designated packaging box. The 
packaging box should be clean an d dry, shockproof and press re sistant. Materials which may 
corrode the oxygen breathing apparatus and material s which may generate harmful gases must not 
be used for the packaging. 
8.2.2 Moisture preventative measures should be adopt ed for the inside of the packaging boxes; 
disassembled packed parts should be placed appr opriately in the box, reasonably laid out using 
fixation measures. 
8.2.3 The facepieces should be packaged individually and the lenses of the facepieces should be 
subject to protective measures. 
 8.3 Transportation 
8.3.1 Any means of transportation can be selected to transport the oxygen breathing apparatus. 
8.3.2 When the oxygen breathing apparatus are being transported, there should be no collision or 
heavy load. The method of transportation should be waterproof, sunlight-proof; when transported as 
general goods, then the gas cylinders  should be empty. If the gas cy linders are transported in a gas 
loaded state, they should conform to the rules of the relevant trans portation departments. 
 8.4 Storage 
8.4.1 The oxygen breathing apparatus should be stor ed in rooms which are clean, dry and well 
ventilated. 
8.4.2 During storage, the oxygen breathing apparatus should be placed in packaging boxes avoiding 
long-term direct sunlight. 
8.4.3 The oxygen breathing apparatus must not be stor ed with oils, acids, alkalis or corrosive 
substances.