ICS 9 7.100.99 
 
Reference number  
DRS 212: 2022 
© RSB 202 2 
  
 RWANDA 
STANDARD  DRS 
212 
 
Second  edition  
2022-mm-dd 
 
 
Domestic storage solar water heating 
systems  — Requirements   
   
DRS 212: 2022 
©RSB 2022 - All rights reserved                 ii 
 In order to match with technological development and to keep continuous progress in industries, 
standards are subject to periodic review. Users shall ascertain that they are in possession of the latest 
edition 
 
 
 
 
 
 
 
 
© RSB 2022 
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized 
in any form or by any means, electronic or mechanical, including photocopying and microfilm, without 
prior written permission from R SB. 
Requests for permission to reproduce this document should be addressed to : 
Rwanda Standards  Board  
P.O Box 7099 Kigali -Rwanda  
KK 15 Rd, 49  
Tel. +250 788303492  
Toll Free: 3250  
E-mail: info@rsb.gov.r w 
Website: www.rsb.gov.rw  
ePortal: www.portal.rsb.gov.rw   DRS 212: 2022 
iii                ©RSB 202 2 - All rights reserved  
 Contents  Page 
Foreword  ................................ ................................ ................................ ................................ ...................  iv 
1 Scope  ................................ ................................ ................................ ................................ .............  1 
2 Normative references  ................................ ................................ ................................ ...................  1 
3 Terms and definitions  ................................ ................................ ................................ ..................  1 
4 Requirements  ................................ ................................ ................................ ................................  4 
4.1 Types  ................................ ................................ ................................ ................................ .............  4 
4.2 Hot water storage tank  ................................ ................................ ................................ .................  4 
4.3 Collector  ................................ ................................ ................................ ................................ ........  5 
4.3.1  Collector cover  ................................ ................................ ................................ .............................  5 
4.3.2  Hail c over  ................................ ................................ ................................ ................................ ...... 5 
4.3.3  Thermal insulation  ................................ ................................ ................................ ........................  5 
4.3.4  Stagnation requirements  ................................ ................................ ................................ .............  5 
4.3.5  Resistance to freezing  ................................ ................................ ................................ .................  6 
Annex  A (normative)  Installation, replacement and retrofit  ................................ ...............................  12 
Annex  B (normative)  Factor governing corrosion and internal scaling of sola r water heating 
systems  ................................ ................................ ................................ ................................ ....... 13 
 DRS 212: 2022 
©RSB 2022 - All rights reserved                 iv 
 Foreword   
Rwanda Standard s are prepared  by Technical Committees and approved by Rwanda Standards Board (RSB) 
Board  of Directors in  accordance with the procedures of RSB, in compliance with Annex 3 of the WTO/TBT 
agreement on the preparation, adoption and application of standards.  
The main task of technical committees is to prepare national standards.  Final Draft Rwanda S tandards adopted 
by Technical committ ees are ratified  by me mbers of RSB Board of Director s for publication and gazettment as 
Rwanda Standards.  
DRS 212 was prepared by Technical Committee RSB/TC 049, Solar energy  systems and accessories . 
In the preparation of this standard, reference was made to the following standard s: 
1) SANS 1307: 2012 , Domestic storage solar water heating systems  
2) RS ISO 9459 -1: 1993, Solar heating — Domestic water heating systems — Part 1: Performance rating 
procedure using indo or test methods  
3) RS ISO 9459 -2: 1995 , Solar heating — Domestic water heating systems — Part 2: Outdoor test 
methods for system performance characterization and yearly performance prediction of solar -only 
systems  
4) ISO 9459 -4: 2013 , Solar heating — Domestic water heating systems — Part 4: System performance 
characterization by means of compone nt tests and computer simulation  
5) ISO 9459 -5: 2007 , Solar heating — Domestic water heating systems — Part 5: System performance 
characterization by means of whole -system tests and computer simulation  
The assistance derived from the above source is hereby ac knowledged with thanks.   
Committee membership  
The following organizations were represented on the Technical Committee s on Solar energy  systems  and 
accessories  (RSB/TC 049) in the preparation of this standard.  
LE-GTSIM Ltd  
Ministry of Infrastructure  
Rwanda Energy Group/Energy Development Corporation Limited (EDCL)  
Rwanda Military Hospital (RMH)  
TEECCSM Ltd   
