Building Regulations Approved Document G
Chris Taylor-Hamlin, Technical Director of the award winning Bathroom Manufacturers Association, takes a look at Building Regulations Part G and particularly to hot water safety.
It was on 10 March 2010 that
Approved Document G of the Building Regulations
The new regulations heralded a step change in bathroom safety, helping to reduce
scalding accidents which result in over 20 deaths and over 200 scalding accidents
in the UK bathroom every year, a shocking statistic by any standard. Its importance
is reflected in the number of pages given over to it in the Approved Document.
Part G3, hot water supply and systems, occupies a full 10 pages of the total 48.
This section of Part G in the technical guidance ‘embodies the need to provide
hot water to baths, bidets, showers, washbasins and sinks’ and ‘extends measures
to ensure safe operation of all types of hot water systems.’
The document goes into great detail about hot water systems and how they should
be installed for maximum safety. It talks about the design and installation of directly
or indirectly heated hot water systems and the need for suitable pipework which
will withstand very high temperatures and pressures. With an eye to the future
and the need for energy efficiency it specifically mentions requirements for
instantaneous electric water heaters and solar water heating. It also states that
good workmanship is essential.
'It’s the new requirement for the prevention of scalding by the installation of devices
which limit the temperature of water supplied to the bath
which is so important' says Taylor-Hamlin.
Baths in all new homes must be fitted with a Thermostatic Mixing Valve (TMV) designed specifically to limit the temperature of hot water. The valve must be set at a maximum 48°C and ‘should be compatible with the sources of hot and cold water that serve them.’ There is a reminder in the document that in some buildings (eg care homes) additional performance standards are required of the TMVs.
TMVs, themselves, are the subject of a number of British and European Standards and the regulations require their compliance with BS EN 1111:1999 or BS EN 1287:1999. These devices must ensure that the maximum temperature is not exceeded, cannot be easily altered by the building user, and that they should ‘fail-safe.’
'The regulations obviously only apply to new or materially changed dwellings’ says Taylor-Hamlin, ‘but they are also used as a benchmark for good plumbing practice. The BMA is always looking for ways to improve safety in the bathroom.
We now need to make ALL householders aware that this relatively inexpensive device,
the TMV, can be retro-fitted in ALL homes and will prevent scalding,
particularly in the elderly and very young.’
An excellent publication from the BMA provides an in-depth and informative guide to the Thermostatic Mixing Valve. The guide is a valuable resource and goes into great detail about the product; what it is, where it can be used and what are the relevant regulations.
The text and excellent images bring home the importance of the TMV. The guide, in PDF format, is downloadable from the BMA’s Bathroom Academy website. www.bathroom-academy.co.uk