Updating Regulatory Protection of Water Supply Against Contamination by Backflow - Part A ; Updating and Reviewing Regulators' Specifications Against EN Standards - Part B
DWI0846
November 2005
EXECUTIVE SUMMARY - Part A
1. Summary
It has long been realised that available guidance upon the appropriate backflow protection required for protecting the water supply from a downstream risk covers only a fraction of the installations and processes in use within the UK. DEFRA have commissioned this report to expand the available guidance to include installations specified in America, Australia, Europe and the Water Industry agreed fluid risks for installations since the introduction of the Water Supply (Water Fittings) Regulations 1999. The main source of information being from the Water Industry Committees, including the WRAS Test Assessment Group, Technical Support Group and the Technical Committee. The installations or process and its associated fluid risk levels have been collated from these sources and are presented in Appendix A Table 1 with products grouped within generic industry sectors.

The method of categorising the contamination risk in Australia and America is different than that in the UK as they categorise the contaminant risk as High, Medium and Low and specify the exact type of backflow preventer that is to be used to protect the water supply from that specific risk. To enable comparisons between the two methods of risk attenuation and the type of devise specified for the risk the following has been used to determine the level of risk.

AWWA Recommendation UK Fluid Category
Air Gap Fluid 5
RPZ valve Fluid 4
Air Gap or RPZ valve Fluid 4/5
Double check valve Fluid 3
 
Whilst updating the guidance upon Regulatory protection of water supplies against contamination by backflow it became apparent that the method of categorising the level of fluid risk to the water supply from 1 to 5 as specified in the Water Supply (Water Fittings) Regulations 1999 is considered adequate an in-line with the requirements with the European standard EN 1717. However further clarification of the fluid risk categories would ensure a more consistent approach to categorising the fluid risk category.

Table 1 was then circulated to the Water Industry for comment and amended accordingly, the final recommendations for updated guidance on backflow protection is presented as Table 2 in Appendix B.

The matrix or list of installations and the appropriate fluid risk category is not exhaustive and will produce a certain amount of debate within Industry, as comparisons will be made to the table within the published guidance for the Water Supply (Water Fittings) Regulations 1999. The contractor believes that the number and type of installations presented within the matrix will be beneficial in helping the Water Industry enforce the Regulations in a consistent fashion and to help the public to clearly understand their responsibilities when complying with the Water Supply (Water Fittings) Regulations 1999.

2. Background

The Water Supply (Water Fittings) Regulations 1999 (the Regulations) protect public water supplies against waste, misuse, excessive consumption and contamination within plumbing installations of domestic and commercial properties. The Regulations replaced the Water Byelaws, made by the former public sector water undertakers.

Schedule 6 of the Regulations define, in broad terms, 5 fluid risk categories (1-5) depending on the risk the fluid poses if it were to flow back into the water supply system. Examples of installations where each fluid type occurs are given in the Departmental Guidance.

Information on appropriate backflow protection fittings is contained in the Department’s Guidance. Use of Guidance, rather than Regulations, allows more flexible amendment than would be the case under Regulations.

The Departmental Guidance is not exhaustive, as it had been envisaged that clarification of fine detail would be in subsequent guidance.

This approach is consistent with CEN Standard EN1717 (the European Standard on backflow protection). This is because the EN does not directly link risk to product specifications and does not always clearly distinguish risk classes.

However this approach is not ideal in terms of practical application. From a practical point of view a clearer link between examples of installation, the fluid risk category and the type of backflow protection required, or deemed appropriate would be helpful.

The objective is to develop guidance that clearly links type of installation and risk classification with the type of protection required. It is envisaged that this updated guidance will provide authoritative technical advice on obligations for public protection against backflow and will address both whole site and secondary backflow protection.

3. Objectives

Principles underpinning this work are as follows:
  1. identify specific backflow protection devices appropriate for particular installation situations using as models, UK DoE Backsiphonage report, Water Byelaws Guide Schedules A and B, Australian National Plumbing and Drainage code AS 3500.1: 1992 and systems in use in the USA IAPMO UPC National Plumbing Code 1995.
  2. incorporate into the output currently accepted applications against fluid category.
  3. ensure that the output is in a format suitable for inclusion in the Guidance.
4. Whole Site and Zone Backflow Protection

The contactor agreed as part of this research contract to address both whole site and secondary backflow protection. The contractor after discussions with the DWI project manager has agreed that this issue is now being addressed by the WRAS Technical Committee and its Installation and Guidance document 9-04-05 issue 1 dated August 2004. The Technical Committee has tasked a working group to address the Water Industry concerns about implementation, responsibilities and ramifications for maintenance of whole site backflow prevention devices.

