A community hospital facility relies on crucial standards being maintained around the clock.

Although remarkable advances continue in medical science, surgical procedures and patient care, hospitals can still be dangerous places to stay.

This is well demonstrated globally by the increasing number of patients contracting diseases they didn’t have when they entered hospital.

In consultation with readers, WPI decided it would be of value to the industry to compare how plumbing designers globally are tackling onsite plumbing issues in the everyday construction of new hospitals of varying sizes in several countries.

There was no intention to turn this into a competition. Rather, the aim is to note similarities or differences in how various design and practical plumbing problems are solved. Sharing information is the central objective of this magazine.

Along the way we discovered some interesting ideas and solutions that will be valuable to readers working on similar projects in future. Our appreciation goes to the plumbing engineers/designers who helped us with this challenging editorial task.

Doutor Arnaldo Hospital, Brazil

In the Brazilian city of Sao Paulo, construction of the new general-purpose Doutor Arnaldo Hospital, with 733 beds, has been completed at a cost equivalent to US$150 million. The hospital consists of 28 floors, four of which are below ground level.

Hydraulic and mechanical services for the project were designed by the Sao Paulo consultancy MHA Engineering– including cold and hot water systems, fire hydrants and sprinkler systems, stormwater systems, medicinal gases, mains gas reticulation and diesel fuel systems.

According to MHA civil engineer Marcia Brandao Da Silva, challenges were confronted in designing and installing the hydraulic and mechanical services to fit with the architectural design of the building.

“The biggest difficulty with this project related to the ribbed slab structure and sewer system that was already in place,” she said.

“We spent a lot of time liaising with the architecture team and changing the position of bathrooms and sinks in order to provide effective access to the sewer below.

“Another problem was the restricted size of the ceiling areas, which meant that special attention had to be given to ensuring that the large volume of installations could be accommodated in the space available.

“An all-copper potable water reticulation system was installed together with seven connected storage reservoirs fed from the public system by pumping to the top reservoir. Total capacity of the reservoirs is 2.2ML (581 million gallons), and the top reservoir also has a 170m3 (45,000 gallons) reserve for fire service purposes. Each reservoir has two independent cells to enable maintenance without shutting down the system.

“All potable water is chlorinated in the public supply system before being filtered on site, but backflow prevention devices are not installed. As part of the Pura (Rational Water Use) Program, drain water from the air-conditioner towers is collected and returned for reuse in the same system. In addition, water-saving toilets with a 6L (1.6 gallons) flush are installed, together with flow restrictors in each faucet and shower. Under the Brazilian plumbing code, a maximum pressure of 40mca is specified for hot and cold water.

“The central flow and return hot water system is installed on the second floor below ground. Because of the height of the building there are three separate systems to provide pressure control – one each for high, medium and low pressure – and one for the kitchen and employee changing room.

“The hot water system consists of four storage tanks (two each of 3,000L and 5,000L, or 790 and 1,320 gallons) and three Raypak water heaters capable of providing 8,000L (2,115 gallons) per hour. Fabrimar thermostatic mixing valves (TMVs) are installed in the bathrooms to control hot water temperature, and Tour Andersen TMVs are used in the distribution lines to balance the system.

“About 27km (17 miles) of cast-iron pipe is installed at the hospital for the wastewater and stormwater collection systems. All wastewater is discharged to the sewer main for treatment at the public wastewater treatment facility. Stormwater is collected from the roof via a Saint Gobain Epams system and transported by gravity to the public sewer mains.

“An important part of the total project was the installation of a medicinal gases delivery system to the preparation rooms, surgery room, intensive care unit and internation rooms. Components of the system included all-copper piping together with 4,300 points to deliver nitrous oxide and oxygen, plus points for compressed air, vacuum and CO2.”

Da Silva says designing plumbing services for a hospital is very satisfying, but it requires a strong continuing focus to ensure all services will be efficient and reliable. This includes the continuing availability of the MHA team in case any final adjustments to plumbing-related installations are needed after the project is finished.

