FINAL DRAFT UGANDA 
STANDARD  FDUS 855-1
First Edition
2009-mm-dd
 
Reference numbe  
r
FDUS 855-1: 2009
  
  © UNBS 2009 
  
Thermal solar systems and components – Factory made 
systems – Part 1: General requirements  
 FDUS 855-1: 2009 
ii © UNBS 2009 – All rights reserved
 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 
Kampala  
Uganda 
Tel: 256 41 4505995 
Fax: 256 41 4286 123 
E-mail: unbs@infocom.co.ug 
Web: www.unbs.go.ug FDUS 855-1: 2009 
© UNBS rved iii
  2009  – All rights reseContents Page 
Foreword ............................................................................................................................................................iv  
1 Scope ......................................................................................................................................................1  
2 Normative references ............................................................................................................................1  
3  Terms and definitions ..........................................................................................................................2  
3.1  Expansion line ......................................................................................................................................2  
3.2  Safety line ..............................................................................................................................................2  
3.3  Blow-off line ..........................................................................................................................................2  
3.4  Factory-made solar systems ...............................................................................................................2  
4  Requirements ........................................................................................................................................3  
4.1  General ..................................................................................................................................................3  
4.2  Materials ................................................................................................................................................5  
4.3  Components and pipework .................................................................................................................5  
4.4  Safety equipment ..................................................................................................................................6  
4.5  Resistance to external influences ......................................................................................................6  
4.6  Documentation .....................................................................................................................................7  
4.7  Labelling ................................................................................................................................................9  
4.8  System performance ..........................................................................................................................10  
Annex A (informative)  Conformity assessment ...........................................................................................11  
Bibliography ............................................................................................................................... .......................12  
 
 FDUS 855-1: 2009 
iv © UNBS 2009 – All rights reserved
 Foreword 
Uganda National Bureau of Standards (UNBS) is a parastatal under the Ministry  of Tourism, Trade and 
Industry established under Cap 323, of the Laws of Uganda.  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.  
Committee membership 
The following organisations were represented on Energy Management Subcommittee on Solar Energy, UNBS TC 13/SC 3, in the preparation of this standard: 
• Renewable Energy Department, Minist ry of Energy and Mineral Development 
• Makerere University 
• Incafex Solar Systems 
• Battery Masters (U) Limited 
• Equator-sun (U) Limited 
• Ultratec (U) Limited 
• Sonnerkraft Solar Systems 
• Solar Masters 
• Uganda National Plumbers Association 
• Uganda Institute of Professional Engineers 
• Uganda National Bureau of Standards FDUS 855-1: 2009 
© UNBS rved v
  2009  – All rights rese 
 UGANDA STANDARD DUS 855-1: 2009
 
UNBS All rights reserved  1
 2009 – Thermal solar systems and components – Factory made 
systems – Part 1: General requirements 
1 Scope 
This Uganda Standard specifies requirements on durab ility, reliability and safety for Factory Made thermal 
solar heating systems. The standard also includes provisions for evaluation of conformity to these 
requirements. 
The requirements in this standard apply to Factory Made solar systems as products The installation of these 
systems itself is not considered, but requirements are given for the documentation for the installer and the 
user which is delivered with the system (see also 4.6) 
2 Normative references 
The followings referenced documents are indispensable fo r the application of the Uganda Standard. For dated 
references, only the edition cited applies. For undated references, the latest edition of the referenced 
document (including any amendments) applies. 
EN 806-1, Specifications for installations inside buildings  conveying water for human consumption — Part 1: 
General 
 
ISO 6612, Windows and door height windows — Wind resistance tests 
 
ISO 15783, Seal-less rotodynamic pumps — Class II — Specification 
 
ISO 9906, Rotodynamic pumps — Hydraulic performance acceptance tests — Grades 1 and 2 
 
ISO 4126-1, Safety devices for protection against excess ive pressure — Part 1: Safety valves 
 
ISO 4126-2, Safety devices for protection against excessive pres sure — Part 2: Bursting disc safety devices 
 
ISO 4126-3, Safety devices for protection against excessive pressure — Part 3: Safety valves and bursting 
disc safety devices in combination 
 
ISO 4126-4, Safety devices for protection against excessive pressure — Part 4: Pilot-operated safety valves 
 
