Engineering systems in manufacturing, industrial buildings: HVAC systems
Manufacturing and industrial facilities have some unusual engineering requirements, especially air handling, power needs, and fire/life safety systems. Air movement and air quality issues are discussed.
Jonathan Eisenberg, PE, Associate Manager, Rolf Jensen & Associates Inc., Boston
Brian P. Martin, PE, PDX Electrical Discipline Manager, CH2M Hill, Portland, Ore.
Peter Pobjoy, PE, LEED AP, Chief Design Officer, Southland Industries, Los Angeles
Peter Zak, PE, Principal, GRAEF USA, Milwaukee
CSE: What unusual requirements do HVAC systems for these facilities have that you wouldn’t encounter on other structures?
Zak: Selection of HVAC systems is based on ventilation requirements, process needs, and budgets.
Eisenberg: We often have a need for dedicated exhaust systems from more hazardous areas of a facility, which creates a need for additional shaft space in some cases. Also, in order to maintain the fire separation of the occupancy being ventilated, the dedicated exhaust ducts have to be enclosed in fire resistance rated construction. This is in lieu of installing fire dampers, which are prohibited in hazardous exhaust.
CSE: What unique solutions in HVAC systems or air movement have you specified recently? What “unusual” HVAC systems have you offered as an option to clients?
Pobjoy: Heat recovery is very important in buildings, especially where large quantities of outside air are used. We have recently used large enthalpy wheels for energy recovery in humid climates where we preconditioned 100% of the outside air entering the building both in the heating and cooling mode. In terms of air distribution, we have successfully used displacement ventilation by integrating the air supply into the building structure.
Eisenberg: We worked on a large pharmaceutical plant that needed to partially recirculate the ventilation for a flammable liquid processing area, due to FDA regulations. We determined this practice to be acceptable, with organic vapor detection and an interlock to go to 100% outside air in the event of a spill or vapor release.
Zak: The most common and cost effective have been air turnover units. These seem to work well in large open facilities and do not obstruct any other head operations such as cranes.