Stop Hot Water Scalding at Home

We all know the feeling, you turn on the hot water tap to wash your hands and you immediately regret it as you get a splash of scalding and painful hot water. Scalding hot water injuries should not to be overlooked, as they account for severe injuries and sometimes leading to fatal ones.

In autumn 2007 the Health and Safety Executive has introduced new directives for care homes. According to the new directive they have to install thermostatic mixing valves and make them temper proof. This latest development follows a tragic case of a fatal injury from scalding water.

The Scottish Building Standard already requires all new property developments and major refurbishments to install thermostatic mixing valves. Although not compulsory in the rest of the UK at the moment the Building Regulations in the UK are working towards adding it in a future update.

To reduce the risk of Legionella, it is required to keep hot water (for example within a hot water tank) at temperatures of between 60 and 65 degrees Celsius. At these temperatures it is believed that the Legionella virus does not survive. Nevertheless, water coming out of the tap at that temperature is too hot and should be mixed with colder water first.

The mixing valves are particularly important in communal water heating systems and public building. The requirement to keep water at a high temperature to reduce the risk of Legionella all the way to the point of distribution can create a risk of scalding if a TMV is not present.

There are primarily two groups of users at risk of burns - young children and old people. Every year UK hospitals admit hundreds of children that suffer from burns from extra hot baths. Children have a very sensitive skin and such burns may leave scars for the rest of their lives. Similarly, old people get scalded from extra hot water when their less sensitive skin and slow reactions may hinder their movements thus exacerbate the injury. Mentally and physically impaired people are also slow to react or easily confused under such circumstances leading to injuries.

There are primarily two types of thermostatic mixing valves that are certified and approved for installation:

TMV2 kits are mostly used for domestic installations. However, they are also suitable for most other properties. It is required to undertake a full risk assessment to review if there are disabled or vulnerable people on the premises.

TMV3 valves are engineered to tighter performance and provide better safety and quality. They are required in all installations in healthcare projects or on premises for disabled or vulnerable people (such as mentally or physically challenged people).

Manufacturers of thermostatic mixing valves recommend that they are installed only by qualified plumbers. The valves are positioned between the hot and the cold pipes to prevent the water coming out of the tap at an extremely high temperature. Most common TMVs are installed under the bath or under the hand basin for a simple installation. Most kits are sold with tailpieces which include isolation, a strainer and test points. Some kits have flexible connectors and isolating filter vales to deal with space limitations.

Stop Hot Water Scalding at Home - Install TMVs