FINAL DRAFT UGANDA 
STANDARD  
  FDUS ISO 9808
First Edition
2009-mm-dd
 
Reference numbe r
FDUS ISO 9808:1990
 © UNBS 2009
  
Solar water heaters — Elastomeric materials for absorbers, 
connecting pipes and fittings — Method of assessment 
 FDUS ISO 9808:1990 
 
© UNBS  2009 – All rights reserved ii Compliance with this standard does not, of itself confer immunity from legal obligations 
A Uganda Standard does not purport to include all necessary provisions of a contract. Users are 
responsible for its correct application  
© UNBS 2009 
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilised in any 
form or by any means, electronic or mechanical, in cluding photocopying and microfilm, without prior written 
permission from UNBS. 
Requests for permission to reproduce this document should be addressed to 
The Executive Director 
Uganda National Bureau of Standards 
P.O. Box 6329 
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Uganda 
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Fax: 256 41 286 123 
E-mail: unbs@infocom.co.ug
Web: www.unbs.go.ug  
 FDUS ISO 9808:1990  
© UNBS  2009 - All rights rese rved                iii National foreword 
Uganda National Bureau of Standards (UNBS) is a parastatal under the Ministry  of Tourism, Trade and 
Industry established under Cap 327, of the Laws of U ganda. UNBS is mandated to co-ordinate the elaboration 
of standards and is  
(a) a member of International Organisation for Standardisation (ISO) and  
(b) a contact point for the WHO/FAO Codex A limentarius Commission on Food Standards, and  
(c) the National Enquiry Point on TBT/SPS Agr eements of the World Trade Organisation (WTO). 
The work of preparing Uganda Standards is carried out through Technical Committees. A Technical 
Committee is established to deliberate on standards in a gi ven field or area and consists of representatives of 
consumers, traders, academician s, manufacturers, governme nt and other stakeholders. 
Draft Uganda Standards adopted by the Technical Committ ee are widely circulated to stakeholders and the 
general public for comments. The committee reviews the comments before recommending the draft standards 
for approval and declaration as Uganda Standards by the National Standards Council. 
This Final Draft Uganda Standard, FDUS ISO 9808, Solar water heaters — Elastomeric materials for 
absorbers, connecting pipes and fittings — Method of assessment,  is identical with and has been reproduced 
from an International Standard, ISO 9808:1990, Solar water heaters — Elastomeric materials for absorbers, 
connecting pipes and fittings — Method of assessment, and is being proposed for adoption as a Uganda 
Standard.  
This standard was developed by the Energy Management Standards Technical Committee (UNBS/TC 13). 
Wherever the words, "International Standard" a ppear, they should be replaced by "Uganda Standard." 
 INTERNATIONAL 
STANDARD ISO 
98Q8 
First edition 
1990-09-15 
~-~ _-__- ------ ---Y-P 
Solar water heaters - Elastomeric materials for 
absorbers, connecting pipes and fittings - 
Method of assessment 
Chauffe-eau solaires - Mafkriaux en klastom&-es pour absorbeur-s, 
raccords et tuyaux - Methode d’evalua tion 
~--- -- 
Reference number 
ISO 9808: 199O(E) ISO 9808:1990(E) 
Foreword 
ISO (the International Organization for Standardization) is a worldwide 
federation of national Standards bodies (ISO member bodies). The work 
of preparing International Standards is normally carried out through ISO 
technical committees. Esch member body interested in a subject for 
which a technical committee has been established has the right to be 
represented on that committee. International organizations, govern- 
mental and non-governmental, in liaison with ISO, also take part in the 
work. ISO collaborates closely with the International Electrotechnical 
Commission (IEC) on all matters of electrotechnical standardization. 
Draft International Standards adopted by the technical committees are 
circulated to the member bodies for voting. Publication as an Interna- 
tional Standard requires approval by at least 75 % of the member bodies 
casting a vote. 
International Standard ISO 9808 was prepared by Technical Committee 
ISO/TC 180, Solar energy. 
0 ISO 1990 
All rights reserved. No part of this publication may be reproduced or utilized in any form 
or by any means, electronie or mechanical, including photocopying and microfilm, without 
Permission in writing from the publisher. 