University of Rwanda  - College of Science and Technology (UR -CST)  
Rwanda Standards Board (R SB) - Secretariat  DRS 212: 2022 
1                ©RSB 202 2 - All rights reserved  
 Domestic storage solar water heating systems — Requirements  
1 Scope   
This Draft  Rwanda Standard specifies the requirements for integral, close -coupled and split domestic storage 
solar water heating systems and includes specific requirements for solar collectors for solar water heating 
systems.  
It is not applicable to solar water heating systems for swimming pools or to industrial and commercial solar water 
heating systems, or instantaneous type domestic solar water heating systems.  
2  Normative references   
The following 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.  
RS EAS 12 , Potable water — Specification  
RS 116 -1, Electrical wir ing of premises — Part 1: Low -voltage installations  
DRS 213 , Domestic storage solar water heat ing systems  — Test method s 
DRS 214 , Domestic storage solar water heating systems — Requirements for installation, maintenance, repair 
and replacement  
RS IEC 60335 -2-21, Household and similar electrical appliances  — Safety — Part 2 -21: Particular requirements 
for storage water heaters  
RS ISO 9459 -2, Solar heating — Domestic water heating systems — Part 2: Outdoor test methods for system 
performance characteriza tion and yearly performance prediction of solar -only systems  
RS ISO 9806 , Solar energy — Solar thermal collectors — Test methods  
3 Terms and definitions   
For the purposes of this standard, the following terms and definitions apply.  
3.1 
absorber  
part of a sol ar heating collector that receives radiant energy and transforms it into thermal energy, which is used 
to heat the heat -transfer fluid passing through the collector or to heat the water directly   
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3.2 
acceptable  
acceptable to the authority administering thi s standard, or to the parties concluding the purchase contract, as 
relevant  
3.3 
aperture  
area in a collector cover through which unconcentrated solar radiant energy is admitted to the absorber  
3.4 
close -coupled system  
system, in which hot water is stored in a separate but close -coupled water storage tank, where the mechanical 
coupling between the collector and the tank are pre -manufactured and controls the position of the collector in 
relation to the tank  
3.5 
collector  
device that contains or incorp orates an absorber and a means for transferring thermal energy from the absorber 
to a fluid passing through the device  
3.6 
collector cover  
transparent or translucent material that covers the aperture and provides thermal retention and environmental 
protect ion of the unit  
3.7 
daily heat output  
energy output above mean inlet temperature of a collector (Ta − Tc = 10 °C) as determined by the thermal 
performance test, and normalized to a base of 20 MJ/ m2/d of solar energy input  
3.8 
direct heating system  
heating  system in which the potable water to be heated is circulated through the absorber, and the solar heat 
gathered by the collector is transferred directly to the potable water itself  DRS 212: 2022 
3                ©RSB 202 2 - All rights reserved  
 3.9 
hail cover  
cover for collector other than glazing that prevent s hail impact damage  
3.10 
heat exchanger  
device specifically designed to transfer heat between two physically separated fluids  
3.11 
heat transfer fluid  
medium, such as air, water or other fluid, that passes through a collector and carries absorbed thermal energy 
from the collector to the potable water to be heated  
3.12 
indirect heating system  
system in which an absorber transfers heat via a heat exchanger to the potable water to be heated  
3.13 
integral system  
system in which the hot water storage ta nk is incorporated integrally with the collector and water is stored in the 
body of the collector -storage tank unit  
3.14 
pumped circulation  
system in which water is circulated between the collector and storage tank by means of a mechanical circulation 
device 
3.15 
separate storage system  
split system in which the hot water storage container is remote from the collector(s)  
3.16 
solar water heating system  
complete operating system that uses radiant energy from the sun to produce hot water and comprises one or 
more collectors, one or more hot water storage tanks whether supported by supplementary energy sources or 
not, and all necessary interconnecting pipes and functional components   
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 3.17 
supplementary energy sources  
auxiliary heating source independent of solar  thermal radiation  
3.18 
thermosiphon circulation  
system in which water is circulated between the collector and storage tank by means of density changes of the 
heat transfer fluid  
4 Requirements  
4.1 Types  
A solar water heating system shall be one of the types giv en in Table 1:  
Table 1 — Solar water heating systems  
1 2 3 4 5 6 7 8 9 
Collector/Storage combinations  
integral  close -coupled/  combined collectors   Split/ evacuated tubes  
Heat transfer method  
Direct  Direct  Indirect  Direct  Indirect  
Circulation method  
thermo -
siphon  thermo -
siphon  Pumped1 thermo -
siphon  Pumped1 thermo -
siphon  Pumped1 thermo -
siphon  Pumped1 
1Pumped (forced) circulation shall be achieved with electrical mains and/or photovoltaic powered pumps . 
 
