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Design – Case Study 2


Client Need


A 7,000 SF renovation to an existing lithography facility was required for this high tech client. The design and construction required a phased approach (4 phases total) to minimize or eliminate impact on adjacent production areas that were to remain active until renovated under a separate phase. The project included the utilization of an existing 15,000 CFM air handling unit with a new fully integrated energy recovery system. A new heat and polishing mist exhaust system was designed, which included a centralized moisture elimination system with energy recovery capability. Extensive process piping and plumbing systems and distribution were required throughout the project including coordination of future piping racks serving a future addition.

Design Features

  • Basis of Design setpoints: 75 °F (± 1 °F) and 40% RH (± 5% RH) year round.
  • Full sequence of operations for all new equipment including all interface points with existing equipment and systems.
  • Designed modifications to the make-up air component of an existing 15,000 CFM air handling unit to receive make-up air from the new energy recovery system.
  • Designed new exhaust system with centralized moisture elimination and energy recovery capability serving facility equipment, new spray booth and new fume hoods.
  • Designed and detailed piping racks coordinating 20 different process and plumbing piping services through tight tolerance ceiling spaces (ceiling heights at 12 feet from finished floor and structural deck at 16 feet from finished floor), which also included both new and existing supply, return, and exhaust ductwork. Piping racks served both the project scope area and a planned future addition.
  • Designed and laid out new wet vacuum system including moisture separation and connection to existing house vacuum system.
  • Designed custom process waste lift station assemblies serving sinks. Lift stations included high velocity sump discharge to scour piping system. Process waste discharge followed by hot water purge of the system.
  • Designed and laid out new process cooling water system including selection of new pump, three-way control valve and filtration. Process cooling water system sized to handle ultimate load of current project and future addition.
  • Designed and laid out new ordinary hazard, group 2 wet pipe sprinkler system and modified existing system for conformance with code.
  • Designed and laid out electrical distribution systems including branch circuit panels, transformers, and feeders. Voltage drop on feeders designed were not to exceed 3% and total voltage drop for feeders and branch circuits were not to exceed 5%.
  • Designed power for all HVAC and process mechanical equipment including feeders, disconnect switches, and motor controllers.
  • Designed power services for all facility equipment installed in new spaces.
  • Designed and laid out all fire alarm services including interface with existing system.
  • Designed lighting using appropriate clean room fixtures recessed into ceiling grid system. Designed and coordinated automatic lighting control system with owner and architect and as required by code.

Design Benefits

  • Critical production areas have tightly controlled, year round temperature to ±1.0 °F and relative humidity to ±5% RH
  • Cascade pressure relationship between critical and noncritical areas to prevent infiltration and molecular contamination
  • Achieved a robust production facility capable of operating continuously year round while maintaining strict environmental criteria
  • Fully integrated energy recovery system provided year round operational energy savings for make-up air handling unit with a total load reduction of 550 MBH (161 kw) wintertime and 194 MBH (16 tons) summertime.
  • Minimized shutdowns/impact on facility operations throughout four phases of construction through successful coordination with owner, architect and contractors during both design and construction phases of project.