ISO 4126-5, Safety devices for protection against excessive pressure — Part 5: Controlled safety pressure 
relief systems (CSPRS) 
 
ISO 4126-6, Safety devices for protection against excessive pressure — Part 6: Application, selection and 
installation of bursting disc safety devices 
 
ISO 4126-7, Safety devices for protection against excessive pressure — Part 7: Common data 
 
ISO 4126-9, Safety devices for protection against excessive pres sure — Part 9: Application and installation of 
safety devices excluding stand-alone bursting disc safety devices 
 
ISO 9393-1, Thermoplastics valves for industrial applicatio ns — Pressure test methods and requirements — FDUS 855-1: 2009 
2 ©UNBS served
 2009  – All rights rePart 1: General 
 
ISO 9393-2, Thermoplastics valves for industrial applicat ions — Pressure test methods and requirements 
—Part 2: Test conditions and basic requirement 
 
DUS 854-1, Thermal solar systems and components — Solar collectors — Part 1: General requirements 
 
ISO 10721-1, Steel structures — Part 1: Materials and design 
 
ISO 10721-2, Steel structures — Part 2: Fabrication and erection 
 
ISO/TR 11069, Aluminum structures — Material and design — Ultimate limit state under static loading 
 
DUS 854-2, Thermal solar systems and components — Solar collectors — Part 2: Test methods 
 
DUS 855-2, Thermal solar systems and components — Factory made systems — Part 2: Test methods 
 
ISO 9488, Solar energy — Vocabulary 
 
ISO/TR 10217, Solar energy — Water heating systems — Guide to material selection with regard to 
 internal Corrosion 
3   Terms and definitions 
For the purposes of this Uganda Standard, the te rms and definitions given in ISO 9488 and the following 
apply. 
 3.1   
expansion line 
for systems with closed expansion vessels, the co nnecting line between the collectors and the pressure 
expansion vessel 
 
3.2  
safety line 
for systems with closed expansion vessels: the con necting line between the collector array and the safety 
valve 
For systems with open expansion vessels: the connecting line between the collector array and the open 
expansion vessel 
3.3  
blow-off line 
connecting line between the outlet of the safety valve and the environment 
 
3.4  
factory-made solar systems 
packaged solar energy system for the purpose of hot wate r preparation only, either of the close-coupled or 
remote store type. The system consists  of either one integral component or  of a uniform set and configuration 
of components. It is produced under conditions, whic h are presumed uniform, and offered for sale under the 
same trade name.  
 
NOTE 1 A single system can be tested as a whole in a test  laboratory, leading to representative results for all 
systems with the same trade name, conf iguration, components and dimensions. 
 
NOTE 2 External auxiliary water heating devices that are placed in series with the Factory Made system are 
not considered to be part of the system. Cold water piping from the cold water grid to the system as well as 
piping from the system to an external auxiliary heater or to tapping points is not considered to be part of the DUS
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integrated heat exchanger or piping for space heatin g option is not considered to be part of the system. 
 
