KENYA STANDARD  KS 2170 -1: 
2022 
ICS 11.040.10  
Second Edition  
  
 © KEBS 2022   
 Medical gases — Specification    
Part 1: 
Part title  Medical oxygen   
 
 
KS 2170 -1: 20 22  
ii © KEBS 2022  – All rights reserved  
 TECHNICAL COMMITTEE REPRESENTATION  
The following organizations were represented on the Technical Committee:  
Consumer Information Network  
BOC Kenya Ltd.  
Noble Gases International Ltd.  
Chemigas Ltd.  
Government Chemist’s Department  
Kenya Industrial Research and Development Institute (KIRDI)  
Kenyatta University — Chemistry Department  
Kenya Science Teachers College  
Ministry of Roads — Materials Branch  
Kenya Industrial Estate  
Kenya Medical Association  
Kenyatta National Hospital  
Ministry of Medical Servi ces 
Kenya Bureau of Standards — Secretariat  
REVISION OF KENYA STANDARDS  
In order to keep abreast of progress in industry, Kenya Standards shall be regularly reviewed.  Suggestions for 
improvements to published standards, addressed to the Managing Director,  Kenya Bureau of Standards, are 
welcome.  
© Kenya Bureau of Standards, 2022  
Copyright. Users are reminded that by virtue of Section 25 of the Copyright Act, Cap. 130 of 2001 of  the Laws of Kenya, copyright subsists 
in all Kenya Standards and except as provi ded under Section 25 of this Act, no Kenya Standard produced by Kenya Bureau of Standards 
may be reproduced, stored in a retrieval system in any form or transmitted by any means without prior permission in writing f rom the 
Managing Director.   KENYA STANDARD  KS 2170 -1: 
2022 
ICS 11.040.10  
Second  Edition  
 
© KEBS 2022  – All rights reserved  iii 
  Medical gases  — Specification   
Part n: 1 
Part title  Medical oxygen  
Kenya Bureau of Standards,  Popo Road, Off Mombasa Road,  
P.O. Box 54974 - 00200,  Nairobi, Kenya  
 +254 020 6948000, + 254 722202137, + 254 734600471  
 info@kebs.org  
 @KEBS_ke  
 kenya  bureau of standards (kebs)  
  
KS 2170 -1: 20 22  
iv © KEBS 2022  – All rights reserved  
 Foreword  
This Kenya Standard was prepared by the Gases  Technical Committee under the guidance of the Standards 
Projects Committee, and it is in accordance with the procedures of the Kenya Bureau of Standards  
Medical oxygen c overed in this standard is intended for use in the medical sector and this standard cover 
characteristics touching on their safety, packaging and marking. The presence of odour in medical oxygen 
results in discomfort to users of breathing equipment and thi s standard addresses this aspect as well.  
Medical oxygen covered by this standard is intended for inhalation. The standard specifies limits on impurities 
such as carbon monoxide, carbon dioxide, oil, oxidizing substances and water.  
Identity, purity and acidity requirements are also covered in this standard.  
This second … edition cancels and replaces the first/… edition (KS 2170 -1:2009 ), which has been technically 
revised.  
 
KS 2170 -1:2009  consists of the following parts, under the general title Medical ga ses — Specification :  
⎯ Part 1: Medical oxygen  
⎯ Part [2]: Medical Air  
⎯ Part [3]: Medical Nitrous oxide  
During the preparation of this standard, reference was made to the following document (s):  
International Pharmacopoeia, Fourth Edition, 2006, Monographs, Pharmaceutical substances — Oxygen 
Monograph  
International Pharmacopoeia, Fourth Edition, 2006 Reagents — Reagents, test solutions and volumetric 
solutions.  
British Pharmacopoeia online 2008 — Gas detector tubes (Ph. Eur. text 2.1.6)  
 United St ates Pharmacopoeia (USP), 22ND Revision, 1990, official Monographs — Oxygen.  
 ISO 10083:2006, Oxygen concentrator supply systems for use with medical gas pipeline systems.  
Acknowledgement is hereby made for the assistance derived from this (these) source ( s) 
The foreword  shall appear in each standard. It shall not contain requirements, figures or tables.  