International Organization for Standardization 
Case Postale 56 + CH-1211 Geneve 20 l Switzerland 
Printed in Switzerland 
ii INTERNATIONAL STANDARD ISO 98083 990(E) 
Solar water heaters - Elastomeric materials for absorbers, 
connecting pipes and fittings - Method of assessment 
1 Scope 
This International Standard specifies a means of 
assessing elastomeric materials for use in the 
manufacture of absorbers, connecting piping and 
frttings for use in solar water heaters. 
2 Normative references 
The following Standards contain provisions which, 
through reference in this text, constitute provisions 
of this International Standard. At the time of publi- 
cation, the editions indicated were valid. All stan- 
dards are subject to revision, and Parties to 
agreements based on this International Standard 
are encouraged to investigate the possibility of ap- 
plying the most recent editions of the Standards in- 
dicated below. Members of IEC and ISO maintain 
registers of currently valid International Standards. 
ISO 34-1:- ‘), Rubber, vulcanized - Determination of 
tear strength - Part 1: Trouser, anqle and crescent c 
test pieces. 
ISO 37:1977, Rubber, vulcanized - Determination of 
tensile stress-strain properties. 
ISO 48:1979, Vulcanized rubbers - Determination of 
hardness (Hardness between 30 and 85 IRHD). 
ISO 188:1982, Rubber, vulcanized - Accelerated 
ageing or heat-resistance tests. 
ISO 471:1983, Rubber - Standard temperatures, hu- 
midities and times for fhe conditioning and testing 
of test pieces. 
ISO 1402:1984, Rubber and plastics hoses and hose 
assemblies - Hydrostatic testing. ISO 1431~1:1989, Rubber, vulcanized or thermoplas- 
tic - Resistance to ozone cracking - Part 1: Sfatic 
strain fest. 
ISO 165311975, Vulcanized rubbers - Determination 
of compression set under constant def7ection at low 
temperatures. 
ISO 1817:1985, Rubber, vulcanized - Determination 
of the effect of liquids. 
ISO 4661-1:1986, Rubber, vulcanized - Preparation 
of samples and test pieces - Part 1: Physical tests. 
ISO 7326:1984, Rubber and plastics hoses - Assess- 
ment of ozone resistance under static conditions. 
3 Test pieces 
The test pieces shall be as specified in the relevant 
test method. 
The test pieces required for the tests specified in 4.3 
and 4.7 should preferably be tut from samples of the 
finished product. Where this is not practicable test 
pieces may be tut from sheet material. 
If it is required to separate a section of fluid passage 
from a finished absorber, the test piece shall be 
prepared in accordance with ISO 4661-1. 
4 Qualification tests 
4.1 Hardness 
Hardness shall preferably be tested using the 
normal test set out in ISO 48. 
The test may also be performed using the micro-test 
set out in ISO 48, on a test piece of thickness not 
less than 2 mm, but it should be noted that the two 
methods may give a different result on a particular 
1) To be published. ISO 9808:1990(E) 
test piece. In case of doubt, the results of the normal 
test shall be considered as definitive. 
4.2 Compression set at low temperature Upon being removed from the oven, the test pieces 
shall be conditioned for 24 h in a Standard atmos- 
phere at 23 “C and 50 % humidity, in accordance 
with ISO 471. 
Compression set shall be tested in accordance with 
ISO 1653, using a small-type test piece maintained 
under a compression of 25 % for 24 h at a temper- 
ature of -40 “C. Table 1 - Test temperatr re for ageing tests 
Maximum Service 
temperature 
“C 
4.3 Resistance to ozone 
Resistance to ozone shall be tested in accordance 
with ISO 1431-1, procedure A, for test pieces other 
than hose or absorber fluid passages. 
The test period shall be 7 days, and the ozone con- 
centration shall be 200 pphm & 20 pphm. The tem- 
perature of test shall be 40 OC + 2 “C and the 
elongation of the test piece shall be-20 Oh. 