4   Requirements 
4.1  General 
The system shall fulfil general safety requirements e.g. ca re shall be taken to avoid protruding sharp edges on 
the outside of the system. 
4.1.1 Suitability for drinking water 
The system shall confirm to EN 806-1 
4.1.2 Water contamination 
The system has to be designed to avoid water contaminat ion for backflow from all circuits to drinking main 
supplies. 
4.1.3 Freeze resistance 
4.1.3.1 General 
The manufacturer shall state a minimal allowed temperatur e for the system. The parts of the system that are 
exposed to the outdoors shall be able to withstand fr eezing to this specified temperature without any 
permanent damage. 
The manufacturer shall describe the method of freeze protection used for the system 
Any indoor components that are to be installed in places where temperatures can drop below 0 oC, shall be 
protected against freezing. 
The freezing mechanism shall be tested in accordance with 5.1 of DUS 855-2 
4.1.3.2 Freeze protection by means of antifreeze fluid 
The manufacturer shall define the composition of the heat transfer fluid, including additives, allowed for the 
system. 
Precautions shall be taken to prevent the antifreeze fluid from deterioration as a result of high temperature 
conditions. These precautions shall be checked in accordance with 5.2 of DUS 855-2  
NOTE In general the minimal allowed temperature of the system is equal to the freezing point of the 
antifreeze fluid.  If the concentration of some antifreeze fluids – like glycols – exceeds a certain limit, they can 
freeze without damaging the system. In this case the minimal allowed temperature can be lower than the freezing point of the antifreeze fluid. 
4.1.4 Over temperature protection 
4.1.4.1 General 
The system shall have been designed in such a away  that prolonged high solar irradiation without heat 
consumption does not cause any situation in which spec ial action by the user is required to bring the 
system back to normal operation. 
When the system has a provision to drain an amount of  drinking water as a protection against overheating, the 
hot water drain shall be constructed in such a away that no damage is done to  the system or any other FDUS 855-1: 2009 
4 ©UNBS served
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inhabitants from steam or hot water from the drain (see 4.6.2) 
When the overheating protection of the system is d ependent on electricity supply and/or cold water supply, 
this shall be stated clearly in the instruct ions and on the system (see 4.6.3 and 4.7) 
In case of drainback, system shall be checked in accordance with 5.1 of DUS 855-2 
4.1.4.2 Scald protection 
When the system is tested in accordance with 5.2 of DUS 855– 2, no steam sha ll escape from any tapping 
point. When this test has been performed with other than the highest irradiations this shall be mentioned in the 
documentation for the user (see 4.6.3) 
For systems in which the temperature of the domestic hot water delivered to the user can exceed 60 oC, the 
assembly instructions shall mention t hat an automatic cold water mixing devic e or any other device to limit the 
tapping temperature to at most 60 oC ± 5 oC shall be installed on the solar heating system or elsewhere in the 
domestic hot water installation (see also 4.6.2). 
This device shall be able to withstand the maximum pos sible domestic hot water temperature from the solar 
heating system.  
4.1.4.3 Over temperature protection for materials 
The system shall have been designed in such a way t hat the maximal allowed temperature of any material in 
the system is never exceeded. 
4.1.5 Reverse flow protection 
The system shall contain provisions in order to prevent increased heat loss resulting from reverse flow in any circuit. This shall be checked in accordance with 5.10 of DUS 855- 2 
4.1.6 Pressure resistance 
The storage tank and heat exchangers in this tank  shall withstand 1.5 times the manufacturer’s stated 
maximum individual working pressures. 
When tested in accordance with 5.3 of DUS 855-2 to the above pressures, there shall be no visible permanent 
damage or leakage of the system components and interconn ections. After the waiting period in the test, the 
hydraulic pressure shall not have dropped more than 10% from the value measured at the start of the waiting 
period. 
When non-metallic materials are used in any circuit, this circuit shall withstand the above – mentioned 
pressures for at least one hour when tested at hi gh temperature in accordance with DUS 854 -1 
The drinking water /water mains circuit shall withstan d the maximum pressure required by national drinking 
water regulations for open or closed drinking water installations. 
The system shall have been designed in such a way that t he maximal allowed pressure of any materials in the 
system is never exceeded. 
Every closed circuit in the system shall contain a safe ty valve. This safety valve shall withstand the highest 
temperature that can be reached at its location. It shall conform to ISO 4126 . If thermostatic valves are used, 
these shall conform to ISO 9393. 
4.1.7 Electrical safety 
If the system contains any electrical devices, t hese shall conform to IEC 60335-1 and IEC 60335- 2- 21.  DUS
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Any parts of the system to be mounted outdoors sha ll be resistant to UV radiation and other weather 
conditions over the prescribed maintenance interval. Wh en any maintenance or replacement of system parts 
is required in order to maintain the system’s working or der over a period of 10 years, this shall be clearly 
stated in the documents for the user. 
All materials used in the collector loop should confor m to ISO/TR 10217 in order to avoid any internal 
corrosion. 
4.3  Components and pipe work 
4.3.1 Collector 
For systems whose collector can be tested separately, the collector shall conform to DUS 854 -1, with the 
exception of: 
- internal pressure tests for absorber (see 5.3.2 of DUS 854-1); 
- freeze resistance test (see 5.3.10 of DUS 854-1); 
- thermal performance measurem ent (see5.3.9 of DUS 854-1). 
For systems whose collector cannot be tested separately (for instance int egrated collector-store systems), the 