Children’s Oncology Hospital, Egypt

Located in Cairo, a city of about 15 million people, the Children’s Oncology Hospital is the first integrated hospital of its type to be constructed in Egypt. It provides services for children and their families throughout the Middle East, as well as for other countries in Africa.

Before construction began, audits of treatment facilities in the region revealed that many hospitals were not child-friendly, particularly in relation to cancer patients. The new hospital will cater for children’s medical and recovery needs with the modern oncology procedures and cancer support services common in Western countries.

The facility is being built for the Association of Friends of the National Cancer Institute by a consortium including the Arabian Construction Company and Siemens under a contract equivalent to US$38 million. Siemens is providing the electromechanical requirements such as electrical systems, air-conditioning, plumbing and fire protection systems.

This project is one of the first to be totally financed by donations from Egyptians as a national charity initiative for children with cancer.

Located in parkland, the 50,000m2 (538,000ft2) hospital will consist of two main buildings. The first has been designed as a bed tower that will house more than 200 beds on six levels, and the layout incorporates large waiting rooms to accommodate entire families when they visit sick children.

Patient comfort is a high priority, with the area of each floor totaling 1500m2 (16,000ft2). During children’s recovery, parents will be able to stay overnight, usually in the same room.

There are already plans to expand the complex to include a guesthouse for visiting relatives from remote locations, plus establishment of the first in-hospital school in Egypt.

The second building will consist of three stories to accommodate diagnostic equipment and treatment facilities, including radiation, surgical, oncology and support services. Again, space is a feature, with each floor having a total area of 4500m2 (48,500ft2).

Other non-medical services such as car parking, kitchen and laundry are incorporated into the basement and ground floor levels.

GHD’s Cairo hydraulic team leader, Walid Yossef, says the water supply system includes a 165m3 (43,5000 gallons) storage tank in the basement. It is filled by a 150mm (6in) make-up water feeder line from the external municipality network, with water coming mainly from the Nile River.

Three domestic booster pumps (two active and one standby) are located in the basement mechanical room to provide flow to the water treatment plant, which consists of four sand filters, four water softeners and two chlorination systems.

“A central water-boiling system is located on the second floor and includes two steam boilers each with a capacity of 200bhp (150kW), a de-aerator, a condensate surge tank and steam to water heaters,” Yossef says.

“All toilets, washing basins and showers are supplied with hot water at 68ºC (155ºF) by using two steam-to-water heaters in the second floor boiler room.

“Hot water for the kitchen is also provided at 68ºC via a steam-to-water heater at ground floor, and hot water for the laundry is supplied at 70ºC (158ºF) from a steam-to-water heater in the basement.”

Other installations include vacuum and compressed-air systems, and a galvanized steel pipe network to transport medical gases.

Design of the wastewater drainage system is based on a one-pipe system that includes a combined stack for blackwater and graywater in addition to a separate vent stack for each discharge.

All horizontal and vertical pipes are no-hub cast iron, and all discharge from higher floors by gravity to external manholes and then to the main sewer line.

Basement floor drainpipes go to a sump pit in the basement floor where two submersible pumps convey the flow through a forced main to the gravity pipes in the basement ceiling. There is a separate sump pit and two submersible pumps for garage waste at basement floor level.

A special separate drainage network collects all chemical waste and drains it to a neutralization pit before discharge to the main sewer line.

Stormwater collected at roof drains flows through storm stacks to the main sewer line via gully traps. As Egypt experiences low rainfall, stormwater treatment is not provided.

Columbia Asia Hospital, India

Construction of the 90-bed general purpose Columbia Asia Hospital in Bangalore was recently completed at a total value equivalent to US$16.5 million.

Design of the plumbing and firefighting services for the project was undertaken by Potential Service Consultants, a plumbing consultancy practice in India.

According to the firm’s principal consultant, B.S.A. Narayan, the main challenge faced during the project was dealing with technical coordination of various services.

“This was generally sorted out by holding workshops involving other relevant consultants and service providers,” Narayan says.