For hose or absorber fluid passages, the test shall 
be carried out in accordance with ISO 7326. 100 70 
125 100 
150 125 
175 150 
200 175 
225 200 
250 225 
1) Type (heat resistance) classification in accordance with 
ISO 4632-1 :1982, Rubber, vukanized -- Classification --- 
Part 1: Description of the classification System. 
2) The test temperatures are one step higher than the 
maximum Service temperature to which the material may be 
subjected. 
4.4 Tear strength 
Tear strength shall be tested in accordance with 
ISO 34-1, method C, using a crescent test piece. 5.2 Properties after ageing 
The following properties of the material shall be de- 
termined upon completion of the artificial ageing: 
4.5 Tensile strength 
a) hardness, in accordance with 4.1; 
Tensile strength shall be tested in accordance with 
ISO 37, using a type 2 dumb-bell test piece. b) resistance to ozone, in accordance with 4.3; 
4.6 Elongation at break c) tensile strength, in accordance with 4.5; 
Elongation at break shall be tested in accordance 
with ISO 37, using a type 2 dumb-bell test piece. d) elongation at break, in accordance with 4.6; 
e) burst pressure, in accordance with 4.7. 
4.7 Burst pressure 
Burst pressure of hose or absorber fluid passages 
shall be tested in accordance with the relevant re- 
quirements of ISO 1402. The test piece shall be at 
least 450 mm long for items of internal diameter 
76 mm or smaller, and at least 600 mm long for 
larger items. 6 Immersion in heat-exchange fluids 
6.1 Immersion in propylene glycol 
NOTE 1 Burst pressure tests carried out at ambient 
temperature cannot be taken as indicative of the burst 
pressure at elevated temperatures. If the material is to be used in conjunction with 
propylene glycol, the test pieces required for the 
tests specified in 6.3 shall be immersed in propylene 
glycol at the appropriate test temperature given in 
table 1 for a period of 7 days in accordance with 
ISO 1817:1985, clause 11. 
5 Ageing tests 
5.1 Artificial ageing 6.2 Immersion in other heat-exchange fluids 
The test pieces required for the tests specified in 5.2 
shall be subjected to an ageing test in an air-oven 
in accordance with ISO 188, for a period of 14 days 
at a test temperature related to the maximum ser- 
vice temperature as listed in table 1. If the material is to be used in conjunction with a 
heat-exchange fluid other than propylene glycol, the 
immersion shall be performed using the heat- 
exchange fluid proposed. The test pieces required 
for the tests specified in 6.3 shall be immersed in the 
heat-exchange fluid at the appropriate test temper- 
2 ISO 9808:1990(E) 
ature given in table 1 for a period of 7 days in ac- 
cordante with ISO 1817:1985, clause 11. 
6.3 Properties after immersion 
The following properties of the material shall be de- 
termined upon completion of the immersion speci- 
fied in 6.1 or, if appropriate, 6.2: 
a) hardness, in accordance with 4.1; b) tensile strength, in accordance with 4.5; 
c) elongation at break, in accordance with 4.6; 
d) burst pressure, in accordance with 4.7. 
7 Test report 
The results of the tests described in clauses 4, 5 
and 6 shall be presented as shown in table2. 
Table 2 - Test report 
Resul tsl) 
Property of material 
Hardness [IRHO*)] Qualification test After ageing 
(clause 4) (clause 5) After immersion in 
propylene glycol (clause 6) After immersion in other 
fluid (to be specified) 
(clause 6) 
Tensile strength (M Pa) 
Elongation at break (%) 
Burst pressure of hose 
Wa) 
Compression set at low tem- 
perature (%) 
Resistance to ozone (condi- 
tion of test piece and any 
cracking) NR NR NR 
NR NR 
Tear strength - crescent 
test piece (kN/m) NR NR NR 
1) NR, not required. 
2) IRHD, International Rubber Hardness Degrees. 
3 This page intentionally left blank This page intentionally left blank ISO 9808:1990(E) 
UDC 697.7:678.074:[621.643.06+.2]:620.1 
Descriptors: solar energy, solar heating, solar water heaters, rubber products, tests, Performance tests, artificial ageing tests.