whole system shall conform to this standard, with the exception of: 
- internal pressure tests for absorber (see 5.3.2 of DUS 854-1); 
- exposure test (see 5.3.4 of DUS  854-1), on the condition that the installation manual for the 
system specifies that the empt y system shall be protected against prolonged exposure to solar 
radiation; 
- internal thermal shock test (see 5.3.6 of DUS 854-1); 
- thermal performance measurem ent (see 5.3.9 of DUS 854-1); 
- freeze resistance test (see 5.3.10 of DUS 854-1). 
4.3.2 Supporting frame 
Manufacturer shall state the maximum possible loads fo r their supporting frame, in accordance with ISO 
10721 (steel) and ISO/TR 11069 (aluminium) 
This shall be mentioned in the documents for the installer. 
4.3.3 Piping 
The materials of the collector loop shall conform to ISO/TR 10217. 
The design and materials in the system shall be such t hat there is no possibility of deforming, clogging or lime 
deposit in its circuits that will drastically influence the system performance and safety. 
Circulation pumps in the system shall conform to ISO 9906 and ISO 15783. 
4.3.4 Heat Exchangers FDUS 855-1: 2009 
6 ©UNBS served
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exchangers in contact with water mains/drinking water shall be designed such that scaling is prevented or 
there shall be a facility for cleaning. 
NOTE High temperature difference between the metal surfac e of the heat exchanger and the surrounding drinking 
water mainly causes scaling. This can be avoi ded by increasing the heat exchanger area. 
4.3.5 Control system 
When present, the collector temperature sensor shall withstand stagnation conditions as specified in DUS 
854-2 without drifting by more than 1 K. 
When present, the store temperature sensor shall withstand 100 oC without altering by more than 1 K. 
The location and installation of all temperature sensors shall ensure a good thermal contact with the part of 
which the temperature shall be measured. The temperature sensors shall be insulated against ambient. 
4.4  Safety equipment 
4.4.1 Safety valves 
Each section of the collector array, which can be shut o ff, shall be fitted with at least one safety valve. ICS 
systems shall be fitted with at least one safety valve, which may be integrated with an inlet combination. The 
safety valve shall resist the temperature conditions whic h it is exposed to, especially the highest temperature 
that can occur. The safety valve s hall resist the heat transfer medium. The safety valve shall be dimensioned 
such that it can release the highest flow of hot water or steam that can occur. The dimension of the safety 
valve(s) shall be proved by suitable means. 
4.4.2 Safety lines and expansion lines 
If the system is equipped with safety line, this safe ty line shall not be capable of being shut off. 
If the system is equipped with a safety line and an ex pansion line, the safety line and expansion line shall be 
dimensioned such, that for highest flow of hot water or steam that can occur, at no place in the collector loop 
the maximum allowed pressure is exceeded due to the pressure drop in these lines. The dimension of the safety line and expansion line sha ll be proved by suitable means. 
The expansion line and safety line shall be connected and la id in such a way that any accumulations of dirt, 
scale or similar impurities are avoided. 
4.4.3 Blow-off lines 
If the system is equipped with blow-off lines, these blow-off lines shall be laid in such away that they cannot 
freeze up and that no water can accumulate within t hese lines. The orifices of the blow-off lines shall be 
arranged in such a way that any steam or heat transfer medium issuing from the safety valves does not cause 
any risk for people, materials or environment. 
4.5  Resistance to external influences 
The components, which are exposed to the effect of weather, shall resist weathering and shall be designed, 
constructed and fastened in such a way that they can withstand the weather. 
In respect of lightening protection, t he system should conform to IEC 61024-1. 
NOTE In Annex E & F of DUS 855-2,  a test method based on IEC 61024 -1 is given for solar water heating 
systems. 
 DUS
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4.6.1 General 
With each Factory Made solar heating system, the manufacturer or official supplier shall deliver documents for 
assembly and installation (for the installer) and documents for operation (for the user). These documents shall 
be written in the official language(s) of the country of  sale. These documents shall include all instructions 
necessary for assembly and operation, including maint enance, and draw attention to further requirements and 
technical rules that are concerned. 
4.6.2 Documents for the installer 
The assembly instructions shall be appropriate to  the system and include information concerning: 
a)  Technical data, at least those with respect to: 
1) layout of the system; 
2) location and nominal diameters of all external connections; 
3) an overview with all components to be delivered (such as solar collector, storage tank, 
support structure, hydraulic circuit, back-up provisions, control system and accessories), with 
information on each component: type, electrical power, dimensions, weight, marks and mounting; 
4) maximum operating pressure of all fluid circuits  in the system, such as the collector circuit, 
the domestic hot water line and the aux iliary heating circuit (in Pa); 
5) working limits; admissible temperatures , pressures etc throughout the system; 
6) type of corrosion protection; 
7) type of heat transfer fluid; 
b) Packing and transport of the whole system and /or components and way of storage ( outdoors, 
indoors, packed, not packed); 
c) Installation guidelines with recommendations concerning: 
1) mounting surfaces; 
2) distances to walls and safety with regard to frost; 
3) the way the entrance of piping into the building shall be finished (resistance against rain and 
moisture); 
4) the procedure to be followed for thermal insulation of pipes; 
5) the roof integration of the collector (if appropriate); 
6) for drain-back or drain-down systems, the minimal pipe slope and any other instructions 
