KENYA STANDARD  DKS 2970: 2022  
ICS 23.040.01; 91.140.80  
First  Edition  
 
 © KEBS 2022  
 Polypropylene (PP) pipe fittings for soil, 
waste and vent applications for above -
ground use  — Specification  
 
 DKS 2970: 2022  
ii © KEBS 2022 – All rights reserved  
 TECHNICAL COMMITTEE REPRESENTATION  
The following organizations were represented on the Technical Committee:  
Advance Plastics Ltd.  
Altek/ Sunace  
Apex Piping Ltd.  
General Industries Ltd.  
Isole engineering  
Kingspipe Ltd.  
Krona Plastics  Limited  
Pipe Masters  
Qatar Plastics  Industries Ltd  
Tile & Carpet  Ltd. 
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 provided under Section 25 of this Act, no Kenya Standard produced by Kenya Bureau of Sta ndards 
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  DKS 2970: 2022  
ICS 23.040.01; 91.140.80  
First  Edition  
 
© KEBS 2022 – All rights reserved  iii 
 Polypropylene (PP) pipe fittings for soil, waste 
and vent applications for above -ground use  — 
Specification  
 
 
  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)  
DKS 2970: 2022  
iv © KEBS 2022 – All rights reserved  
 Foreword  
This Kenya Standard was prepared by the Plastic Pipes and Fittings Technical Committee under the guidance 
of the Standards Projects Committee, and it is in accordance with the procedures of the Kenya Bureau of 
Standards.  
With the technological development in the Indu stry coupled with innovation, polypropylene pipes and fittings are 
coming in handy for use in the plastic industry.  
During the preparation of this Standard, reference was made to the following documents:  
KS ISO 7671:2003; Polypropylene pipes and fittings ( jointed by means of elastomeric sealing rings) for soil 
and waste water discharge (Low and high temperature) systems inside buildings - Specifications  
SANS 721:2018; Polypropylene (PP) pipe fittings for soil, waste and vent applications for above -ground 
use 
Acknowledgement is hereby made for the assistance derived from these sources.  
 
 DKS 2970: 2022    
  
© KEBS 2022 – All rights reserved   
 Polypropylene (PP) pipe fittings for soil, waste  and vent applications for 
above -ground use  — Specification  
 
1 Scope   
This Draft Kenya Standard specifies dimensions, sealing method and test methods for  polypropylene (PP) pipe 
fittings of nominal sizes 32mm to 200mm intended for above -ground non -pressure applications for the 
conveyance of soil (human excrement or faeces) and waste water where continuous temperatures in excess of 
60°C are not encountered.   
This standard is applicable to polypropylene (PP) pipe fittings with an integral socket to be jointed by means of 
hot glue gun . 
2 Normative references  
The following referenced documents  are referred to in the text in such a way that some or all of their content 
constitutes 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 . 
ISO 13264 , Thermoplastics piping systems for non-pressure underground drainage and sewerage — 
Thermoplastics fittings — Test method for mechanical strength or flexibility of fabricated fittings  
ISO 580 , Plastics piping and ducting systems — Injection -moulded thermoplastics fittings — Methods for 
visually assessing the effects of heating  
ISO/TR 7024 , Above -ground drainage — Recommended practice and techniques for the installation of 
unplasticized polyvinyl chloride (PVC -U) sanitary pipework for above -ground systems inside buildings  
3 Terms and definiti ons 
For the purposes of this document, the following definitions, symbols and abbreviations apply.  
ISO and IEC maintain terminological databases for use in standardization at the following addresses:  
— ISO Online browsing platform: available at http://www.iso.org/obp  
3.1 
nominal size  
nominal inside diameter of the body of the main limb or, in the case of a reducer, the combination of the nominal 
sizes of the large and small ends  
3.2  
pipe fitting  
fitting  
component that is used to so connect pipes as to form a soil and waste water installation  
3.3  
polypropylene (PP)  
material based on the monomer propylene to which are added those additives needed to facilitate the 
manufacture of components that comply wit h the requirements of this standard   
© KEBS 2022 – All rights reserved  iii 
 NOTE  Polypropylene is type PP -H (homopolymer) or type PP -B (block copolymer) or type PP -R (random copolymer).  
4 Abbreviations  
DN/ID  Nominal inside diameter/ Inside diameter  
PP Polypropylene  
5 Material  
5.1 Base materi al  
5.1.1  The base material shall be polypropylene (PP).  
5.1.2  The use of non -PVC piping in drainage installations may entail additional material design requirements . 
5.2 Melt mass -flow rate  
Pipe fittings shall be made from PP materials with an MFR (230/ 2, 16) ≤ 0.25 g/10 min for pipe fittings.  
5.3 Resistance to ultraviolet radiation  
The fittings shall be sufficiently stabilized against thermal ageing and ultraviolet (UV) light.  
5.4 Resistance to temperature cycling  
The test assembly used shall meet th e requirements given in annex D.  
Annex E specifies the information to be provided in the test report.  
6 General characteristics  
6.1 Appearance  
When viewed without magnification, the pipe fittings shall comply with the following requirements:  
a) the internal and external surfaces shall be smooth, clean and free from grooving, blistering, impurities, 
pores and any other surface irregularity likely to prevent compliance with this standard; and  
b) their ends shall be square to their axis.  
6.2 Colou r  
The pipe fittings shall be coloured through the whole wall.  
7 Geometrical characteristics  
7.1 Dimensions of pipe fittings  
7.1.1 Inside diameter  
The mean inside diameter of the fitting shall be in accordance  with Table 1 . 
  