In addition to the appropriate text (see above  in red ) give the designation and name of the committee that 
prepared the standard, together with as many of the following as are appropriate:  
— an acknowledgement of the publication (s)  that has or have been widely referred to in the  preparation of 
the standard;  
— a statement that the standard cancels and replaces other documents in whole or in part;  
— a stateme nt of significant technical changes from the previous edition of the standard;  
— the relationship of the standard to oth er standards or oth er documents  
 KS2170 -1: 20 22  
© KEBS 2022  – All rights reserved  v 
  Contents  Page 
Foreword  ................................ ................................ ................................ ................................ ...................  iv 
Introduction  ................................ ................................ ................................ ................................ ...............  vi 
1 Scope  ................................ ................................ ................................ ................................ .............  1 
2 Normative references  ................................ ................................ ................................ ...................  1 
3 Terms and definitions  ................................ ................................ ................................ ..................  2 
4 Symbols (and abbreviated terms)  ................................ ................................ ...............................  2 
5 Clause  ................................ ................................ ................................ ................................ ............  3 
5.1 Subclause (level  1) ................................ ................................ ................................ .......................  3 
5.1.1  Subclause (level  2) ................................ ................................ ................................ .......................  3 
5.1.2  Subclause (level  2) ................................ ................................ ..........  Error! Bookmark not defined.  
5.2 Subclause (level  1) ................................ ................................ ..........  Error! Bookmark not defined.  
6 Clause  ................................ ................................ ...............................  Error! Bookmark not defined.  
6.1 A level  1 subclause without a title.  ................................ ................  Error! Bookmark not defined.  
6.1.1  A level 2 subclause without a title.  ................................ ................  Error! Bookmark not defined.  
6.1.2  A level  2 subclause without a title.  ................................ ................  Error! Bookmark not defined.  
6.2 A level  1 subclause without a title.  ................................ ................  Error! Bookmark not defined.  
7 Special  ................................ ................................ ..............................  Error! Bookmark not defined.  
Annex  A (normative)  Annex title  ................................ ................................ ................................ .............  4 
A.1 General  ................................ ................................ ................................ ................................ ..........  4 
A.2 Clause  ................................ ................................ ................................ ................................ ............  4 
A.2.1  Subclause (level  1) ................................ ................................ ..........  Error! Bookmark not defined.  
A.2.2  Subclause (level  1) ................................ ................................ ..........  Error! B ookmark not defined.  
A.3 Clause  ................................ ................................ ................................ ................................ ............  4 
Bibliography  ................................ ................................ ................................ ................................ .............  12 
 
The table of contents is an optional preliminary element, but is necessary if it makes the document easier to 
consult. The table of contents shall be entitled “Contents” and shall list clauses and, if appropriate, subclauses 
with titles, annexes together with their status in parentheses, the bibliography, indexes, figures and tables. 
The order shall be as follows: clauses and subclauses with titles; annexes (including clauses and subclauses 
with titles if appropriate); the bibliography; indexes; figures; tables. All the elements listed shall be cited with 
their full titles. Terms in the “Terms and definitions” clause shall not be listed in the table of contents.  
The table of contents shall be inserted for a document of 15 or more pages.  KS 2170 -1: 20 22  
vi © KEBS 2022  – All rights reserved  
 Introduction  
A paragraph.  
The introduction is an optional preliminary element used, if required, to give specific information or 
commentary abo ut the technical content of the document, and about the reasons prompting its preparation. It 
shall not contain requirements.  
The introduction shall not be numbered unless there is a need to create numbered subdivisions. In this case, it 
shall be numbered 0, with subclauses being numbered 0.1, 0.2, etc. Any numbered figure, table, displayed 
formula or footnote shall be numbered normally beginning with 1.  
 KENYA STANDARD  KS 2170 -1: 20 22 
 
© KEBS 2022  – All rights reserved  1 
 Medical gases — Specification  
Part n: 1 
Part title  Medical Ox ygen  
1 Scope  
This Part 1 of KS 2170 prescribes the requirements and test methods for compressed medical oxygen intended 
for inhalation.  
The Scope clause shall appear at the beginning of each document and define without ambiguity the subject of 
the documen t and the aspects covered, thereby indicating the limits of applicability of the document or 
particular parts of it. It shall not contain requirements.  