necessary to ensure proper draining of the collector circuit; 
d) If a support frame that is normally mounted outdoors is part of the system, the maximum value of V m 
(mean wind velocity) according to ISO 6612 and the statement that the system may only be installed 
in locations with lower values of V m; 
e) Method for pipe work connections; FDUS 855-1: 2009 
8 ©UNBS served
 2009  – All rights ref) Types and sizes of the safety and security devices and their draining . The assembly instruction shall 
demand that  any pressure relief valves from which steam can escape during normal or stagnation 
conditions shall be mounted, in such a way that no  injuries, harm or damage can be caused by the 
escape of steam. When the system has a provisio n to drain an amount of drinking water as a 
protection against overheating, the hot water drain shall be constructed in such a way that no 
damage is done to the system or any other materials in the building by the drained hot water; 
g) The necessary control and safety devices incl uding the wiring diagram, including the need for a 
thermostatic mixing valve which limits the draw-off temperature to 60 oC, when this is required 
according to 4.1.2.2; 
h) Reviewing, filling and starting up of the systems; 
i) Commissioning of the system; 
j) A checklist for the installer to che ck proper functioning of the system; 
k) The lowest temperature at which the system can withstand freezing; 
l) The required solar irradiation on the plane of the collector or the minimum solar lamp irradiance at 
the plane of the collector for wh ich overheating protection of the system has been tested according to 
5.2 of DUS 855-2, and the requirement  that the system shall not be us ed in climate zones with higher 
irradiation valves than these values. 
4.6.3 Documents for the user 
The operation instructions shall include information concerning: 
a) Existing safety and security components and their thermostat adjus tment where applicable; 
b) Implementation of the system drawing pa rticular attention to the facts that ; 
1) prior to putting the system in operation it sha ll be checked that all valves are properly working 
and the system is filled with water and/or antif reeze fluid completely or according to the 
manufacturer’s instructions; 
2) in the event of any failure condition a specialist shall be called in; 
c) Regular operation of safety valves; 
d) Precautions with regard to the risk of frost damage and/or overheating; 
e) The manner of avoiding failure when star ting under frost or possible frost conditions; 
f) Decommissioning of the system; 
g) Maintenance of the syst em by a specialist, including frequency of inspections and maintenance and a 
list of parts that need to be replaced during normal maintenance; 
h) Performance data for the system (see also 4.8): 
1) the recommended load range for the system  (in l/day) at specified temperature; 
2) the thermal performance and solar fraction of the system according to 5.9 of DUS 855-2, for 
loads in the specified recommended load range; 
3) the annual electricity consumption for pumps, control systems and electrical valves of the 
system for the same conditions as specified for the thermal performance, assuming a yearly 
pump operating time of the collector pump of 2000 h; DUS
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electrical power of these devices (in W) and their characteristics (e.g. switch-on 
temperatures); 
5) for a “solar-plus-supplementary system”, the maximum daily hot water load which can be met 
by the system without any contribution from solar energy, according to 5.10 of DUS 855-2 ; 
i) The require solar irradiation on the plane of the co llector or the minimum solar lamp irradiance at the 
plane of the collector for which overheating protection of the system has been tested according to 5.2 
of DUS 855-2 and the requirement that the system shall not be used in climate zones with higher 
irradiation values than these values; 
j) When the overheating protection of the system is dependent on elec tricity and/or cold water supply 
and/or the system being filled with drinking water, th e requirement to never switch off the electricity 
supply and/or the mains water supply, or that t he system is not drained when there is high solar 
irradiation; 
k) The fact that drinking water may be drained from the system during high irradiation situations, if this 
method is used to prevent overheating; 
l) The lowest temperature at whic h the system can withstand freezing; 
m) Type of heat transfer fluid; 
n) In case of solar heating systems with emergency  auxiliary heaters, instruct ions shall be issued that 
this emergency heater shall only be used for emergency heater purposes. 
4.7  Labelling 
Every system shall have the following information dur ably marked on the plate or label to be visible at 
installation: 
a) Name of manufacturer or re sponsible supplier of the system; 
b) System type indication; 
c) Manufacturing number or serial number; 
d) Year of manufacture – this may be included in the production or serial number in coded or clear form; 
e) Absorber and aperture area of the collector in m2; 
f) Nominal capacity of the storage vessel in L; 
g) Design pressure of the drinking water line in kPa; 
h) Collector heat transfer medium to be used; 
i) Permissible operating pressure of the collector he at transfer medium in kPa or, in case the system 
has an open or vented collector circ uit, a statement to this effect; 
j) When the overheating protection f the system is  depended on electricity or cold water supply and/or 
the system being filled with drinking water, a warnin g to this effect shall be marked on the system. In 
case of dependency on the electricity supply, the mains plug of the system shall also be clearly 
marked to this effect; 
k) Electrical power of all electric components. FDUS 855-1: 2009 
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The thermal performance of the system shall be tested ac cording to one of the two test methods specified in 
5.8 of DUS 855-2. The performance shall be reported to t he user in the format as sp ecified in Annex A of DUS 
855-2 (see also 4.6.3). 
 