4.2 Hot water storage tank  
4.2.1  A hot water storage tank, with supplementary heating or with provision for supplementary heating (or 
with an integral heat pump) shall comply with RS IEC 60335 -2-21. 
4.2.3  Electrical components of a hot water storage tank that is intended to be insta lled on the outside of a 
building shall be at least IPX4, and effectively protected, by means of a corrosion resistant outer casing, against 
the effects of rain, wind and other elements. Other water heaters shall be at least IPX1.  
4.2.4  Seams on the outer casing and the entry holes for pipe connections shall be effectively sealed to make 
a permanent watertight closure. All exposed piping or fittings (or both) which form part of the storage tank, shall 
be of a non -corrosive material or protected against corr osion.  DRS 212: 2022 
5                ©RSB 202 2 - All rights reserved  
 4.3 Collector  
4.3.1  Collector cover  
 
4.3.1.1  If constructed in solid sheet form, the collector cover shall be secured so as to resist an upward and 
downward force of 200 N/m2. 
4.3.1.2  The collector cover of a solar water heating system shall be of such quality and strength that, when it is 
tested in accordance with RS 213 and/or RS ISO 9806, it does not suffer any damage that could impair its 
normal operation unless fitted with a hail cover.  
4.3.1.3  The collector cover shall have a high transmission  of visible and near infra -red radiation of wavelength 
up to 2.4 μm in order to maximize the input of solar radiation.  
4.3.1.4  The collector cover shall have a low transmission of infra -red radiation of wavelength exceeding 3 μm 
in order to minimize heat losses.  
4.3.2  Hail cover  
The hail cover of a solar water heater shall be of such quality and strength that, when it is tested in  accordance 
with RS 213, the collector and hail cover does not suffer any damage that could impair its normal operation.  A 
hail cover shall be corrosion resistant and easily removable for cleaning.  
4.3.3  Thermal insulation  
4.3.3.1  When tested in accordance  with RS 213, t hermal insulating material  used in construction of collector 
shall:  
a) not cause corrosion of the metal;  
b) not react in the presence of heat in a manner that  produce s corrosive salts or vapours; and  
c) be dimensionally stable under dry conditions at  the maximum expected temperatures likely to be reached 
in the collector.  
4.3.3.2  Compliance may be confirmed by inspection.  
4.3.4  Stagnation requirements  
The construction of a collector and the quality of the different materials used shall be such that, w hen the 
collector is tested in accordance with RS 213 or RS ISO 9806, to prevent the following : 
a) deformation of any part of the collector;   
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 b) vapour deposition on the underside of the collector cover ; 
c) degrading of paint, sealants, seals or insulation ; and 
d) cracking, flaking, blistering or loss of cohesion of the absorber paint film, shall not be of such magnitude as 
to impair the operation of the collector. This visual evaluation shall be repeated during and at the end of 
thermal properties test in accordance wi th RS ISO 9459 -2. 
4.3.5  Resistance to freezing  
4.3.5.1  A solar water heating collector that is marked as resistant to freezing shall, when tested in accordance 
with RS 213 or RS ISO 9806, show no sign of any damage that could impair its normal operation.  
4.3.5.2  Collectors that include a drain down valve or dumping valve or anti -freeze valve are not acceptable 
methods for freeze protection.  
4.3.6  Resistance to rain penetration  
When the collector of a solar heater is tested in accordance with RS 213 and/or RS ISO 9806, the interior of the 
collector shall remain free from any water penetration and condensation shall disappear within 4 h in dry 
conditions.  
4.3.7  Resistance to fatigue and hydrostatic pressure  
When a collector is tested in accordance with  RS 213 and/or RS ISO 9806, there shall be no leakage or any sign 
of damage or deformation that could impair the normal operation of any of its components.  
4.3.8  Pipe connectors  
Joints between components shall be of acceptable design and quality and shall not leak and shall comply with relevant 
product standards . 
4.3.9  Polymeric materials  
4.3.9.1  Components in contact with hot potable water  
These components shall comply with the relevant material standard requirements and shall be of food grade.  
4.3.9.2  Com ponents not in contact with hot potable water  
Polymeric material shall have been acceptably heat -stabilized and protected from the effects of ultraviolet light by 
incorporation of acceptable ultraviolet (UV) stabilizer in appropriate quantities.  
This shall  be verified by means of a declaration by the manufacturer with supporting technical evidence.  
4.3.10 Sealants  DRS 212: 2022 
7                ©RSB 202 2 - All rights reserved  