In documents that are subdivided into parts, the scope of each part shall define the subject of that part of the 
document only.  
The scope shall be brief and precise  so that it can be used as a summary for bibliographic purposes.  
It shall be worded as a series of statements of fact. Forms of expression such as “This Kenya  Standard 
specifies [establishes] [ gives guidelines for] [defines terms]  …” shall be used.  
Statements of applicability of the document shall be introduced by the wording such as “This Kenya  Standard 
is applicable to  …”. The wording shall be altered as a function of the document type concern ed, i.e. Kenya  
Standard,  Kenya National Workshop Agreement,  Technical Specification, Publicly Available Specification, 
Technical Report or Guide.  
A clause is the basic component in the subdivision of the content of a document.  
The clauses in each document or part shall be numbered with Arabic numerals, beginning with 1 for the 
“Scope” clause. The numbering shall be continuous up to but excluding any annexes. Numbers given to the 
clauses of an annex shall be preceded by the letter designating that a nnex followed by a full -stop. The 
numbering shall start afresh with each annex.  
Each clause shall have a title, placed immediately after its number, on a line separate from the text that 
follows it.  
A paragraph is an unnumbered subdivision of a clause or s ubclause.  
“Hanging paragraphs” (see ISO/IEC Directives, Part  2) shall be avoided since reference to them is 
ambiguous.  
2 Normative references  
. 
The following referenced documents referred to in the text in such a way that some or all of their content 
const itutes requirements of this document. For dated references, only the edition cited applies. For undated 
references, the latest edition of the referenced document (including any amendments) applies.  
The following standards contains provisions which, through  reference in this text, constitute provisions of this 
standard. For undated reference, the latest edition of the normative document referred to applies.  
 KS ISO 32, Gas cylinders for medical use — Marking for identification of content  KS 2170 -1: 20 22  
2 © KEBS: 2022 : – All rights reserved  
  KS ISO 7225, Gas cy linders — Precautionary labels  
 KS 09 -532, Specification for standard atmospheric conditions for test purposes  
3 Terms and definitions  
For the purposes of this document, the following terms and definitions apply.  
3.1 
R reagent  
3.2 TS test solution  
3.3 VS volumetric solutions or solutions that are similarly standardized  
STP standard atmospheric temperature and pressure as per KS 09 -532  
 
  
4 Requirements ) 
4.1 When tested in accordance with the method specified in Annex A, the product shall have a minimum of 
93%±3 v/v oxygen content.  
4.2 Identity When tested in accordance with the method specified in Annex B, the product shall pass the test.  
4.3 Oxidizing substances When tested in accordance with the method specified in Annex E, the product shall 
pass the test.  
4.4 Acidity and alkalinity When tested in accordance with the method specified in Annex F, the product shall 
pass the test  
4.5 Odour When tested in accordance with the method specified in Annex H, the product shall pass the test.  
4.6 Impurities The product shall be colourless and sh all comply with the impurities limits given in Table 1.  
                                            Table 1 — Impurity limits for medical oxygen  
SL No.  Characteristic  Requirement  Test method  
i) Carbon monoxide, ppm 
v/v, max                5 Annex C  
ii) Carbon dioxide ppm v/v, 
max              300 Annex D  
iii) Water ppm v/v, max.                60 Annex G  
iv) Oil mg/m ᵌ , max.            0.1 Annex J  
 KS 2170 -1: 20 22 
© KEBS 2022  – All rights reserved  3 
 5 Packaging and marking  
5.1 Packing ) 
The product shall be supplied as compressed gas or liquid at cryogenic temperature, in appropriate steel 
cylinders complying with relevant Kenya standards. Valves or taps shall not be lubricated with oil or grease.  
5.2 Marking ) 
5.2.1 Cylinder ) 
Each cylinder shall be clearly and indelibly marked with the following in formation:  
a) the words “Medical Oxygen”;  
 b) the name or registered trade mark and address of the manufacturer;  
 c) purity;  
 d) the impurities limits in Table 1, as applicable;  
 e) batch number; and,  
 f) date of filling; and, g) filling pressure (at STP).  