 DUS
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(informative)  
 
Conformity assessment 
In Table A.1, guidelines are given to assess whether one or more tests should be repeated in order 
to assure that the changed product is still in conformity with the requirements. 
Table A.1 – Guidelines for repetition of tests in case that, components have been changed 
Component test Anti-
freeze 
fluid Control 
unit Collector   
a Store    
a Heat 
exchanger Supporting 
frame Collector 
piping or 
installation 
Freeze resistance x xbxcxd  xc
Over temperature  xbx x   x 
Pressure resistance   x x x  x 
Collector   x     
Lightning protection   x xd  xe
Mechanical 
strength      x   
Thermal 
performance fxgx x x x  xh
Ability to cover load xgx x x x  xh
a For ICS systems, a change on the ICS system im plies a change on both collector and the store 
b  If the control unit is involved in frost or overheating protection 
c Mainly for drain-back systems. 
d If the tank is placed outdoors. 
e If the material is changed (especially non-metal to metal) 
f When, in the judgement of the second/third party,  changes have a minor character or will improve the 
performance of the system, retesting of the pe rformance and the ability to co ver the load is generally not 
necessary and the old results can be used. 
g Usually not affected, except when the viscosity of the fluid changes 
h Mainly for thermosiphon systems 
 FDUS 855-1: 2009 
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[1] EN 1717, Protection against pollution of potable water in water installations and general requirements 
of devices to prevent pollution by backflow  
[2] IEC 61024-1, Protection of structures against fire, explosion and life hazards  
[3] IEC 60335-1, Household and similar electrical appliances – Safety – Part 1: General requirements  
[4} IEC 60335-2-21, Household and similar electrical appliances – Safety – Part 2-21: Particular 
requirements for storage water heaters  
  
UNBS All rights reserved  
 Certification marking 
Products that conform to Uganda standards may be  marked with Uganda National Bureau of Standards 
(UNBS) Certification Mark shown in the figure below.  
The use of the UNBS Certification Mark is gove rned by the Standards Act, and the Regulations made 
thereunder. This mark can be used only by those licens ed under the certification mark scheme operated by 
the Uganda National Bureau of Standards and in co njunction with the relevant Uganda Standard. The 
presence of this mark on a product or in relation to a product is an assurance that the goods comply with the 
requirements of that standard under a system of supervision, control and  testing in accordance with the 
certification mark scheme of the Uganda National  Bureau of Standards. UNBS marked products are 
continually checked by UNBS for conformity to that standard.  
Further particulars of the terms and conditions of  licensing may be obtained from the Director, Uganda 
National Bureau of Standards.  
 
 
2009 – DUS 
 
ICS 855-1: 2009 
27.160  
Price based on es 
UNBS All rights reserved  
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2009 –