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For many years the NHS guidance notes, in the form of the health technical memorandums (HTMs), have underpinned the design of healthcare premises in the UK. However, today's consultants and specifiers aiming to embrace excellence in healthcare design may experience difficulties if they follow HTMs with the same reliance as they did in the past. New technologies and new procurement strategies have overtaken many of the HTMs, some of which were developed more than 10 years ago.

Although the guidance is constantly being revised (see the Forthcoming technical guidance sidebar), the pressure on the NHS to introduce and manage its investment programme over the next 10 years via the PFI, Procure 21 and LIFT means it is understandable that the HTM upgrades are lagging behind.

So for those consultants and specifiers who want to incorporate innovation in their designs, there is a danger of coming into conflict with those who approve healthcare buildings in accordance with HTMs. It's not surprising that many specifiers and consultants choose to play it safe and steer clear of any innovation likely to contradict a particular HTM guidance.

One area of concern is energy guidance and how it conflicts with the goal of designing hospitals in which staff can operate efficiently. An example is the April 2002 guidance note, Sustainable Development in the NHS, which quoted energy targets for hospital construction. To meet the targets hospitals must be designed with a narrow plan to ensure lots of natural daylight and a minimal need for mechanical ventilation. But many hospitals are now being designed with deep plans as it enables related departments to be sited next to one another. This results in reduced daylight, increased artificial lighting and the potential need for comfort cooling.
Below is a sample of HTMs in need of updating:

HTM 2011 Emergency Electrical Services 1993
The cost-saving practice, called peak lopping, of switching to standby generators when the amount of electrical energy being used approaches a higher tariff band is becoming standard. By allowing the standby generator to be switched into operation, the hospital can avoid financial penalties associated with certain tariffs. This HTM was written when electrical generators were used purely as a standby in case of power cuts. Those following the guidance in the current HTM may find their standby and bulk fuel storage systems insufficient to provide a peak lopping facility.

HTM 2007 Electrical Services Supply and Distribution 1993
The stated level of essential electric sockets in this HTM is often inadequate for the latest user requirements. Essential sockets are those that have a backup power supply in case of a power cut and are used for essential equipment such as life support systems. Traditionally, a 50% essential/50% non-essential electrical socket was considered appropriate but now clients often want the flexibility of 100% essential sockets, so that medical equipment can be moved between powerpoints. Although the HTM alludes to the need to increase the essential supply to 100% of the demand, definitive guidance to designers should be offered.

HTM 2022 Medical Gas Pipeline Systems 1997
The Medical Gas Association is revising oxygen requirements for healthcare facilities. The changes relate to risk assessment and the provision of secondary and emergency supplies (in case of failure of primary supplies), which is in line with European standards.

HTM 2025 Ventilation in Healthcare Premises 1994
The document needs to be reviewed in light of available technologies, particularly the use of packaged ventilation plant. Packaged units are small and can be connected on site. They are factory tested and take up less space than the traditional air-handling units illustrated in the HTM. The modular system is popular in many other European Union countries. This "plug and play" technology will not only offer standardisation but could reduce installation and commissioning time.

HTM 2055 Telecommunications 1994
Since this was introduced there has been an IT revolution. A revised HTM should take into account electronic patient records systems, picture archiving and communication systems, bed-head communication technology and patient entertainment, and wireless technology. A number of facilities are supporting this new technology but the HTM does not give clear guidance on the specification requirements. phil.nedin@arup.com