5. Appendices

List of appendices
Appendix A - Table 1 installations and risks UK, Australia, America and Europe
Appendix B - Table 2 Completed guidance, installation and risk


EXECUTIVE SUMMARY - Part B

1. Summary

The Regulators Specifications referred to in the Water Supply (Water Fittings) Regulations 1999 Regulation 4.(2)(d) have now been in circulation for Six years and refer to a number of outdated standards and make inappropriate references. This review will recommend the actions required to ensure that only the up to date standards are referred and that inappropriate or superseded Regulators Specifications are deleted.

The majority of the recommendations to accommodate EN’s within the existing Regulators' Specifications that products must satisfy in order to comply with the Water Supply (Water Fittings) Regulations 1999, are minor editorial changes, mainly to align with, and taken directly from, the appropriate BS, BS EN or prEN document. A number of European Standards include the majority of the Regulatory requirements, these European Standards have been used to prepare compiled
Specifications that reference the European Standard and the appropriate clauses within the standard that are considered to prevent contamination and promote water conservation. Specifying the appropriate clauses from the European Standard will ensure that no additional expense or bureaucracy will be placed upon manufacturers seeking to comply with the requirements of the Water Regulations, rather than requiring products comply with the full requirements of the European Standard with no apparent benefit for water conservation or backflow prevention for the Water Industry or the consumer.

Table 1 in Appendix A specifies the actions required to ensure that the Regulators' Specifications refer to the up to date standards, these being a British or European Standard as well as recommendations on deleting Specifications that are considered to be no longer required.

The Regulators' Specifications that have not been compiled require amending to refer to thestandards identified in Table 1 and all references to Byelaws, WRc and all other inappropriate references must be removed.

The conclusions of this review of the Regulators’ Specifications are as follows.
Total Number of Published Regulators' Specifications 216
Number of Regulators Specifications Deleted 47
Number of Regulators Specifications Deleted/compiled 70
Number of Regulators Specifications Amended 7 (12)
Number of Regulators Specifications Current 92
Number of Regulators Specifications Compiled 18 (compiled from EN’s)
Total Number of Regulators’ Specifications 117
 
2. Foreword

This Overview document and Table of required actions contains all information considered necessary to clarify the roles and status of the review of the Regulators’ Specifications against European Standards. In particular, this Overview Document contains the following information:
The majority of the recommendations to accommodate EN’s within the existing Regulators' Specifications that products must satisfy in order to comply with the Water Supply (Water Fittings) Regulations 1999, are minor editorial changes, mainly to align with, and taken directly from, the appropriate BS, BS EN or prEN document. In a number of cases the European Standards include the majority of the Regulatory requirements, these European Standards have been used to
prepare compiled Specifications that reference the EN document and the appropriate clauses within the EN that are considered to prevent contamination and promote water conservation.

Table 1 in Appendix A comments upon the actions required to ensure that the Regulators' Specifications refer to the up to date standards, these being a British or European Standard as well as recommendations on deleting Specifications that are considered to be no longer required.

The Regulators' Specifications that have not been compiled require amending to refer to the standards identified in table 1 and all references to Byelaws, WRc and all other inappropriate references removed.

Because the proposed changes to the Regulators' Specifications are no different from those found within published UK, CEN, and ISO standards and, in some cases, pre-standards, it has not been necessary to liaise with manufacturers and trade organisations upon this review.

3. Background
  1. The requirements of the Water Supply (Water Fittings) Regulations for water fittings are as follows:

    Regulation 4 - (1) (a) requires every water fitting to be of an appropriate quality and standard.

    Regulation 4 - (2) requires that to be deemed of an appropriate quality or standard a water fitting must meet one of four criteria, i.e.: -
  1. it bears an appropriate CE marking in accordance with the Construction Products Directive;
  2. it conforms to an appropriate harmonized standard or European technical approval;
  3. it conforms to an appropriate British Standard or some other national specification of an EEA State which provides an equivalent level of protection and performance; or,
  4. it conforms to a specification approved by the regulator.
The Department had intended that the principal approval criterion would be (b) above - conformity o an appropriate harmonized standard - i.e. a CEN European Standard meeting the requirements of the Mandate under the Construction Products Directive from the European Commission to the European Standardisation Organisation (CEN). The Mandate requires, in essence, that European Standards include for existing regulatory requirements in Member States. Unfortunately no related European standards (ENs) were available in 1999. Therefore, under the provisions of Directive 98/34 EC (which replaced Directive 83/189) all new Regulators' specifications (for WCs and for backflow protection devices) and, all previous Water Byelaws Scheme (WBS) product specifications, were submitted to the Commission of the European Union and were thus agreed by all Member States.

