Please note there is a new version of this leaflet HERE
Using lead-free solder for drinking water fittings
How to avoid health risks from lead solder and flux contamination of water
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Contents
- Who should read this leaflet?
- Risks from lead
- What the Water Supply Fittings Regulations say about lead solders
- Advice on using a plumber
- Advice to DIY plumbers installing water supply fittings
- Risks from excess flux - copper contamination
- Further advice
Who should read this leaflet?
If you are renovating your home, or you are a professional or DIY plumber, a builder or a property developer, this leaflet tells you what you need to know about avoiding health risks and complying with the law on lead solder.
Risks from lead
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Lead exists in the environment. It comes from a variety of sources including some vehicle exhausts and old paintwork. It may be present in air, food, soil or water. Lead can build up in the body and can be harmful. It is sensible to avoid excessive exposure from any source.
Some older houses have lead water pipes. The Drinking Water Inspectorate (DWI) has published a free leaflet called 'Have you got lead pipes?'. DWI contact details are on the back of this leaflet.
But there is another potential source of lead in water. If someone installing drinking water fittings uses lead solder, then the level of lead in the water can be harmful to health in some areas of water supply. In addition, the flux used to help the flow of solder into the joints, can cause contamination of water with lead and copper if left in the pipes. This is particularly true of the aggressive self-cleaning type of flux.
The potential health risk posed by lead means it is vital to raise awareness of the need to meet high standards when soldering joints. Installers should follow the detailed advice on making soldered joints in the Copper Development Association (CDA) publications 33 and 88. You can get copies by contacting CDA on 01442 275700 or through its web site at
www.cda.org.uk.What the Water Supply Fittings Regulations say about lead solders
It is illegal to use lead solder when installing fittings to be used with water for drinking, washing or preparing food. Water supply byelaws and more recently the Water Supply (Water Fittings) Regulations 1999 have banned the use of lead solder throughout England and Wales for over 15 years.
However, lead solder can still be safely used for some plumbing works where the water is not for drinking or cooking, such as in closed circuit heating systems.
Installers and users of water systems are legally obliged to comply with these Regulations, including the requirements for lead solder. Water suppliers must ensure that the Regulations are met. They do this by inspecting the plumbing systems of a sample of new and existing properties.
Property owners, builders and developers should insist that plumbers abide by the Regulations and use the right materials. If they don't, they risk a court summons and a fine.
- Use only lead-free solder in drinking water installations
- Look for 'lead-free' on solder labels
Advice on using a plumber
Choose a plumber who understands the regulations
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Use a plumber or contractor who is approved under the Water Supply (Water Fittings) Regulations. An approved plumber will provide a certificate that the work on your drinking water installation meets all regulatory requirements - including the use of only lead-free solder. To find an approved plumber, contact:
www.plumbers.co.uk.
- your local water company; or
- The Institute of Plumbing, on 01708 472791 or through its web site at
Does your plumber have the soldering information leaflet?
Check that your plumber has read the UK Copper Board's leaflet on correct soldering, which is available from their web site at www.ukcopperboard.co.uk.
Checking water supply installations
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If you suspect that lead solder has been used on your recent installation, you can ask an approved plumber to carry out a test. You should contact your water company, who can also analyse the water and advise you what to do if they detect lead solder.
The Water Regulations Advisory Scheme (WRAS), which works on behalf of all water suppliers, also provides further information. Please see the 'further advice' section below for contact details.
General advice
In new homes or where plumbing has been modernised there may be newly soldered joints. The plumber should thoroughly flush the system to get rid of any installation debris - although flushing may not always remove all excess flux.
Water should not be left standing for a long time between installation of a plumbing system and its first use. The system should be completely drained and then flushed, or preferably someone should run the water frequently to change it within the system, while it is new.
You should briefly flush regularly during the first month of service to help wash out any metal particles picked up from the pipes and joints, and minimise any problems from excess flux.
You are also advised to briefly flush the plumbing system each time you use it before drawing water from the tap for drinking or for food preparation.
Advice to DIY plumbers installing water supply fittings
Buy the right solder
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The label should state that the solder is 'lead-free'. If you are uncertain, ask a store assistant for advice. You can get non-leaded jointing solutions such as an integral solder ring, which is guaranteed to use lead-free solder. You can also use push-fit and press-fit fittings that do not need heat.
Some basic soldering tips
Soldering joints involves cleaning, fluxing and assembly, heating and finishing off. You must be aware of all the basic practical steps to ensure a safe installation. You can get further advice from the UK Copper Board at
www.ukcopperboard.co.uk. Only apply the minimum solder and flux necessary to do the job. Generally, you should only apply flux to the pipe. Once you have finished soldering, flush the pipes well to remove flux, copper particles and other debris.
Risks from excess flux - copper contamination
Excess flux can cause copper levels to exceed the standard of three milligrams per litre laid down by the Water Supply (Water Quality) Regulations 1989. The Water Supply (Water Quality) Regulations 2000 impose a stricter standard of two milligrams per litre. These regulations will come into force in 2003. In addition, the 2000 regulations classify copper as a toxic metal.
Where copper concentrations persist above three milligrams per litre and the mains water is not excessively aggressive towards copper, you will probably need to replace the pipes or soldered joints to comply with the standard for copper.
Further advice
info@wras.co.uk or through its web site at www.wras.co.uk. WRAS has a Water Supply Industry Approved Installation Method (AIM) giving water industry guidance, entitled 'Solders and Fluxes'.
- The Water Regulations Advisory Scheme can advise you further on the Water Supply (Water Fittings) Regulations on behalf of all UK water suppliers. Contact WRAS on 01495 248454 or by e-mail at
For further information on general water quality and lead, contact the Drinking Water Inspectorate. The contact details are on the back of this leaflet.
Other Leaflets
- What do we do?
- How Good is the Drinking Water ?
- Chlorine, Smell, Taste
- Discoloured Water
- Lead in Drink Water
- Private Water Supplies
- Problems with your Drinking Water
- Water Hardness
- Tap Water, where does it come from and how is it made safe to drink?
- DWI Summary Reports on each water company
Printed versions of the above leaflets are available from us free of charge
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Drinking Water Inspectorate,
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Telephone : 020 7944 5956 - Facsimile : 020 7944 5969
E-mail: dwi.enquiries@defra.gsi.gov.uk
Published 10 July 2002
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