 Sealant material shall be suitable for its intended purpose. This shall be verified by means of a declaration by the 
manufacturer with supporting  technical evidence. When tested in accordance with RS 213, the interior of the collector 
shall remain free from any water.  
4.4 Connecting pipe work within the system  
4.4.1  The connecting pipes in the primary circulation loop between the collectors and the storage tank shall comply 
with the relevant approved product standards on plain -ended solid drawn copper tubes for portable water.  
4.4.2  Piping from the tank to the collectors sh all be as short as possible and insulated to reduce heat loss. If the 
collectors are a long distance from the storage tank , pipe insulation shall be increased. . 
4.5 System construction  
4.5.1  General  
All components of a solar water heating syst em including temperature and pressure control equipment shall comply 
with the relevant approved product standards. Installation of a solar water heating system shall be in accordance with 
Annex A.  
4.5.2  Circulation pump  
Circulation pumps in primary loop sh all be suitable for operation with water temperatures of at least 95 °C. This shall 
be verified by means of a declaration by the manufacturer.  
4.5.3  Galvanic action  
Where different materials are joined together or coupled in the same system, acceptable pre cautions shall be taken 
in respect of the choice of materials, the method of jointing and the use of inhibitors, in order to reduce the possibility 
of galvanic action under wet and dry conditions in accordance with relevant standards for water supply insta llations 
for buildings.  
4.5.4  Rated working pressure  
A solar water heating system shall be designed for a rated working pressure of atmospheric pressure, 100 kPa, 200 
kPa, 300 kPa, 400 kPa or 600 kPa, as required. The design and construction of any compone nt or system shall be 
such that, when the component or system is tested in accordance with RS 213, there is no failure that could affect 
the acceptable operation of the component or system.  
4.5.5  Frame and stand  
4.5.5.1  Any stand or frame that carries a st orage tank on top of a roof shall comply with the following:  
a) the stand shall include a structurally sound load spreading support that evenly distributes the loads, on the 
rear legs and that protrudes at least 300 mm past each leg; and  
b) the stand shall inclu de cross braces that stabilize the frame.   
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 4.5.5.2  Any stand or frame that shall determine the angle of the collectors or the storage tank (or both)  
shall comply with the following:  
a) the stand or frame shall allow for the system to be installed at the inclination specified by the manufacturer, 
on any roof pitch as nominated by the manufacturer;  
b) the manufacturer shall provide clear instructions on how to adjust the inclination of the frame. This shall be 
verified by following the instructions provided by  the manufacturer; and  
c) after adjustment the frame shall still comply with all material, corrosion and structural requirements stated 
in this standard.  
4.5.6  Heat transfer fluid  
4.5.6.1  The heat transfer fluid used in an indirect heating system shall be non -toxic and non -corrosive.  
4.5.6.2  Heat transfer fluids should also have a colour added in order to detect a rupture between close and 
open circuits if it happens.  
4.5.7  Electrical components  
Electrical components that are intended to be installed on the ou tside of a building shall be IP32, and effectively 
protected, by means of a corrosion resistant outer casing, against the effects of rain, wind and other elements  
4.6 Thermal properties  
4.6.1  For thermosiphon split systems, the bottom of the storage tank s hall be no more than 350 mm above the 
top of the collector.  
4.6.2  For pumped split systems, the connecting pipes between the collector and the storage tank shall be at 
least 3 m on the inlet as well as on the outlet sides.  
4.6.1  Thermal performance  
When the thermal performance of a solar water heating system is evaluated in accordance with RS ISO 9459 -
2, the daily heat output shall not be less than 5 MJ and not more than 10 MJ per day per 50 l of stored capacity 
at a 20 MJ /m2/ d. 
4.6.2  Standing loss  
When the standing loss of a solar water heating system is determined in accordance with RS ISO 9459 -2, the heat 
loss shall be not more than 20 % of the initial energy. The system shall retain at least 80 % of the energy.  
4.6.3  Mixing factor  DRS 212: 2022 
9                ©RSB 202 2 - All rights reserved  
 When the mixin g factor of a solar water heating system is evaluated in accordance with RS ISO 9459 -2, the 
temperature for the hot water output measured in accordance with 4.6.4, the mean water temperature Tp shall 
be at least 50 °C.  
4.6.4  Hot water output test  
4.6.4.1  Immediately after the standing loss test, switch off the electrical supply. By letting in coldwater, withdraw a 