The WBS specifications were envisaged as a stopgap, pending availability of European standards. Because there are now a number of European standards published, the Department has now reviewed the Regulators' Specifications against European standards and makes recommendations to include references to ENs and prEN’s. The review and its recommendations will reduce the number of specification by nearly 50% and will align the remaining Specifications with European
Standards for the published Regulators’ Specifications.

4. Principles

Principles underpinning this work are as follows:
  1. CEN European Standardsഊ3
    Harmonised European Standards will, in due course, replace specific Regulators' Specifications. Initially this will be by incorporating the requirements of the Regulators' Specifications in ENs, as intended by the Construction Products Directive. Subsequently, it is envisaged that Regulatory requirements across Member States will converge by Regulators approximating their requirements, according to the Construction Products Directive.
  2. Water Conservation

    For water conservation, Regulatory requirements must be justifiable in relation to the potential rate of water loss.

    Related requirements in standards, especially draft ENs, have become more demanding in order to meet rising market expectations for quality, durable, and consistent products. This is especially so for levels of durability, such as can now be achieved through modern materials and mass production techniques. In many cases, this will be more demanding than could be justified on grounds of water conservation. This review of the Regulators' specifications has been undertaken of what can be justified for water conservation.
5. The objectives in respect of reviewing ENs and Regulators’ Specification
  1. prepare tables that list all product specifications;
  2. ensure listing of UK Regulators' specifications, includes the Department's for WCs and backflow protection devices, and all others which were adopted from the Water Regulations Advisory Scheme;
  3. identify any Regulators’ Specification, which have been, or are in the process of being, superseded by CEN European Standards, including information on planned or actual implementation dates and on whether the EN/draft EN meets all existing UK Regulators’ Specification;
  4. assess whether, and to what extent, the requirements of the Regulators’ Specification may exceed, or fail to meet, what can reasonably be justified on grounds of water conservation and protection against contamination, such as by what may be construed as requirements for lifetime fitness for purpose.
Note: The objectives of this project do not address the fitness for purpose issues of materials in contact with drinking water.

6. Conclusions reviewing Regulators’ Specifications against EN Standards

After identifying the 87 notified Regulator’s Specifications, a further 129 Specifications have been identified that make up the published Regulators’ Specifications. As part of this review all 216 Regulators' Specifications have been reviewed.

A table that lists all Regulators’ Specifications and the standards referred has been produced (Table 1); the corresponding European Standards including draft European Standards have been referenced if available and comments upon the actions required to update the Regulators' Specifications. The BSi website and the Technical index website have been used as a basis for ensuring up to date standards and information is referred.

It was envisaged that with the publication of European Standards that the Regulators’ Specifications could be deleted and reference made wholly to the appropriate European Standard in its entirety as a means of ensuring compliance with the essential requirements of the Water Supply (Water Fittings) Regulations 1999. However if a reference to the complete European Standard is made then additional test requirements will be imposed over and above those imposed
by the existing Regulators’ Specifications, European Standards generally require flowrate, pressure drop, dimensional, material requirements and acoustic testing. European Standards always exceed the number of requirements than those required by the existing Regulators’ Specifications (but do not necessarily ensure the essential requirements of the Water Regulations are satisfied). European Standards cover fitness for purpose, whereas the Regulators’ Specifications are restricted to preventing contamination and to conserving water. If the Regulators' Specification requires a product to comply with the complete European standard then
this will impose additional expense and bureaucracy upon manufacturers with no additional benefit for water conservation or backflow prevention for the Water Industry or the consumer.

As an example the cost of WRAS approval for a pillar tap would be approximately 950, the cost of testing against EN200 including the acoustic requirement would be approximately 2500.

As part of this review the contractor after discussions with the DWI project manager agreed that only the exact clauses within the European Standards should be referenced within the proposed Regulators' Specifications.

Whilst reviewing the Regulators’ Specifications against European Standards it became apparent that in some generic product groups, particularly Backflow protection, that the number of published or soon to be published standards is considerable. Unfortunately in other generic product groups the publication of European Standards is disappointingly low.

A number of published EN valve standards allow for leakage rates, whereas the existing Regulators' Specifications require products to be leaktight. In these cases when considered appropriate the procedure from the European Standard has been suggested as a replacement with a caveat attached but that the requirement or criteria from the existing Regulators' Specifications is maintained i.e. leaktightness.

