Fume-free Copper Chosen Over Plastics
Harvard School of Public Health auditorium before retrofit (left) and after (right). Detail of ceiling shows the sprinkler system (sprinkler head mounted horizontally). The housing also contains the conduit for the alarm system.Among the many advantages copper sprinker systems offer over plastic systems is the absence of noxious fumes during installation. And, although there exists a legal limitation to using plastic for fire sprinkler systems in buildings over three stories, eliminating fume problems was one reason why architect Douglas OKun chose copper for an expanded sprinkler system for the Harvard School of Public Health (HSPH) in Boston. Another was the design flexibility, ease of installation and ultilmately lower costs for doing an architecturally pleasing retrofit design. Although the $1.4-million system was to be installed at night, fumes generated in assembling a plastic system wouldn't’t have dispersed by the time employees arrived at the nine-story HS PH the following morning, according to Okun.
Installation was further complicated by five factors:
- The ceilings of the 30-year-old building were insulated with asbestos. Removing the insulation would have generated asbestos dust, a threat to daytime employees. Management decided to leave the asbestos undisturbed. Therefore, the sprinkler system could not be installed above or through the ceilings.
- Lighting levels needed to be raised in some spaces.
- The City of Boston requires sprinkler systems to be coupled to a complete fire alarm system.
- There could be no impediment at the top of the moveable walls to the installation of computer cables used to link the offices.
- The installation had to be aesthetically acceptable and compatible with the award-winning 150,000-square-foot HSPH building.
A typical HSPH passageway with retrofit copper sprinkler piping and conduit for the fire alarm cable mounted at the top of moveable walls. The painted copper sprinkler piping is the thicker piping farthest from the wall.Okun, based in Cambridge, Massachusetts, came up with two design approaches: one used copper sprinkler piping, conduit for the fire alarm cabling and a cable tray; and a second where more lighting was required in addition to the piping and conduit.
Initially, Okun considered covering the piping, conduit and cable tray with fiberglass covers. However, sharp bends in piping would have added to the cost of the covers. In the end, management decided to eliminate the covers as well as the cable tray for reasons of cost. The HSPH installation employs both ceiling and sidewall brass sprinkler heads in a creative, attractive and functional design.
Before the design was finalized, a short prototype section was load tested successfully. In addition, the Boston Fire Department had to approve the design. It should be noted that the low bid for installation – from Bond Brothers, Inc., of Everett – came in under the projected budget.
Detailing of the sprinkler system was done by Carlysle Engineering, Inc., Boston. According to Clayton A. Bemis of this firm, the copper piping was Type L, mostly of one-inch inside diameter, but ranging up to two-inch ID. The piping was supplied by Independent Pipe Company, Canton, Massachusetts.
Douglas Okun & Associates: 617/491-4600
Carlysle Engineering Inc. (Boston, Massachusetts): 617/522-6650
Bond Brothers, Inc. (Everett, Massachusetts): 617/387-3400
Independent Pipe Company (Canton, Massachusetts): 617/828-8500
Also in this Issue:
- Boosting Capacity of Copper
- Copper, Brass and Bronze Go Underground
- Existing Copper Saves Millions
- Copper says "Welcome" at Finnish Chancery
- Fume-free Copper Chosen Over Plastics
- Copper Helps Protect Precious PCs