5.2.2  Colour and chemical formula  
Each cylinder shall in addition to the markings in 5.2.1, be clearly and indelibly marked with the colour and 
chemical formula corresponding to oxygen as specified in KS ISO 32.  
5.2.3 Precautionary labels  
Each cylinder shall in addition to the markings in 5.2.1, be clearly and indelibly marked with precautionary labels 
as specified in KS ISO 7225.  
 
. KS 2170 -1: 20 22  
4 © KEBS: 2022 : – All rights reserved  
 Annex  A 
(normative)  
 
Determination of oxygen content  
A.1 Principle  
This method covers the determination of oxygen content by means of a gas burette test.  
A.2 Apparatus  
A.2.1  25-mL capacity gas burette ( Fig. 1 ) 
A.2.2  A cylindrical funnel . 
A.3 Reagents  
A.3.1 Freshly prepared potassium hydroxide solution (~560 g/L ) TS 
 A solution of potassium hydroxide R containing about 560 g of KOH per litre.  
A.3.2 Freshly prepared sodium dithionite solution (200 g/l) TS  
 A solution of sodium dithionite R containing about 200 g of Na2O4S2 per litre.  
A.4. Procedure  
A.4.1  For the d etermination, use a 25 -mL capacity gas burette (Fig. A.1) in the form of a chamber with at its 
upper end, a tube graduated in 0.2 % between 95 and 100, and isolated at each end by a tap with a conical 
barrel. The lower tap is joined to a tube with an olive -shaped nozzle and is used to introduce the test gas into 
the apparatus. A cylindrical funnel above the upper tap is used to introduce the absorbent solution.  
A.4.2  Wash the burette with water and dry. Open the two taps. Connect the nozzle to the container  of the test 
gas and set the flow rate to 1 L per minute. Flush the burette by passing the gas through it for 1 min. Close the 
upper tap of the burette and immediately afterwards the lower tap. Rapidly disconnect the burette from the 
container of the test gas, and give a half turn to the upper tap to eliminate any excess pressure in the burette.  
A.4.3  Keeping the burette vertical fill the funnel with a freshly prepared mixture of 21 mL of potassium hydroxide 
(~560 g/L) and 130 mL of sodium dithionite (200 g/L). Open the upper tap slowly. The solution absorbs the 
oxygen and enters the burette. Allow to stand for 10 min without shaking.  
A.4.4  Read the level of the liquid meniscus on the graduated part of the burette and record the figure. The 
recorded figure represents the content of oxygen as a percentage in v/v.  
DIAGRAM  
Figure A.1 — Gas burette used for  the assay of oxygen  KS 2170 -1: 20 22 
© KEBS 2022  – All rights reserved  5 
  
                                                                  Annex B  
                                                                 (normative)  
                                                                 Identity test method  
B.1 Principle  
This method covers the determination of identity of oxygen by means of glowing splinter and alkaline pyrogallol 
tests.  
B.2 Reagent  
B.2.1 Alkaline pyrogallo l TS 
 Dissolve 0.5 g of pyrogallol R in 2 mL of water. Dissolve separately 12 g of potassium hydroxide R in 8 mL of 
water. Immediately before use mix the two solutions.  
B.3 Materials  
B.3.1 A splinter of wood  
B.4 Procedure  
B.4.1  Place a glowing splinter of wood into the test gas. The splinter shall bursts into flame.  
B.4.2  Shake the test gas with alkaline pyrogallol. The test gas shall be absorbed and the solution becomes dark 
brown (distinction from dinitrogen oxide).  
B.4.3  The test gas shall be deemed to h ave passed identity test if the splinter burst into flame as per B.4.1 and 
the solution becomes dark brown as per B.4.2.  
                                                                                 Annex C  
                                                                            (normative)  
                                                          Determination of carbon monoxide content  
C.1 Principle  
This method covers the determination of carbon monoxide content of oxygen using a carbon monoxide det ector 
tube.  
Gas detector tubes are cylindrical, sealed tubes consisting of an inert transparent material and are constructed 
to allow the passage of gas. They contain reagents adsorbed onto inert substrates that are suitable for the 
visualization of the su bstance to be detected and, if necessary, they also contain preliminary layers and/or 
adsorbent filters to eliminate substances that interfere with the substance to be detected.  