“In relation to the potable water reticulation system, galvanized steel pipes with malleable iron (galvanized) fittings were used for ring and branch mains. However, for super specialty hospitals in India, copper plumbing is also used, and a new trend is to use CPVC pipes and fittings.

“Backflow prevention devices are not installed, as this is a stand-alone system.

“A two-day capacity storage for domestic purposes and a static storage for firefighting are installed on site. This is to guard against the absence of a continuous supply of water and inadequate pressure in the city mains. System pressure required is 2.5-3kg/m2 (about 0.6psi).

“The type of water treatment normally depends on the source of the water. If the supply is from city mains, we specify basic treatment comprising pressure sand filter and activated carbon filter, followed by disinfection. If the source is other than the city main, the treatment shall be as per the water analysis.

“Flow and return and reverse return systems featuring hot water generators fired by oil or gas are used to produce hot water. Solar power is used for pre-heating the water for the hot water generators, and distribution piping is insulated to reduce heat loss and save energy.

“To deliver tempered water, normal control valves are used with a plate-type heat exchanger, mixing tank and circulation pump.

“For the wastewater collection system, UPVC pipes and fittings with a solvent welding system are utilized, together with cast iron pipes and fittings. Effluent treatment is via a below ground plant that uses a membrane bio-reactor in an EA and AS process. Specialized bio-medical waste is disposed of as per government regulations to central incinerators. Some of the recycled water from the wastewater treatment plant is used for toilet flushing.

“Our strong focus on water saving included the installation of dual-flush 6/3L (1.6/0.8 gallons) water-saving sanitary units, and there are limits on the designed output parameters of faucets.

“Stormwater from the hospital roof is collected via roof gullies and down-take pipes. The pipes are RCC Hume, and the system also has RCC open drains in some places. Collected stormwater is treated separately then reused for toilet flushing and cleaning purposes.

“In addition, treated stormwater is used for recharging groundwater, which is used for landscape watering.”

Narayan says hospital projects can be challenging because a lot of care and dedication is required from the plumbing designer, particularly in relation to the design and installation of specialized plumbing services. Potential Service Consultants is working on two more hospital projects in India for the same clients.

Bathurst Base Hospital, Australia

Bathurst is a regional city about 200km (125 miles) west of Sydney, New South Wales. It has a population of 40,000 and also serves a much larger surrounding rural population.

The project was initiated and funded by the New South Wales Government to update the original hospital, and the new facility now provides entire emergency, operating, paediatric and recovery services for the people of the district.

Because the new hospital was replacing the existing one, a staged demolition was required to maintain the hospital as a working facility. Some heritage buildings were retained and later used for non-core medical facilities.

With a total construction value equivalent to US$82 million, the hospital accommodates 149 beds and extends over three levels and an approximate area of 23,600m2 (254,000ft2). Facilities include three operating theatres, acute medicine, imaging and pathology.

Built by John Holland Constructions and operated by the NSW Health Department, this State Government project did not require local government approval. However, it was a requirement under the design brief that the design should comply with local council requirements.

Reference guides/codes used were AS 3500 (Australian/New Zealand Plumbing Code) and the NSW Code of Plumbing Practice. Under AS 3500, all materials must meet relevant Australian Standards or carry WaterMark approval.

The building structure consists of concrete slabs, external brick walls, metal stud internal walls with drywall/plaster, and metal roof.

Under project management arrangements, the builder selected the plumbing contractor after a tendering process, and the contractor supplied all materials and labor as required.

All plumbing design and supervision was undertaken by Sydney-based hydraulic consulting firm Michael Frost & Associates.

In relation to potable water supply, mains-pressure water of good quality is available from local dams via the council water main grid. With incoming pressure of 500-600kPa (about 11,000psi), no pumps were required for domestic supply or fire services. Also, no onsite storage of water was required due to the provision of a tanker back-up service by the local council in case of emergency, such as a mains breakdown.

Although the general quality of the water is excellent, all water is filtered and chlorinated on site via a continuous-flow filter. The filter to the main incoming water supply is an SAD 750S 10-micron multimedia automatic backwashing sand filter operating in parallel with a side stream chlorine control system.

