News

A Westchester Classic
June 28, 2005

By Staff
Appeared in Engineered Systems

The medical gas system components are distributed through the children’s hospital complex to various in-patient, clinical, and trauma departments, with only waste anesthetic gas disposal, nitrous oxide, and nitrogen used in the operating rooms. The oxygen tank farm was expanded, with a 9,200-gal primary oxygen tank and a 3,000-gal reserve tank to serve both the new hospital and the adjacent Ruth Taylor Institute, with a valved and capped future backup line for the existing main hospital.

Creating a state-of-the-art children’s hospital requires innovative solutions that meet current and future needs of the facility. Sensitivity to the health and emotional needs of the children and families who use the facility is also a critical component of such a project. An example is the $85 million, 250,000-sq-ft Maria Fareri Children’s Hospital on Woods Road at the Westchester Medical Center in Valhalla, NY.

One of the primary challenges facing the project team was to find ways to alleviate the stress of hospitalization for children and their families through design solutions. To accomplish this task, the project’s design team, a tri-venture of architects NBBJ and Lothrop Associates and MEP and life-safety engineer, Syska Hennessy Group of Manhattan, created a distinctly child-friendly environment. For example, the outside of the facility has a very non-institutional look, appearing to be a large house to make children feel at home. In fact, since family, fun, and laughter contribute to the recovery process, a small park and a miniature golf course were constructed outside this new “house.”

Designed as a child-friendly environment, the facility has numerous features intended to appeal to and amuse children. Lighting fixtures were chosen to create a soft nature/home-like ambiance. The lighting and HVAC systems were integrated into hospital displays, including the lobby’s 5,000-gal fish tank, an authentic locomotive, a large doll collection, the David Cone/New York Yankees sports arcade, an actual fire engine cab, a resource center, a stage, a toy store, and a food court.

The third floor includes private rooms for parents. These suites, which are equipped with kitchens and dining areas, are part of a built-in Ronald McDonald House that allows parents of an ill child to stay overnight.

Complex Utility Relocation
The design team was challenged prior to the start of construction when the owner wanted the new children’s hospital sited on Woods Road so it would be prominently visible to passersby. Fulfilling this request required that the new three-level facility be located on top of the existing main hospital’s utility tunnel. The solution was to relocate all of the utilities while keeping the main hospital operational. To achieve this, the utility tunnel was intercepted by constructing a new entrance outside the footprint of the new children’s hospital. This took careful planning and phasing to keep the main hospital operational as utilities were switched over.

Provisions were made in the tunnel for utilities to serve the children’s hospital. New valves for the steam and hot water were installed along with new junction boxes for the electrical service and terminal boxes for the telecommunications lines.

Before the children’s hospital could be constructed, two existing buildings totaling 100,000 sq ft needed to be demolished. Prior to demolition, hospital staff and personnel (as well as patients who had been located in these two buildings) were relocated in a series of 30 moves to new, permanent space created in the main hospital and adjacent buildings.

As this task proceeded, other efforts were underway to make the hospital state-of-the-art and expandable for future needs. These focused on the HVAC, electrical service, life-safety and security systems, all of which were tied into the new building’s automated controls.

Integrating Major Systems into the Design

Major building systems in the children’s hospital include three chillers and 13 air handlers of various sizes. High-pressure steam is brought into the hospital from the utility tunnel at 125 psi. In order for the steam to be used for sterilizers at 60 psi, a pressure-reducing valve was installed. It was further reduced to 15 psi for the perimeter heating system, duct reheats, humidifiers, and steam preheat coils.

Major building systems in the children’s hospital include three chillers. One of these is a 500-ton electric drive chiller and two are 500-ton gas-fired absorption chillers. The hybrid system was chosen to take advantage of the efficiencies of differing units at varying loads. There are also two 1,250 kW diesel generators, located in the penthouse and supplied by a 10,000-gal fuel oil storage tank. Provisions were made for space to accommodate a third generator at a future date.

In addition, 13 air handlers of various sizes were installed in keeping with the child-friendly “house” theme of the hospital’s design. To achieve this, the units were located in the “attic” space beneath the hospital’s peaked roof. This solution made excellent use of space while conforming to the architects’ design.

High-pressure steam is brought into the hospital from the utility tunnel at 125 psi. In order for the steam to be used for sterilizers at 60 psi, a pressure-reducing valve was installed. It was further reduced to 15 psi for the perimeter heating system, duct reheats, humidifiers, and steam preheat coils.

In order to plan for any electrical service disruptions, a redundant feeder system was developed and brought in from the utility tunnel. Each 15 kV feeder can carry the full load of the new building. Two 15 kV primary selector switches serve two 3,000 kV step-down transformers for 480 V/277 V for distribution throughout the new hospital building.

Providing redundancy for the project’s domestic hot water system required the use of a separate gas-fired, 3,000-gal, 3,200,000-Btuh, 3,200-gph unit. This is a recirculating system that is fed from the hospital campus central plant building. It comes into the new building at 140°F and is stepped down to 120°. It is then recirculated through a back-up water heater that is located inside the new children’s hospital and is normally off. Should the main source be interrupted, the back-up system will become operational.

The medical gas system for the new hospital consists of oxygen, medical vacuum, carbon dioxide, nitrogen, nitrous oxide, waste anesthetic gas disposal, and medical air. The oxygen system was challenging because there was an existing oxygen tank farm, which proved to be inadequate for current and future needs. The solution called for expanding the oxygen tank farm with a 9,200-gal primary oxygen tank and a 3,000-gal reserve tank to serve both the new hospital and the adjacent Ruth Taylor Institute with a valved and capped future backup line for the existing main hospital.

The medical gas system components are distributed throughout the children’s hospital complex to various in-patient, clinical, and trauma departments. Waste anesthetic gas disposal, nitrous oxide, and nitrogen are only used in the operating rooms. The natural gas system is a dual-pressure setup that was brought into the new building to serve the absorption chillers, domestic water heater, and vent free fireplaces that have oxygen depletion sensors. All areas with gas-fired equipment are provided with gas detectors.

Building Management Controls
Like all of these new systems, the fire alarm system is also linked to the BMS. The structure is fully sprinkled with a state-of-the-art fire alarm and smoke exhaust/smoke purge system that separates the building into smoke zones and floors. This includes smoke and heat detectors, speakers, strobes, and pulls stations.

The automated BMS controls all of the mechanical equipment as well as a series of dampers that open and close as programmed. The system has been designed to monitor electrical and plumbing systems so that costs can be evaluated with regard to maintenance and labor.

Overall, the project advanced state-of-the-art engineering by demonstrating how engineers can provide cost-effective, technically sound solutions that improve the quality of life for all building occupants including the children and their families. The project served to reinforce the benefit, with respect to schedule and cost, of creating a collaborative design between the engineer, architects, owner, and other consultants. Since MEP systems have such a tremendous impact in the design of all hospitals, having input on the makeup of these systems from the very beginning enabled the project team to resolve issues as the design was developed. This allowed the architects to design with the full knowledge of how the mechanical, electrical, plumbing, fire protection, fire alarm, life safety, and BMS integrate with the design of such a complex facility.

This all-specialty children’s hospital, which was completed in September 2004, is the only hospital of its kind in the region, serving the entire Hudson Valley, lower Connecticut, and the northern New Jersey area. It is home to some of the world’s finest pediatric specialists as well as the region’s only Level III neonatal and pediatric intensive care units, pediatric open-heart surgery units and cardiac catheterization centers. It also contains a specialized high-risk obstetrics center.