Electrical and Life Safety Upgrades of Historic TerminalSystems

Description

TMG Construction Corporation was the General Contractor responsible for a variety of upgrades to mission-critical systems at this historic terminal, which was constructed in the early 1940s and is listed on the National Park Service’s National Register of Historic Places. Key components of the project included replacing medium voltage electrical feeders and switchboards, fire alarm upgrades and the installation of a new fire protection system. Particular sensitivity was given to performing the work in a manner that preserved the historic integrity of the facility throughout the modernization and up-grades.

More specifically, the scope included replacing the redundant electrical service to the terminal including the replacement of two 4,160v feeders and a two-compartment switchboard. This portion of the work was made challenging by space limitations in the existing electrical equipment room and by a requirement that electrical service not be interrupted to the terminal building. To this end, TMG, its subcontractors and the suppliers of the switchboards spent considerable effort documenting the as-built physical dimensions of the existing switchgear. Thereafter, the challenges included designing and fabricating new switch gear equipment that would fit the existing space, provide additional clearances and meet engineering requirements brought about by updates in the National Electric Code. To maintain uninterrupted electrical service to the terminal, new equipment was fabricated in such a manner that the old equipment could be removed and the new equipment installed in a piece-by-piece manner. All of these objectives were accomplished.

The second challenge was to upgrade the analog fire alarm system to integrate it into the Siemens MXL digital Fire Alarm System servicing the remainder of the campus, notably to transfer control of the fire alarm system functions from the old system to the new once it had been commissioned and actively on-line. To accomplish this, TMG developed a complex phasing sequence in the construction schedule to systematically commission and energize the functionality of the new system (i.e., transfer of control of HVAC equipment). Work was complicated by the need to perform selective asbestos removal.

The third component of this project involved providing fire services, constructing stand pipes, and installing an automatic sprinkler system for parts of the terminal that previously did not have fire protection. To accomplish this, TMG selectively removed and replaced architectural elements of the building, allowing work to progress around existing conditions and minimizing any impact on the historic aspects/ appearance of the building.