Table 1 identifies that there are a total 216 test procedures, of these there are 104 test procedures relating to backflow prevention and WC suites of which 25 have been deleted as they refer to criteria that have been superseded by the Regulators’ Specifications for WC suites or the appropriate European Standards for backflow. From the 216 procedures, 47 test procedures have been deleted, 70 have been compiled, 7 require fully amending (12 amendments total) or replacing
references to the standard. The remaining 92 test procedures are considered to be current and therefore require no amendment.

The conclusions of the review of the Regulators’ Specifications are as follows if the recommendations of this report are implemented.
Total Number of Published Regulators' Specifications 216
Number of Regulators Specifications Deleted 47
Number of Regulators Specifications Deleted/compiled 70
Number of Regulators Specifications Amended 7 (12)
Number of Regulators Specifications Current 92
Number of Regulators Specifications Compiled 18 (compiled from EN’s)
Total Number of Regulators’ Specifications 117
 
7. Justification for amending and deleting test procedures

As part of this review of the Regulators’ Specifications the proposed amendments that are made to the Specifications are to be justifiable in that they provide a benefit for Water Conservation or prevention of contamination. However the degree of Water Conservation that can be achieved by products connected to the domestic supply may be extremely small per product installed, but the number of products installed countrywide will be enormous. Therefore benefits of zero leakage being a Regulatory requirement can have an extremely large impact upon water conservation countrywide.

Justification for amending the test procedures includes the removal of references to withdrawn or superseded standards these being either BS or BS EN documents. If references are made to superseded or withdrawn standards then these are highlighted in the index table and the appropriate standard referenced. If the test procedure within the up to date standard is more onerous than the test procedure already available and the procedure is still considered valid then the existing test procedure can be retained but the reference to the withdrawn or superseded standard number should be removed from the Specification.

8. European standards that include the majority of the Regulators' Specifications.

Whilst producing the table comparing the existing Regulators Specifications against European Standards it became apparent that European Standards do not incorporate all the existing Regulators’ Specifications. However a number of EN’s accommodate the vast majority of the Regulators’ Specifications and are listed below.
The existing Regulators’ Specifications generally list a single test procedure along with the acceptance criteria for a generic type of water related product, the full list of Specifications to be applied to the water related product are then specified by WRAS in their product test report documents. This method of specifying test criteria i.e. individually and not listing all the test criteria to be applied to that generic product is not satisfactory. With the advent of European Standards that now contain the majority of the Regulators’ Specifications within the standard the contractor believes that a number of the existing Regulators’ Specifications can now be compiled or collated to produce a single Specification for a generic product type. This will not only benefit the manufacturer of the water product but also the Regulator, as the number of Specifications will be greatly reduced.

These compiled Specifications will make reference to the applicable European Standard and the applicable clauses within that standard that the product must comply with in order to verify compliance with the Water Supply (Water Fittings) Regulations 1999, Regulation 4.(1)(a)&(b). This approach will enable the manufacturer of the water related product to more easily ascertain the Regulatory requirements that their product must comply with.

It was agreed that the complete European standards listed above be referenced within the Regulators' Specifications and that the existing Regulators' Specifications referring to these devices be deleted. The existing Regulators' Specifications for these devices will be referred to being compiled into a single Specification in Table 1.

The European standards listed above do not incorporate all the Regulators Specifications but these Specifications are still required for products installed within the UK and will still be required to be referenced within the compiled Specifications, the Specifications are listed as:
The compiled specifications are presented in Annex B

The date reference of the European Standard has not been recorded within the compiled Specifications presented (Appendix B). European Standard are amended every 5 years and if significant changes are made then the clause numbers will change and the references within the Regulators' Specifications will then refer to inappropriate clauses. Consideration must be given to referencing the year of publication of the European Standard. Whichever method is agreed there
will be some cost incurred in ensuring that the Regulators’ Specifications remain current.

Generic products compiled 22, however the building valves standards (5) can be incorporated into one specification, therefore 18 new compiled Specifications will be presented. Existing Regulators’ Specifications compiled and therefore considered to be deleted 70.

Regulators’ Specifications reduced by 52
.
9. Appendices

List of appendices

Appendix A - Table 1, actions required to update the Regulators’ Specifications.

Appendix B - Compiled Regulators' Specifications

Copies of this report may be available as an Acrobat pdf download under the 'Post 2000 Reports' heading on the DWI website.