iv © KEBS 2022 – All rights reserved  
 Table 1 — Mean inside diameters  
S/No.  Nominal size  
(mm) Nominal Inside 
diameter  
(mm) Mean inside diameter D  
mm 
Minimum  Maximum  
a)  32 32 32.3 32.5 
b)  40 40 40.3 40.5 
c)  50 50 50.3 50.5 
d)  63 63 63.3 63.5 
e)  75 75 75.3 75.6 
f)  80 80 80.3 80.6 
g)  82 82 82.3 82.6 
h)  90 90 90.3 90.6 
i)  100 100 100.3 100.6 
j)  110 110 110.3 110.6 
k)  125 125 125.3 125.6 
l)  140 140 140.3 140.7 
m)  160 160 160.3 160.7 
n)  180 180 180.3 180.7 
o)  200 200 200.3 200.8 
 
7.1.2 Wall thickness  
The wall thickness of the fitting shall be in accordance with  Table 2 . 
   
© KEBS 2022 – All rights reserved  v 
 Table 2  — Wall thickness of fitting body  
S/No.  Nominal size  Nominal inside 
diameter (mm) Minimum wall 
thickness  
(mm)  DN/ID  (mm) 
a)  32 32 1.8 
b)  40 40 1.8 
c)  50 50 1.8 
d)  63 63 1.8 
e)  75 75 1.9 
f)  80 80 1.9 
g)  82 82 1.9 
h)  90 90 2.2 
i)  100 100 2.2 
j)  110 110 2.7 
k)  125 125 3.1 
l)  140 140 3.1 
m)  160 160 4.0 
n)  180 180 4.0 
o)  200 200 4.9 
 
   
vi © KEBS 2022 – All rights reserved  
 7.1.3 Diameter and length of socket  
The dimensions of the diameter and length of the socket shall conform to Table 3  
Table 3 — Diameters and lengths of sockets (metric series) Dimensions in mm  
S/No.  Nominal size  Nominal inside 
diameter (mm) Minimum wall 
thickness  
 (mm) DN/ID (mm) 
a)  32 31.9 25 
b)  40 39.9 25 
c)  50 49.9 30 
d)  63 62.9 36 
e)  75 74.8 40 
f)  80 79.8 42 
g)  82 81.8 43 
h)  90 89.8 46 
i)  100 99.8 46 
j)  110 109.8 48 
k)  125 124.7 51 
l)  140 139.7 54 
m)  160 159.7 58 
n)  180 179.7 60 
o)  200 199.7  60 
 