 The layer of indicator contains either a single reagent for the detection of a given impurity or several reagents 
for the detection of several substances (monolayer tube or multilayer tube).  
The test is carried out by passing the required volume of the gas to be examined through the indicator tube. 
The length of the coloured layer or the intensity of a colour change on a graduated scale gives an indication of KS 2170 -1: 20 22  
6 © KEBS: 2022 : – All rights reserved  
 the impurities present. The calibr ation of the detector tubes is verified according to the manufacturer's 
instructions.  
C.2 Apparatus  
C.2.1 Carbon monoxide detector tube  
A cylindrical, sealed glass tube containing adsorbent filters and suitable supports for di -iodine pentoxide, 
selenium di oxide and fuming sulphuric acid indicators (Figure C.2). The minimum value indicated is 5 ppm or 
less, with a relative standard deviation of at most ± 15 %. Tubes can be verified with a calibration gas containing 
the appropriate impurity, if a negative res ult is obtained.  
DIAGRAM  
Figure C. 2 — Apparatus for gas detector tube  
C.3 Reagents  
C.3.1 Calibration gas mixtures  
 C.4 Procedure  
 C.4.1  Verify the calibration of the detector tube according to the manufacturer's instructions.  
 C.4.2  The gas supply is conn ected to a suitable pressure regulator and needle valve. Connect the flexible 
tubing fitted with a Y -piece to the valve and adjust the flow of gas to be examined to purge the tubing in order 
to obtain an appropriate flow (Figure C. 2).  
 C.4.3  Prepare the i ndicator tube and fit to the metering pump, following the manufacturer's instructions.  
C.4.4  Connect the open end of the indicator tube to the short leg of the tubing and operate the pump by the 
appropriate number of strokes to pass a suitable volume of g as to be examined through the tube.  
 C.4.5  Read the value corresponding to the length of the coloured layer or the intensity of the colour on the 
graduated scale and report this as the carbon monoxide content. If a negative result is achieved, indicator tu bes 
can be verified with a calibration gas containing the appropriate impurity.  
                                                               Annex D  
                                                              (normative)  
                                                   Determination of carbon dioxide content  
D.1 Principle  
This method covers the determination of carbon dioxide content of oxygen using a carbon dioxide detector tube.  
Gas detector tubes are cylindrical, seal ed tubes consisting of an inert transparent material and are constructed 
to allow the passage of gas. They contain reagents adsorbed onto inert substrates that are suitable for the 
visualization of the substance to be detected and, if necessary, they also contain preliminary layers and/or 
adsorbent filters to eliminate substances that interfere with the substance to be detected.  
The layer of indicator contains either a single reagent for the detection of a given impurity or several reagents 
for the detectio n of several substances (monolayer tube or multilayer tube).  
The test is carried out by passing the required volume of the gas to be examined through the indicator tube. 
The length of the coloured layer or the intensity of a colour change on a graduated sc ale gives an indication of 
the impurities present. The calibration of the detector tubes is verified according to the manufacturer's 
instructions  KS 2170 -1: 20 22 
© KEBS 2022  – All rights reserved  7 
 D.2 Apparatus  
D.2.1 Carbon dioxide detector tube  
A cylindrical, sealed glass tube containing adsorbent filters  and suitable supports for hydrazine and crystal violet 
indicators (Figure D.3). The minimum value indicated is 100 ppm or less, with a relative standard deviation of 
at most ± 15 %. Tubes can be verified with a calibration gas containing the appropriate i mpurity, if a negative 
result is obtained.  
Diagram  
Figure D. 3 — Apparatus for gas detector tube  
D.3 Reagents  
D.3.1 calibration gas mixtures  
D.4 Procedure  
D.4.1  Verify the calibration of the detector tube according to the manufacturer's instructions.  
D.4.2  The gas supply is connected to a suitable pressure regulator and needle valve. Connect the flexible tubing 
fitted with a Y -piece to the valve and adjust the fl ow of gas to be examined to purge the tubing in order to obtain 
an appropriate flow (Figure D. 3).  
D.4.3  Prepare the indicator tube and fit to the metering pump, following the manufacturer's instructions.  