quantity of water equal to the rated capacity of the water heater at a constant rate of flow.  
4.6.4.2  In the case of open outlet type water heate rs, control the flow using the inlet valve.  
4.6.4.3  In the case of the other types of water heaters, control the flow using a valve fitted in the outlet.  
4.6.4.4  Adjust the rate of flow to:  
a) 4 L/min for water heaters that have a rated capacity of less than 10 L 
b) 10 L/min for water heaters that have a rated capacity of 10 L up to and including 100 L; 
c) 20 L/min for water heaters that have a rated capacity of more than 100 L - 200 L; and  
d) 10 % of the capacity per minute for water heaters that have a rated capacity  exceeding 200 L. 
4.6.4.5  Take continuous temperature readings of the water using a thermocouple placed through and as near as 
practicable to the outlet into the upper half of the water in the container.  
4.6.4.6  Measure the temperature of the withdrawn wat er and determine its average temperature T'p in degrees 
Celsius.  
4.6.4.7  Measure the temperature of the cold inlet water Tc in degrees Celsius. Take the controlled water temperature 
to be 65.0 °C.  
4.6.4.8  Calculate the mean water temperature Tp in degrees Celsius, using:  
45𝑇𝑃 −𝑇𝐶
65−𝑇𝐶+20 
where  
Tc temperature of the cold inlet water  
T p average temperature.  
4.7 Corrosion protection  
NOTE  See Annex B for information on factors governing corrosion and internal scaling of solar water heati ng systems.   
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 4.7.1  Materials in contact with potable water  
4.7.1.1  All materials, including surface protection materials, that are intended to be in contact with potable water, 
shall be non -toxic, shall not  cause the water to become toxic, and shall not impart any colour or objectionable 
odour to the water if tested in accordance with of RS EAS 1 2. 
4.7.1.2  All copper alloy components in direct contact with water shall when a specimen is tested for 
dezincific ation in accordance with RS 213, show a depth of penetration not exceeding 250 μm.  
4.7.2  Corrosion resistance of components  
The material of the component or quality and method of application of surface protection coatings (including 
surface coatings of absorber surfaces), as relevant, shall be such that, when any metallic component of a solar 
water heating system is tested in accordance with RS 213, there is no visible sign of corrosion of the basic 
material or penetration of the surface coat ing. 
NOTE  The test are done in the following sequence, one immediately after the other: Stagnation test for collector, 
Mechanical strength, Resistance to rain penetration, Resistance to hail,  Dezincification resistance, Corrosion resistance, 
Thermal prope rties.  
5 Marking  
5.1 Tank markings  
Each hot water storage tank shall be marked according to RS IEC 60335 -2-21. 
5.2 Collector markings  
All collectors shall be legibly and indelibly marked with the following information:  
a) the manufacturer’s name or trade name  or trademark;  
b) date of manufacture or batch traceability number;  
c) the rated working pressure;  
d) collector model;  
e) the aperture area; and  
f) whether a hail cover is required.  
5.3 Evacuated tube markings  
All tubes shall be legibly and indelibly marked with the following information:  
a) manufacturer’s name or trade name or trademark; and  DRS 212: 2022 
11                ©RSB 202 2 - All rights reserved  
 b) tube model identification  
5.4 System markings  
The system marking shall be attached to a major component of the system and shall include the following:  
a) manufacturer’s name or trade mark ; 
b) system model;  
c) tank name and model;  
d) collector name and model;  
e) freeze resistant status;  
f) specification of transfer fluid and mixing ratio (for indirect systems);  
g) energy rating for standard day (MJ/day);  
h) overnight energy losses (%); and  
i) system type as per 4.1.  
6 Instruction booklet  
A booklet or leaflet in one of official languages used in Rwanda shall be attached to each solar water heating 
system and shall set out the following:  
a) instructions for the safe and correct installation of the complete sola r water heating system, with a 
description of all operating components e.g. collector installations, orientation, piping, electrical 
connections, wiring diagrams, temperature sensors, freeze and hail protection etc;  
b) instructions for the safe and correct op eration of the complete solar water heating system;  
c) instructions for regular maintenance e.g. battery, transfer fluid, sacrificial anode, replacement intervals, 
corrosion prevention and warning details etc;  
d) safety precautions;  
e) relevant technical details of  all major components e.g. collector, tank, electrical components, battery, pump 
etc; and  
f) inclination angle (or range of angles) at which the system shall be installed, and the method of adjusting 
the frame accordingly.  
  