8 Mechanical characteristics of fittings  
8.1 Flexibility or mechanical strength  
When the fitting is tested as per ISO 13264, there shall be no sign of splitting, cracking, separation and/or 
leakage.  
8.2 Fitting Impact/Strength (Drop test)  
8.2.1  Five fittings of each diameter and type applicable (homopolymer or copolymer) shall be conditioned for 
at least 30 min at a temperature of 23  °C ± 2  °C for homopolymers and 0  °C ±1  °C for copolymers. Within 10 s  
after the conditioning treatment, each fitting shall be dropped freely in various positions on to a flat concrete 
floor from the heights specified below:  
a) for D ≤ 75 mm, drop from (2  ± 0.1) m;  
b) for D > 75 mm, drop from (1  ± 0.1) m.  
8.2.2  If none of the specimens is damaged in the test, the fittings shall be accepted. If one fitting is damaged, 
the test shall be repeated with five further fittings. None of these last five fittings shall be damaged.  
NOTE   In the context of this test, “damage” means any vis ible split or any complete breakage in the body of the fitting. 
Surface scratches, scuffing, or chipping of edges which may occur in the test does not constitute damage.   
© KEBS 2022 – All rights reserved  vii 
 9 Physical characteristics of fittings  
9.1 Oven test of fittings  
9.1.1  When tested in  accordance with annex A, fittings shall not exhibit excessive blistering, delamination, 
cracking or weld line splitting. Near to normal injection points, the depth of penetration of cracks, etc., shall not 
exceed 50 % of the wall thickness at that point.  
9.1.2  When fittings are moulded by end gating techniques, the depth of penetration of cracks, etc., shall be 
not greater than 25 % of the corresponding socket depth.  
10 Performance requirements  
10.1 Watertightness  
Joints between pipes and fittings, pipes and pipes, and fittings and fittings shall not leak when tested in 
accordance with annex B.  
10.2 Airtightness  
Joints between pipes and fittings, pipes and pipes, and fittings and fittings shall remain airtight when tested in 
accordance with annex C.  
11  Marking  
11.1 General  
11.1.1 Marking elements shall be labelled or printed or formed directly on the pipe fitting (or any combination 
of these) or labelled or printed on the packaging.  
11.1.2 Marking on a pipe fitting shall not initiate cracks or other types of defects likely to prevent compliance 
with the requirements of this standard.  
10.2 Pipe fittings  
10.1 The minimum required marking of fittings shall include the following:  
a) number of this standard              KS……………  
b) manufacturer`s name and/or tr ademark  
c) nominal size for example  200  
d) nominal angle for example  45° 
e) material , (PP) and  
f) manufacturers information  
10.2 To ensure traceability, the following details shall be given:   
i) the production period (year and month), in figures or in code; and  
ii) name or code for the production site if the manufacturer is producing at different sites.  
 
  
viii © KEBS 2022 – All rights reserved  
 Annex  A 
(normative)  
 
Oven test for fittings  
A.1 Apparatus  
Oven , in which the fittings can be exposed to a temperature of 150°C ± 2°C.  
C.2 Test pieces  
Select three test pieces from each type of fitting.  
C.3 Test procedure  
See ISO 580  
  
© KEBS 2022 – All rights reserved  ix 
 Annex  B 
(normative)  
 
Watertightness test  
B.1 Apparatus  
B.1.1  Apparatus , to which the test assembly can be  connected, allowing a controlled water pressure to  be 
applied.  
B.1.2  Precision  pressure gauge.  
B.2 Test assembly  
Pipes, fittings and joints in accordance with this International Standard in all other respects shall be  used.  
The connection (joint) shaII be made in accordance with the manufacturer’s instruction.  
B.3 Procedure  
If the joint to be tested permits deflection, perform the test with the test assembly under the maximum possible 
deflection of the axis without forcing.  
Connect the test assembly (see clause B.2) to the precision pressure gauge ( B.1.2). By allowing water to enter  
the test assembly, gradually increase the internal pressure from 0 MPa to 0 .05 MPa (0 bar to 0 .5 bar) over a 
period of not greater than 15 min and maintain the pressure of 0 .05 MPa (0,5 bar) for at least 15 min.  
B.4 Test requirement  
The test requirement ( see 10.1) shall be fulfilled for all types of test assembly, including those combining 
minimum spigot ends and maximum sockets.   
x © KEBS 2022 – All rights reserved  
 Annex  C 
(normative)  
 
Elevated -temperature cycling test - 5-cycle test  
C.1 Apparatus  
C.1.1  Apparatus , to which the test assembly can be connected, allowing a controlled air pressure to be 
applied.  
C.1.2  Precision pressure gauge or manometer.  
C.2 Test assembly  
Pipes, fittings, and joints in accordance with this standard in all other respects shall be used.  The connection 
(joint) shall be made in accordance with the manufacturer’s instructions.  
The test assembly shall consist of a specimen of pipe mounted in two clamped blocks. Seal one end of the pipe 
with a plug that has a combined water and air inlet. Insert any fitting or joint  into the open end of the pipe. The 
joint or fitting shall then be sealed at all open ends with plugs, one of which has a water outlet and shut -off valve 
mounted centrally in the sealing plug.  
C.3 Procedure  
C.3.1  Apply a strong solution of soapy water or d etergent around the annular space between the mouth of 
the fitting and the pipe.  
C.3.2  Open the water outlet valve and close the air inlet valve on the pipe shut -off. 
C.3.3  Open the water inlet valve. When the assembly is half full, that is , when water flo ws from the outlet, 
close the water inlet and outlet valves.  
C.3.4  Open the air inlet valve and increase the internal air pressure to 0.01 MPa ± 0.001 MPa (0.1 bar ± 
0.01bar) at ambient temperature. Maintain this pressure for 5 min.  
C.3.5  Note, during this  5 min period, any leaks which occur between the mouth of the fitting and the pipe, and 
which are evident by the formation of bubbles.  
C.3.6  Deflect the pipe manually in the socket of the fitting until it reaches the maximum permissible deflection 
for the particular joint under test. Carry out this deflection at 0°, 90°, 180° and 270° maintaining it for 1 min in 
each of these directions.  
C.4 Test requirements  
No water leaks shall occur, but if bubbles appear at any time during the test, a new application of  soapy water 
or detergent shall be made. If there is still a continuous emission of bubbles during the test, the joint shall be 
deemed not to meet the requirements of the test.  
The test requirements (see 10.2) shall be fulfilled for all types of test asse mbly.   
© KEBS 2022 – All rights reserved  xi 
 Annex  D 
(normative)  
 
