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Yokohama City University Hospital (Water Supply)

Equipment Outline

Number of Stories:

Eleven stories above the ground and one underground story

Total floor space:

58,424m²

Number of beds:

623 beds

Receiving system:

66kV extra high voltage, two-circuit method using main and spare circuits, 5,000kVA total capacity of the electrical transformer

Heat source equipment:

combination of city gas and electricity
Two 3.6t flue tube boilers, two 4.0t through flow boilers, three 700RT hot and chilled water generators, two 80RT water chiller units

Air-conditioning equipment:

Single duct system by zone, outside air-conditioning machine + fan coil unit, water-cooled packaged air conditioning machine, special air conditioning (germ-free room, reversed air control, and so forth)

Water-supply equipment:

Five 250m³clean water-receiving tanks, three 756m³ water-receiving tanks for miscellaneous use

Hot water-supply equipment:

Two 5,000L hot water storage tanks for high-rise buildings and two 3,500L hot water storage tanks for low-rise buildings, two 2,500L hot water storage tanks for kitchens

Improvement Measures

Total amount of water and sewerage rates at hospitals becomes as high as telephone rates. At this hospital, water supply consumed has been increasing year by year with the improvement of medical equipment and the increase in the number of patients since the opening of the hospital in 1991 and reached a peak in 1995. However, the following measures have been conducted and achieved effects since 1996, the usage of water supply marked a thirteen-percent decrease in 1998 although outpatients increased in ten percent on a basis of the fiscal year 1995.

Main improvement measures conducted

1. Self-closing faucets were exchanged to automatic-closing faucets at forty-two restrooms for outpatients.
2. Makeup water for cooling in boiler blow tanks was reviewed.
3. Humidity setting by seasons was reviewed. (In summer: 50% → 55%, In winter: 50% → 45%)

Data after Improvement