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 Annex  A 
(normative ) 
 
Installation, replacement and retrofit  
A.1 Hot water systems in buildings are regulated by means of the relevant national legislation and local water services 
bylaws.  
A.2 In terms of the relevant national legislation, solar water heating installations are required to comply with the 
following regulations and standards as applicable: Rwanda building control regulations, Regulation on Electrical 
installations in Rwanda, Solar water heating regulations, relevant part of RS IEC 60364 and RS 116 -1 
A.3 New instal lations (where there is no pre -existing hot water installation), and installations in which the existing 
hot water installation is removed and replaced with a solar water heating system should comply with one of the 
options given in table 1.  
A.4 Where sola r water heating installations are retrofitted to existing electrical hot water installations, either a 
solar pre -heater retrofit option (a) or a solar circulating retrofit option (b) given below are suitable.  
A.4.1 Option a) - solar pre -heater retrofit;  there shall be no continual circulation of heated potable water 
between the solar water heating system storage tank and pre -existing electrical storage water heater. The cold 
inlet to the solar pre -heater is connected downstream of the existing pressure cont rol valve, and the hot outlet of 
the solar pre -heater is connected to the inlet connection of the existing electrical storage water heater, not into 
its hot outlet pipe. Flow of solar heated water to the pre -existing electrical water heater only occurs whe n hot 
water is drawn off at terminal fittings. This option may negatively affect flow pressure performance at terminal 
fittings due to the additional in -line friction pressure losses.  
A.4.2 Option b) - solar circulating retrofit;  any appropriate system in table 1 may be used. The circulating 
potable water between the solar water heating system and the existing storage water heater shall be connected 
so that the heated water is circulated between the retrofitted solar water heating system and the existing el ectrical 
storage water heater.  
A.5 In both options (a) and (b) the hot water supply or circulating pipes from the solar water heating system may not 
be connected to the hot outlet pipe of the existing electrical storage water heater. The pressure rating of  the solar water 
heating system shall be matched to that of the existing electrical storage water heater.  
  DRS 212: 2022 
13                ©RSB 202 2 - All rights reserved  
 Annex  B 
(normative ) 
 
Factor governing corrosion and internal scaling of solar water heating 
systems  
B.1 The tendency for metal corrosion or scaling to occu r in a solar water heating system shall depend on the 
characteristics of the water in the system. The evaluation given in B.2 - B.4 may be included to aid in developing 
an acceptable corrosion prevention procedure.  
B.2 A full water analysis should be carri ed out and the Langelier Saturation Index and the Ryznar Stability Index 
calculated to give a guide as to the expected scaling/corrosion tendency of the water.  
B.3 The known performance of metals in a particular water should be ascertained from local user and supplier 
experience and checked against the likely performance as predicted from chemical analysis of the water. It 
should always be remembered, however, that design factors (open circuit, closed circuit, material choice, 
crevices, etc.) may override factors predicted from water chemistry or from the corrosion history.  
B.4 In water with a high chloride or high sulphate content, predictions calculated from a chem ical analysis of the 
water should be treated with caution. It is difficult to define what high chloride content is since this could vary 
from water to water and from metal to metal. The hardness of the water could be an important factor in terms of 
the chl oride tolerance of a metal.  
 DRS 212: 2022 
 
Price based on 13 pages  
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