My concern with much Health and Safety orientated legislation is that it seems to do more to protect bureaucrats from criticism in the event of a tragedy, rather than the alleged beneficiaries. The article quotes Government Minister Phil Hope (Office of the Deputy Prime Minister) who intends to seek regulation of temperature on the supply to high risk sanitary fitments on new build and conversions (England and Wales). The matter was also reported on by the BBC recently.

As responsible Installers will know, there is already sufficient control built in to new build dwellings and has been for many years now. This is achieved with thermostats which can of course be altered by householders or in some cases I have noted, accidentally disturbed when cylinder cupboards are stuffed with clothing being aired. I acknowledge various devices have been employed by manufacturers to prevent accidental disturbance of settings but there are other risks.

I recall attending one address (new build) which had suffered extreme hot water temperature for a long time despite the best efforts of others to resolve the problem. No one had checked the back-up immersion heater which had evidently been left switched on from day one. That was set at 800C. The spur switch did not have a neon indicator light which might have helped.

Although failed (thermostat) immersion heaters is a problem which must be known to most Installers (I had three last year) only recently has it received public attention in a tragic case reported on last year, in which a woman died and her partner was seriously hurt. I had an almost identical case years ago where I entered the roof space at an address as the plastic cold water tank started to collapse with boiling water. Two minutes later arriving and a baby in a cot directly under that tank would have become another statistic. Had I arrived one minute later the tank may have collapsed as I was in the roof space before opening taps and moving the cot, thus I might have been blamed for a tragedy not of my doing.

I had another case in December 2003, this time at a restaurant. The thermostat failed on the free standing three year old boiler. The feed and expansion tank is now seriously distorted and weakened from boiling water. For some reason they have used a huge cold water storage tank as a feed and expansion tank. They were alerted to the problem by airlocking pipes. If the thermostat fails again the tank will collapse over the middle of the dining area, spilling far more boiling water than a standard feed and expansion tank. Written reports on the matter remain unheeded and there is nothing more I can do about that except hope.

In the latter case an overheat device could be introduced and any replacement tank sited in a position where it would not cause injury if it failed. Hot water at restaurants is typically maintained at an excessively high temperature to meet kitchen needs, often because their volume needs have grown but the system has not been upgraded to cope with increased volume. Invariably hot water delivered to the sanitary fitments is uncontrolled and off the same supply. Warnings fall upon deaf ears.

Many or indeed most restaurants illegally house (resident) staff in conditions that fall well below minimum levels of decency. Fire is the biggest risk in my view but if such accommodation was legal there would be a need for a Landlords Gas Safety Check in many cases. Sanitary conditions are usually poor and in some cases, showers are lethal. This arises often because in prosperous areas, affordable accommodation is in short supply and owners will not buy or rent suitable humanitarian accommodation. It is only a matter of time before there is a serious and preventable tragedy amongst the most vulnerable in society, who do not have a trade union in support.

Is there a risk on new homes ? Potentially I have to say yes. Whether new homes feature in accident statistics I do not know. We never receive that sort of information. Designers calculating heating load (boiler size) traditionally work on a maximum of 600C and recommend a setting of 550C for hot water. However, thermostats can be adjusted so that water theoretically could reach the 820C maximum boiler flow temperature.

Showers on new build have traditional been the mixer-flow type which could be induced to deliver scalding water if scalding water was available. Properly fitted they cannot however suddenly become hot, only cold. I think it unlikely that accidents arise from this cause but I don’t know for certain. Lately house builders have adopted thermostatic showers. There is however risk from the less sophisticated bath / shower mixer taps which are now popular.

Low cost and entry level housing tend to have ordinary taps. The proud owners then rush out to the DIY store to buy bath / shower mixer taps. Such installations are invariably illegal as the cold feed is not tank fed. Aside from the risk of scalding if someone draws cold water elsewhere while a shower is in use, there is the risk of flooding. Flooding is not often seen but when it is, it is always spectacular. Mains pressure cold water drives up the tank fed hot water supply causing the tank to overflow.

I went to a call-out one day where a DIY change-over had gone wrong. I was asked to repair a leak but had to refit the old taps as the new bath / shower mixer taps were illegal on that installation. Aside from safety there is the Water Supply (Water Fittings) Regulations. That couple spent over £150.00 at the DIY store and received no advice. It should be incumbent upon all merchants to supply information to purchasers of any apparatus which may be misused accidentally through ignorance. This should include all terminal fittings (taps etc) automatically. If safety is really seen to be important, prove it. I am not yet convinced.

Consumers wishing to connect showers to their hot water supply must present a merchant or DIY store with precise information on how their hot water is sourced. Many showers will not work satisfactorily with combination boilers and/or multipoint water heaters. I have seen much disappointment under this heading. If you are thinking of changing to a combination boiler, check your shower before you use it, unless it is an electric shower.

Installers or consumers who would like to research further information should visit the Thermostatic Mixing Valve Manufacturers Association (TMVA) website. A new generation of Thermostatic Mixing Valves (TMV2) has been developed for domestic use. Advice to consumers purchasing terminal fittings must include information about the TMV2 in future to protect DIY installers.

Consumers wishing to introduce hot water temperature control to an existing (usually gravity hot water) system will find complete information on The Association of Controls Manufacturers Association (TACMA) website. Their publication in support of Part L of the new Building Regulations is particularly succinct and useful. The publication is available here also as a pdf file.

Whilst it would not be realistic to regulate for the TMV2 with domestic maintenance work, it should be incumbent upon merchants (and Installers) to supply relevant advice to consumers at the point of sale of all terminal fittings. Any legislation would otherwise possibly have negligible impact upon accident figures. All suppliers of goods have a duty to ensure products are not only fit for their purpose but appropriate. The matter is not without legal precedent.

Failure to legislate accordingly might suggest a preoccupation with GDP rather than safety.