Elevated -temperature cycling test ― 5-cycle test  
D.1 Test assembly  
D.1.1  The test assembly shall consist of a vertical stack of pipes with fittings and two near -horizontal pipe 
assemblies with fittings . 
D.1.2  Installation shall be carried out on a firm wall or frame with guide and anchor brackets, with no other 
support of the test assembly.  
D.1.3  Anchor brackets shall be located directly below or behind the sockets of each pipe length. Guide 
brackets for near -horizontal assemblie s shall be positioned appropriately.  
D.1.4  It shall be checked that the test assembly exhibits no sagging greater than 0.1D at the mid -point 
between two guide brackets . 
D.1.5  Devices shall be provided and  positioned to measure any sagging f1 and f2 of the test assembly.  
D.1.6  Room for expansion of pipes shall be provided for all spigot ends of pipes, but not for the spigot ends 
of fittings. The entry of hot water into the test assembly shall be direct; there shall be no heat absorbing 
intermediate pieces.  
D.2 Procedure  
D.2.1  Test the assembly for watertightness and airtightness in accordance with D.3.1 and D.3.2.  
D.2.2  Subject the test assembly to the passage of hot and cold water according to the following schedule for 
5 cycles:  
a) circulation of water at 93° C ±2°C for 15 min, at a flow -rate of 0.3 I/s (18 l/min);  and 
b) circulation of water at 15°C ± 5°C for 10 min, at a flow -rate of 0.3 I/s (18 I/min.  
D.2.3  During the cycling test : 
a) check that the temperature of the water remains constant within the specified li mits; 
b) note any leaks from the test assembly and any “incidents” which may have an influence on the 
results ; and  
c) record the sagging f1 and f2 between guide brackets.  
D.2.4  After completion of the cycling test, carry out the water -tightness test again, as d escribed in D.3.1.  
D.3 Tightness test procedures  
D.3.1  Watertightness  
Carry out the following procedure:  
D.3.1.1  Seal off the lower end of the test assembly.   
xii © KEBS 2022 – All rights reserved  
 D.3.1.2   Apply a pressure of at least 0.01 MPa (0.1 bar) to each joint by filling the installation with water.  
D.3.1.3  Maintain the pressure for a period of 1 min.  
D.3.1.4  Take note of any leaks at each joint.  
D.3.2  Airtightness  
Carry out the following procedure:  
D.3.2.1  Seal off the ends of the test assembly.  
D.3.2.2  Coat the annular space between spigot and socket ends of joints with soapy water.  
D.3.2.3  Apply an air pressure of 0.01 MPa (0.1 bar) at ambient temperature.  
D.3.2.4  Maintain the pressure for a period  of 1 min.  
D.3.2.5  Take note of any leaks, evident through the formation of bubbles.  
D.4 Test requirements  
D.4.1 The joints shall remain watertight and airtight before and after the 5 -cycle test.  
D.4.2  The sagging at the mid -point between two guide bracket s shall not exceed 0.1D.  
 
 
  
© KEBS 2022 – All rights reserved  xiii 
 Annex  E 
(normative)  
 
Cycling tests ― General information for both 5 -cycle tests  
E.1 Test report  
The test report shall include the following information:  
a) statement indicating the cycling test carried out (i.e. 5 -cycle test);  
b) types and dimensions of the components used in the test assembly;  
c) all test parameters;  
d) results of leak -proofness tests before the cycling test;  
e) observations during the cycling test;  
f) any sagging noted;  
g) results of final inspection of the test assembly;  and 
h) all details not provided for in this Standard, as well as any incidents which might have had an 
influence on the results.  
E.2 Key to symbols  
The symbols used to specify or report on a test assembly shall comply with lSO/TR 7024