Ring mains on the water services have control valves to enable segments of the mains to be shut down for maintenance purposes while supply is maintained to the rest of the hospital. Piping for ring mains is copper (25-100mm, or 1-4”) and XPLE (15-20mm, or ½-¾”) is used for branch lines.

The main plant room for hot and warm water systems is on the rooftop and consists of two combustion gas boilers and four hot water storage tanks of 340L (90 US gallons) each.

Two systems are supplied from these storage tanks. The warm water system is supplied via a Rheem Guardian warm water unit with thermostatic mixing valves (TMVs) and a UV sterilizer. This system provides controlled temperature water from the plant at 43.5ºC and returns at 40.5ºC (110ºF). Methodical testing is carried out every six months on the warm water system to ensure the absence of legionella.

The other flow and return system sharing the same tanks provides hot water flow at 65ºC (150ºF), which returns at about 60ºC (140ºF). This system services facilities such as kitchens and dirty utility rooms, as well as the paediatric (babies) unit via TMVs to control the temperature at a maximum of 38ºC (100ºF).

TMVs used are Enware Aquablend 1500, which are approved by the State Health Department and tested every 12 months.

In medical areas, all tapware is wall mounted with lever-type action, and conventional handles are used in public bathrooms. Backflow prevention devices are installed at the property boundary for site containment, and other backflow devices are located at specific facilities on the site.

Piping for sanitary plumbing is uPVC, which is insulated in habitable areas, and uPVC is also used for in-ground drainage. HDPE with electro-fusion jointing is installed for trade waste and high-temperature discharge pipes (eg: from commercial dishwashers).

No sump pumps for stormwater or sewage were necessary due to location of the hospital on the side of a hill, thus enabling gravity feed to the relevant council mains.

Wherever possible, the design for sanitary plumbing used 45-degree bends and clean-out points to the floor above. These are chrome-plated 100mm diameter access points, normally connected to the WC pan drainage below the floor for easy pipe cleaning in the event of a blockage. In an occupied room, this obviates the need to access drainage via the ceiling of the floor below.

Toilet pans are all skirted-type enclosed dual-flush 6/4.5L (1.6/1.2 gallons) water-saving units, and urinals are wall hung with solenoid and beam activation.

Fire services

For fire services, galvanized iron with vitaulic joints is used for above-ground requirements, and PE is installed for below-ground services. All in-ground metal piping is sleeved in a continuous plastic envelope and taped at the joints to guard against corrosion from any reactive soil.

The Bathurst Base Hospital project also included construction of a roof-top helipad, and the client brief had a requirement to design a spill-control system in case a helicopter fuel tank ruptured or there was an accident on the pad.

The consequences of such a situation could be disastrous for the hospital and the surrounding environment.

Although such facilities are becoming quite common, the engineer could not find a specific Standard or code, so he had to come up with his own solution. His plan features an HDPE drain line that discharges any aviation fuel and stormwater from the pad to ground level via a separate drainage system.

It then enters a pit that has a hydrocarbon sensor which, on sensing the fuel, shuts the valve to the stormwater system and diverts any fuel into an isolated underground storage tank.

Here a float switch sets off an alarm indicating the need for the tank to be emptied and decanted off site. Equipment (pit) for this system is supplied by www.foxenviro.com.au

According to hydraulic systems designer Michael Frost, the most challenging aspects of this project were, as with any hospital project, the sheer extent of services required in such a building and the need to coordinate with other services in tight ceiling spaces.

“Specific client needs in each room had to be catered for,” Frost says.

“Each fitting, and the respective service requirements, had to be carefully coordinated to ensure the end result is correct. Hospitals, more than any other building, are about teamwork in the design consultancy to ensure a successful project.

“The one specific item that was a challenge was the helipad drainage system, which had to be separate from the other drainage systems and of a material to cope with about 2,000L (530 gallons) of aviation fuel.

The system must also be able to cope with a major storm at the same time and have the ability to identify a spillage or ruptured fuel tank so there is no discharge to the local stormwater system, hence to the local river to which it discharges.”