D.4.4  Connect the open end of the indicator tube to  the short leg of the tubing and operate the pump by the 
appropriate number of strokes to pass a suitable volume of gas to be examined through the tube.  
D.4.5  Read the value corresponding to the length of the coloured layer or the intensity of the colour o n the 
graduated scale and report this as the carbon dioxide content. If a negative result is achieved, indicator tubes 
can be verified with a calibration gas containing the appropriate impurity.  
                                                                             Annex E  
                                                                            (normative)  
                                                              Oxidizing substances test method  
E.1 Principle  
This method covers oxidizing substa nces test for oxygen.  
E.2 Apparatus  
E.2.1  Hermetically closed flat -bottomed glass cylinder — (with dimensions such that 50 mL of liquid reaches a 
height of 12 cm to 14 cm) that is fitted with:  
 (i) a delivery tube terminated by a capillary 1 mm in internal  diameter and placed within 2 mm of the bottom of 
the cylinder; and  
(ii) an outlet tube.  
E.3 Reagents  
E.3.1 Starch R, potato starch R or corn starch R  
E.3.2 Potassium iodide R, KI.  KS 2170 -1: 20 22  
8 © KEBS: 2022 : – All rights reserved  
 E.3.3 Freshly prepared starch TS  
Mix 0.5 g of starch R or of soluble star ch R with 5 mL of water, and add this solution, with constant stirring, to 
sufficient water to produce about 100 mL; boil for a few minutes, cool, and filter.  
E.3.4 Freshly prepared potassium iodide/starch TS1  
Dissolve 10 g of potassium iodide R in 95 mL of water and add to it 5 mL of starch TS.  
E.3.5 Glacial acetic acid R , CH4O2; d ~ 1.048.  
E.3.5 Glacial acetic acid R, C 2H4O2; d ~ 1.048.  
E.4 Procedure  
E.4.1 To two cylinders (see clause E.2) add 50 mL of freshly prepared potassium iodide/starch TS1 and about 
0.2 mL of glacial acetic acid R. Protect the cylinders from light.  
E.4.2  Pass 5.0 L of the test gas into one of the solutions and compare the colour produced.  
E.4.3  The gas shall be considered to have passed the test if solutions in both cylinders remain colourless.  
                                                                         Annex F  
                                                                       (normative)  
                                                           Acidity and alkalinity test method  
F.1 Principle  
This method covers acidity and alkalinity test for oxygen.  
 F.2 Apparatus  
F.2.1 Hermetically closed flat -bottomed glass cylinder  — (with dimensions such that 50 mL of liquid reaches 
a height of 12 -14 cm) that is fitted with:  
 i) a delivery tube terminated by a capillary 1 mm in internal diameter and placed within 2 mm of the bottom of 
the cylinder; and ii) an outlet tube.  
 F.3 Reagents  
 F.3.1 Ethanol (~750 g/l) TS , ethanol (95 %) R  
F.3.2 Ethanol (~375 g/l) TS , a solution of about 210 mL of ethanol (~750 g/L) TS diluted with water to 1 000 
mL. 
 F.3.3 Methyl red R , 4'-Dimethylaminoazobenzene -2-carboxylic acid, C 15H15N3O2 
 F.3.4 sodium hydro xide (0.05 mol/l) VS , sodium hydroxide R, dissolved in water to contain 2.000 g of NaOH 
in 1 000 mL  
 F.3.4.1 Method of standardization  
 Ascertain the exact concentration of the 0.05 mol/L solution in the following manner: Dry about 5 g of potassium 
hydroge n phthalate R at 105 °C for 3 h and weigh accurately. If the potassium hydrogen phthalate is in the form 
of large crystals, they should be crushed before drying. Dissolve in 75 mL of carbon -dioxide -free water R and 
titrate with the carbonate -free sodium hy droxide solution, using phenolphthalein/ethanol TS as indicator. Each KS 2170 -1: 20 22 
© KEBS 2022  – All rights reserved  9 
 0.204 2 g of potassium hydrogen phthalate is equivalent to 1 mL of carbonate -free sodium hydroxide (1 mol/L) 
VS. Standard solutions of sodium hydroxide should be re -standardized frequent ly. 
