Changes to the Building Regulations are heavily focused on energy efficiency but Bob Towse, head of technical and safety at the HVCA, says safety must not be compromised.
The Building Regulations are back in focus as the consultations for the new Parts L and F are now in full swing. The need to keep pushing energy efficiency improvements is, of course, vital but we must not lose sight of the safety issues.

Part G (sanitation, hot water safety and water efficiency) has already been amended so that, from October 2009, all new homes must have protective devices fitted to baths that limit hot water temperatures. This is a welcome development in our attempts to reduce injuries from hot water scalding but it also highlights a wider problem.

Last year I highlighted the tragic case of little Rhianna Hardie, who died because the thermostat on her family's immersion heater failed and continued to heat the water in the cylinder well beyond a safe temperature. Hot water was vented into the cold tank in the loft, which eventually burst pouring scalding water down on to the sleeping baby below. This was a product failure in an existing home, which shows how ongoing service and maintenance is an important factor in reducing risk to life and limb - regulations aimed at new homes cannot tackle this.

Although all new immersion heaters now have additional overheat protection built in, there are still several million homes in the UK thought to still be at risk because they have old style units.

Wastage

Hot water is generated and stored at temperatures of no less than 600C in most domestic properties, primarily to guard against the build up of legionella bacteria. Higher temperatures also mean it is possible to use smaller storage cylinders to cut water wastage and reduce energy consumption. However, this means that most of the water in our homes is kept at a temperature that can cause scalding.

Anything above 450C can lead to injury and once you are above 600C it is possible for serious harm to be caused in just a few seconds. Using thermostatic mixing valves (TMVs) allows engineers to design systems that store water at relatively high temperatures but dispense it safely.

Other countries have had regulations governing TMVs and immersion heaters for some years and their experience shows that serious injuries can be reduced by as much as 50% by widely deploying anti-scald technology.

+The HVCA, along with other industry bodies, favours legislation calling for on-going maintenance of hot water systems to ensure they are retrospectively fitted with TMVs or other methods of controlling the temperature of the water that emerges from our taps.

Detailed guidance is available in the HVCA's Domestic Central Heating Installation Specification document, which gives safe temperatures for a range of appliances.
It is relatively easy to regulate for new installations, but tackling existing systems requires more imagination.

Companies in our industry must also play their part by being vigilant whenever they are called on to service heating systems.