TMVs - Protect your Family from Scalding Hot Water

It happend to all of us. You turn on the hot water tap to wash your hands and 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, sometimes even 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.

Scottish Building Standards already include a requirement to install thermostatic mixing valves on all new property developments and major retrofit projects. The rest of the UK is not currently requiring this, but the Building Regulations body is reviewing this issue at the moment.

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.

The most vulnerable groups to scalding are the very young and the very old. Every year hundreds of children are admitted to hospital with burns from an extremely hot bath. Children have a very sensitive skin which gets burned very easily and leave a scar for life. On the other extreme, old people's skin is not as sensitive to hot water and their reactions are not as quick, especially when needing to turn off an extra hot water tap quickly. Another group that may be at risk are physically or mentally impaired individuals that suffer from slow reactions and slow response time.

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 designed for higher performance to offer the maximum safety levels. TMV3 valves are required for all healthcare premises, or premises with disabled or vulnerable people (such as mentally or physically handicapped people).

Most manufacturers of thermostatic mixing valves recommend qualified plumbers for the installations of their kits. For a qualified plumber, the kits are easy to install between the hot and the cold pipes to ensure effective mixing action. Most kits are designed for a simple installation under the bath or under the sink and include several important components. At typical kit includes tailpieces with isolation, a strainer and test points. To handle installation in limited spaces, there are kits with a flexible connector and isolating filter valve.

Article Archive

Tags :

RSS Feed :