Safe, secure power for hospitals

Citation

(2001), "Safe, secure power for hospitals", Facilities, Vol. 19 No. 7/8. https://doi.org/10.1108/f.2001.06919gab.003

Safe, secure power for hospitals

Safe, secure power for hospitals

Keywords: NHS, Hospitals, Energy management, Health and safety

Nuffield Hospitals is currently embarked on a £1 million programme to install safe, uninterruptible power to critical areas in all its hospitals, in accordance with the Department of Health's recommendations.

"It is unthinkable that the lives of patients should be put at risk by power cuts or electric shock during operations or while in critical life care", comments group engineer for Nuffield Hospitals David Storrs. "No hospital can afford a mortality due to an unsafe power supply. It is a testament to the quality of our patient care that Nuffield hospitals are among the first in the country to equip for safer power."

IEC regulations covering electrical installations in medical locations are at draft stage. These refer mainly to hospitals, but could also apply to private clinics, medical and dental surgeries, health-care centres, and dedicated medical areas in the workplace. Until the IEC regulations become binding, Health Technical Memorandum HTM 2007 – Electrical Services: Supply and Distribution (1993) provides guidelines in the UK. The HTM emphasises that a hospital electrical distribution system should be designed to provide security of supply and flexibility and safety in operation. The recommendations of the Department of Health are now normally implemented for hospital newbuilds and refurbishments.

"In accordance with the recommendations, we're incorporating isolated power supplies in hospitals currently under construction or refurbishment", David Storrs continues, "and we have proactively made the decision to instal uninterruptible power supplies at all our hospitals for the safety of patients."

Safe power

In normal circumstances electric currents in the order of 25mA are sufficient to cause a loss of normal heart muscle rhythm, which may be fatal. However, the natural protection of the body is considerably reduced during certain clinical procedures. For instance, during open heart surgery or in the use of conductive catheters, currents as low as 10A are considered to carry a risk. The ever-increasing use of electrical equipment on patients under acute care therefore demands enhanced safety of electrical installations.

Hospital rooms concerned include operating theatres, operating preparation rooms, heart catheterisation rooms, intensive care rooms and angiographic examination rooms.

Reliable power

HTM recommendations also point to protection against mains failure of devices used for life support, diagnosis or treatment. Where power protection is concerned, there are guidelines for various transfer times to standby power, depending on the criticality of the application. A no-break power supply is recommended for most microprocessor controlled equipment.

A strategy for patient safety

"The HTM started to generate awareness of the problems three or four years ago", David Storrs continues. "Taken alongside logical health and safety considerations, the guidelines prompted a business decision some 18 months ago to develop a programme for increased electrical safety in our hospitals. Our main push has been on UPS, with 40 sites scheduled to be equipped. Our Warwickshire hospital was the first to be equipped with an IPS/UPS installation supplied by Uninterruptible Power Supplies Limited."

David Storrs identified cost of ownership among the most important criteria for choosing a UPS supplier: "We evaluated tenders for the Warwickshire installation on the basis of five-year running costs, as well as the provision of back-up services. Uninterruptible Power Supplies offered the best overall package of capital cost, cost of ownership and maintenance."

An IPS/UPS package

For the Warwickshire Nuffield, Uninterruptible Power Supplies provided an isolating transformer IPS with load and leakage current monitoring and alarms. The design of this system isolates the earth from both lines, so that a dead short to earth or leakage current will not trip the circuit breaker, so ensuring continuity of supply to the equipment. However, patients or staff accidentally touching a line will not experience any harmful leakage current. The UPS sits between the mains supply and the IPS.

Uninterruptible Power Supplies' competitive bid was enabled by the company's PowerWAVE UPS technology. Launched last year, PowerWAVE uses transformerless technology and unique input stage design to provide the highest efficiency in an online UPS together with near-unity input current power factor for minimum running costs. A 60kVA PowerWAVE 5000 UPS protects all sockets in operating theatres and selected sockets elsewhere in the Warwickshire hospital. Although the hospital is equipped with an emergency generator, the decision has been made to instal one hour's autonomy on critical outlets as a "belt and braces" safeguard against generator failure.

Nuffield Hospitals is currently making a decision on an appropriate maintenance contract, but with a choice of options right up to 24 hours a day, 365 days a year, with four-hour call-out, its requirements will be met by Uninterruptible Power Supplies, however exacting. The company has already become involved in training the Warwickshire's electrical engineers in system operation.

Continuation of Nuffield Hospitals' strategy for safety involves a short-term project to retrofit 30 hospitals with UPSs. "Our objective is to have all systems fitted over a 15-working week period", David Storrs concludes. "So, with fast response added to our other selection criteria, this is a very demanding contract for any UPS supplier!

"We are pleased to announce that Uninterruptible Power Supplies' bid has again been successful, and installations started at the end of November. Since future capital schemes will spec power protection equipment from the same supplier, the award of this contract is an unequivocal statement of our confidence in the company."

The UK's leading independent supplier of turnkey power support systems, Uninterruptible Power Supplies offers hospital facilities managers, their consultants and contractors an expert design, installation and back-up service for safe, secure power. With combined IPS/UPS capability, the company can provide a coherent solution with the potential to limit costs and reduce the management burden on hospital staff.

For further information contact Peter Bentley, Uninterruptible Power Supplies Limited, Bacchus, Calleva Park, Aldermaston, Berkshire RG7 8EN. Tel: +44 (0) 118 981 5151; Fax: +44 (0) 118 981 5152; E-mail: sales@upspower.co.uk; Interact: www.upspower.co.uk