 F.3.5 methyl red /ethanol TS as indicator  
 Dissolve 25 mg of methyl red R in a mixture of 0.95 mL of sodium hydroxide (0.05 mol/L) VS and 5 mL of 
ethanol (~750 g/L) TS, warm the solution slightly and after cooling dilute with sufficient ethanol (~375 g/L) TS to 
produce 250 mL  
 F.3.6 Hydrochloric acid (0.01 mol/L) VS  
 Hydrochloric acid (~250 g/L) TS, diluted with water to contain 0.3647 g of HCl in 1 000 mL.  
 F.3.6.10 Method of standardization  
 Ascertain the exact concentration of the 0.01 mol/L solutio n in the following manner: Dissolve about 1.5 g, 
accurately weighed, of anhydrous sodium carbonate R, previously dried at 270 °C for 1 h, in 50 mL of water 
and titrate with the hydrochloric acid solution, using methyl orange/ethanol TS as indicator. Each 5 2.99 mg of 
anhydrous sodium carbonate is equivalent to 1 mL of hydrochloric acid (1 mol/l) VS.  
F.3.7 Carbon -dioxide -free water R  
 Purified water that has been boiled vigorously for a few minutes and protected from the atmosphere during 
cooling and storage.  
 F.4 Procedure  
F.4.1  Pass 2.0 L of the test gas through a mixture of 0.10 mL of hydrochloric acid (0.01 mol/L) VS and 50 mL 
of carbon -dioxide -free water R contained in cylinder specified in F.2.  
 F.4.2  For reference solution 1, use 50 mL of carbon -dioxid e-free water R contained in cylinders specified in 
F.2. For reference solution 2, use a mixture of 0.20 mL of hydrochloric acid (0.01 mol/L) VS and 50 mL of 
carbon -dioxide -free water R contained in cylinder specified in F.2.  
 F.4.3  To each solution add 0.1  mL of methyl red/ethanol TS.  
 F.4.4  The gas shall be considered to have passed the test if the intensity of the colour in the solution of the test 
gas is between those of reference solutions 1 and 2.  
                                                                                  Annex G  
                                                                                 (normative)  
                                                                            Determination of water content  
G.1 Principle  
This method covers the determination of wat er content of oxygen using a water vapour detector tube.  
Gas detector tubes are cylindrical, sealed tubes consisting of an inert transparent material and are constructed 
to allow the passage of gas. They contain reagents adsorbed onto inert substrates tha t are suitable for the 
visualization of the substance to be detected and, if necessary, they also contain preliminary layers and/or 
adsorbent filters to eliminate substances that interfere with the substance to be detected.  
 The layer of indicator contains  either a single reagent for the detection of a given impurity or several reagents 
for the detection of several substances (monolayer tube or multilayer tube).  
 The test is carried out by passing the required volume of the gas to be examined through the in dicator tube. 
The length of the coloured layer or the intensity of a colour change on a graduated scale gives an indication of KS 2170 -1: 20 22  
10 © KEBS: 2022 : – All rights reserved  
 the impurities present. The calibration of the detector tubes is verified according to the manufacturer's 
instructions.  
G.2 Appar atus 
 G.2.1 Water vapour detector tube  
Sealed glass tube containing adsorbent filters and suitable supports for the magnesium perchlorate indicator. 
The minimum value indicated is 60 ppm or less, with a relative standard deviation of at most ± 20 % Figure  G. 
4).Tubes can be verified with a calibration gas containing the appropriate impurity, if a negative result is 
obtained.  
DIAGRAM  
Figure G. 4 — Apparatus for gas detector tube  
G.3 Reagents  
 G.3.1 Calibration gas mixtures  
 G.4 Procedure  
 G. 4.1  Verify the calibration of the detector tube according to the manufacturer's instructions.  
 G.4.2  The gas supply is connected to a suitable pressure regulator and needle valve. Connect the flexible 
tubing fitted with a Y -piece to the valve and adjust the flow of gas t o be examined to purge the tubing in order 
to obtain an appropriate flow (Figure G. 4).  
 G.4.3  Prepare the indicator tube and fit to the metering pump, following the manufacturer's instructions.  
