Instructions for Use requirements (Advice Sheet 2)

Version 6.0, April 2023

Glossary

1. Introduction

The Instructions for Use (IFU) document is an integral part of the product approval. All test requirements specified by the DWI for assessment of the products potential effects on water quality will be based on the IFU document. This ensures that the testing carried out reflects, as closely as possible, the intended application and use of the product by a water company.

After an approval is granted the IFU is a mandatory requirement to be provided to the water company and their third parties who will be using the product for use in contact with water intended for human consumption. Failure to follow the approved IFU document, as detailed in the List of Approved Products is a breach of the approval and could result in prosecution. All instances of failure to follow the IFU shall be reported to DWI as an event under the event reporting procedures.

Products are considered, assessed and tested on the basis of your IFU and any final approval given makes it a legal requirement to adhere to the IFU.

2. Content of the IFU

The IFU should be comprehensive, up to date, describe its installation, use and any associated requirements the product may need for use in the supply of water intended for human consumption.

2.1 General Requirements

The content of the IFU will vary depending upon the nature of the product and the mode of use. As a minimum, however, the document must contain the following:

• be a formal, comprehensive self-contained document which is identified by title, issue number, date of issue and contact details with each page numbered sequentially
• be product specific and including the scope of use of the product, but can cover a range of similar products from the same materials and components
• relate specifically to the installation and use of the product under the requirements of Regulation 31
• specify the conditions of use which will apply when the product is approved, including details of any storage conditions, unloading requirements and preparation requirements
• use metric units; alternative units can be provided within brackets after the metric unit
• include the accepted UK use of a period for a decimal point and a comma or space as a separator for thousands, e.g. 1,234.5 or 1 234.5
• describe how the product will be installed
• provide details of routine checks on performance in operation, if applicable
• disinfection details, if applicable
• disposal and fate of the product
• details of the factory manufacturing process for product to be supplied to DWI as a separate document

The rest of section two deals with the specific requirements for certain product types that require inclusion the IFU document.

2.2 Site Applied Materials

In addition, for site applied products (including in-situ linings), it must:

• indicate methods of surface preparation
• describe the packaging and identification of multi-component parts, including the colour of each part and the finished lining/coating colour
• include the following details of the application process for each layer (including primers and undercoats)
• the mixing process, including mixing ratios, how its undertaken and pot life
• method of application (for example brush or spray)
• minimum temperature of application and any environmental controls and humidity restrictions
• give details of curing conditions including

      cure period

      temperature

      relative humidity (if applicable)

      cure curves

• include details substrates the product can be applied to and of any known incompatibilities with potential substrates onto which the product could be applied
• include details of how repairs can be undertaken
• In-situ applied linings for water mains must be applied in accordance with the requirements of the Water Industry Information and Guidance Note IGN 4-02-02 “Code of Practice: In-situ resin lining of water mains” and the Water Industry Specification WIS 4-02-01 “Operational Requirements: In situ resin lining of water mains” or Water Industry Specification WIS 4-02-03 “Operational Requirements : In-situ polymeric lining of service pipes” available from Water UK. These documents refer to specific information that must be included in the product Instructions for Use.

2.3 Pipes

In addition, the IFU should include:

• physical dimensions of the product range (using the same materials and methods of manufacture) for which approval is sought
• jointing including mechanical, solvent welding and heat welding instructions as appropriate or reference to Water Industry Specification WIS 4-32-08 “Fusion jointing of polyethylene pressure pipeline systems using PE80 and PE100 materials”
• for lined pipe, instructions for repair of defects prior to installation and/or during installation, including making good at joints and any future repairs

2.4 Tanks, Reservoirs and Pressure Vessels

In addition, the IFU should include:

• physical dimensions of the product range for which approval is sought
• installation and assembly instructions including details of all ancillary equipment and components, e.g. ladders, roof stays, access points, jointing and sealing compounds used in assembly
• for lined products, instructions for repair of defects prior to installation and/or during installation, including making good at joints and any future repairs

2.5 Treatment Chemicals (including disinfectants and cleaning agents)

In addition, the IFU should include:

• any preparation prior to usage (e.g. dilution) and details of all commissioning procedures undertaken by the end user
• method, control and point of dosing at point of use
• the maximum, minimum and maintenance dosage rates, where applicable
• test methods to determine chemical concentration and dose strength
• routine monitoring of dose strength requirements for the product
• storage conditions and shelf life
• procedures to be adopted before, during and after use
• any restrictions on the use of the product and associated by-products that would cause contamination of the water supply
• details of conformity to any relevant national standards

2.6 Adsorbents, Filter Media and Ion Exchange Resins

In addition, the IFU should include:

• type of adsorbent, media or resin material
• details of product size and range
• any specific product preparation prior to installation and use
• conditioning procedures (e.g. flow rates, pH stabilization, bed volumes)
• maintenance procedures (e.g. regeneration of the product)
• expected life cycle, including any monitoring requirements (e.g. exhaustion, regeneration, end of life)
• details of conformity to any relevant national standards

2.7 Electrochemical Generation Products

In addition, the IFU should include:

• all installation, operational, maintenance and cleaning details, including full details of chemicals used
• expected shelf-life of the generated product
• include all details of generated by-products and contaminants
• details of UK biocidal Product Regulations status and compliance to any relevant national standards
• schematic diagram of the product

2.8 Membrane Systems

In addition, the IFU should include:

• explanation of the water type for which the unit has been designed, e.g. brackish, partially treated etc., and the suitability of the system for use with chlorinated water
• all installation, operational, maintenance and cleaning details
• details of the preserving system(s) used
• the commissioning instructions should include:
• die-away curves which demonstrate the volume of water and rinsing times required to completely remove any traces of preserving fluids from the unit
• a means of verifying under plant conditions that removal of these fluids has been effectively carried out
• typical minimum and maximum flow rates
• typical volume of water treated before the membrane is taken out of service for cleaning
• cleaning instructions should include (as appropriate):
• details explaining when cleaning is required
• information about any cleaning chemicals used
• the procedures and die-away curves for the use and then removal of cleaning/disinfecting agents
• the volume of raw or treated water to be used in backwashing and cleaning
• a means of verifying that under plant conditions removal of these agents has been effectively carried out
• details of any on-line dosing of chemicals (e.g. descalants) and evidence of their removal
• typical life before replacement is needed

2.9 Emergency Equipment

In addition, the IFU should include:

• proposed use, including details of all associated ancillary equipment required, whether provided with the product, or obtained locally, any specific labelling requirements, and length of service
• all installation, operational, maintenance and cleaning details, includes any monitoring and testing requirements
• assessment of status before deployment, including state of packaging and any tamperproof seals etc
• appropriate reference to regulation 6(3) of the Water Supply (Water Quality) Regulations 2016, and how the requirements of this will be met in use.
• One-use products must specify that the product must not be re-used
• Multi-use products must include relevant post-use cleaning and storage requirements

3. Structure of the IFU

The text of the IFU should be set out in headed sections that reflect the sequence the user needs to follow in order to understand the proposed use of the product, its introduction into use, continuing operation and safeguards for drinking water quality. The guidance should be in a logical sequence making use of headings and sub-headings, and using schematic drawings and photographs when these will help the user.

An indicative structure is given below that includes all the elements of this guidance, as appropriate for the product. It is emphasised that this guidance cannot be prescriptive due to the diversity of products and their uses. Please ensure that you submit the following additional product information with your application.

• Description of the Product and Use – Describe what the product is, including physical and chemical parameters. Describe what the product is used for, including the scope and restrictions on use by drinking water suppliers.
• Product Application – Describe how the product is used. It will probably help the user if this section is set out with sub-sections which may include product packaging and delivery, assembly, component mixing, application methods, curing etc.

If the product can only be applied or installed by specific contractors, this requirement will be included as a condition of approval. If the product application requires staff to work in restricted areas they should have a National Water Hygiene Card.

• Commissioning and Preparing a Product for Use, Including Disinfection – This will include instructions on any cleaning, flushing and disinfection routines, together with any checks and tests to ensure the product is fit to be put into use. As chlorine is commonly used for disinfection it is important that you describe any conditions on the maximum allowable exposure of the product to chlorine both by concentration and contact time.
• Operational Routines – Any routine monitoring, performance checks and routine maintenance should be described. A detailed maintenance manual is not required but attention should be drawn to routine measures that need to be taken to ensure the satisfactory and effective use of the product. Procedures for the stopping and re-starting of product use should be included.
• Storage – Conditions for product storage together with its shelf life should be described.
• Disposal – Requirements for disposal, including any specific neutralisation required for chemicals.

4. Useful Reference Documents

• Civil Engineering Specification for the Water Industry, published by WRc plc on behalf of UK Water Industry Research Ltd
• Principles of Water Supply Hygiene & Technical Guidance Notes, Published by Water UK and available from, http://www.water.org.uk
• Relevant WIS and IGNs for example:-

      Water Industry Information and Guidance Note IGN 4-02-02 “Code of Practice: In-situ resin lining of water mains”

      Water Industry Specification WIS 4-02-01 “Operational Requirements: In situ resin lining of water mains”

      Water Industry Specification WIS 4-32-08 “Fusion jointing of polyethylene pressure pipeline systems using PE80 and PE100 materials”