G.4.4  Connect the open end of the indicator tube to the shor t leg of the tubing and operate the pump by the 
appropriate number of strokes to pass a suitable volume of gas to be examined through the tube.  
G.4.5  Read the value corresponding to the length of the coloured layer or the intensity of the colour on the 
graduated scale and report this as the water content. If a negative result is achieved, indicator tubes can be 
verified with a calibration gas containing the appropriate impurity.  
                                                                    Annex H  
                                                                   (normative)  
                                                            Test method for odour  
H.1 Principle  
The method uses the principle of human olfactory detection system of odour in oxyge n. 
 H.2 Procedure  
 H.2.1  Carefully open the container valve of the test gas to produce a moderate flow of gas.  
 H.2.2  Do not direct the gas stream toward the face, but deflect a portion of the stream toward the nose.  
 H.2.3  The gas shall be deemed to have passed the test if no appreciable odour is discernible  
 
 KS 2170 -1: 20 22 
© KEBS 2022  – All rights reserved  11 
                                                                          Annex J  
                                                                       (normative)  
                                                             Determination of oil content  
J.1 Principle  
This method covers the determination of oil co ntent of oxygen using oil detector tube.  
 Gas detector tubes are cylindrical, sealed tubes consisting of an inert transparent material and are constructed 
to allow the passage of gas. They contain reagents adsorbed onto inert substrates that are suitable f or the 
visualization of the substance to be detected and, if necessary, they also contain preliminary layers and/or 
adsorbent filters to eliminate substances that interfere with the substance to be detected.  
 The layer of indicator contains either a single  reagent for the detection of a given impurity or several reagents 
for the detection of several substances (monolayer tube or multilayer tube).  
 The test is carried out by passing the required volume of the gas to be examined through the indicator tube. 
The length of the coloured layer or the intensity of a colour change on a graduated scale gives an indication of 
the impurities present. The calibration of the detector tubes is verified according to the manufacturer's 
instructions.  
J.2 Apparatus J.2.1 Oil d etector tube Sealed glass tube containing adsorbent filters and suitable supports for 
the sulphuric acid indicator (Figure 5). The minimum value indicated is 0.1 mg/m3 with a relative standard 
deviation of at most ± 30 %. Tubes can be verified with a calib ration gas containing the appropriate impurity, if 
a negative result is obtained.  
DIAGRAM  
Figure J. 5 — Apparatus for gas detector tube  
J.3 Reagents  
 J.3.1 Calibration gas mixtures  
 J.4 Procedure  
 J.4.1  Verify the calibration of the detector tube according to the manufacturer's instructions.  
 J.4.2  The gas supply is connected to a suitable pressure regulator and needle valve. Connect the flexible tubing 
fitted with a Y -piece to the valve and adjust the f low of gas to be examined to purge the tubing in order to obtain 
an appropriate flow (Figure J. 5).  
J.4.3  Prepare the indicator tube and fit to the metering pump, following the manufacturer's instructions.  
 J.4.4  Connect the open end of the indicator tube  to the short leg of the tubing and operate the pump by the 
appropriate number of strokes to pass a suitable volume of gas to be examined through the tube.  
J.4.5  Read the value corresponding to the length of the coloured layer or the intensity of the colo ur on the 
graduated scale and report this as the oil content. If a negative result is achieved, indicator tubes can be verified 
with a calibration gas containing the appropriate impurity.  KS 2170 -1: 20 22  
12 © KEBS: 2022 : – All rights reserved  
 Bibliography  
[1] ISO ##### -#, General title — Part #: Title of part  
[2] ISO ##### -##:20##, General title — Part ##: Title of part  
A Bibliography , if present, shall appear after the last annex.  
The bibliography may include  
— documents that are not publicly available,  
— documents which are only cited in an informative manner, and  
— documents which have merely served as bibliographic or background material in the preparation of the 
document.  
For online referenced documents, information sufficient to identify a nd locate the source shall be provided. 
Preferably, the primary source of the referenced document should be cited, in order to ensure traceability. 
Furthermore, the reference should, as far as possible, remain valid for the expected life of the document. T he 
reference shall include the method of access to the referenced document and the full network address . 
 KS 2170 -1:2022   
 
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