Designing Tall Buildings Post 9-11

As the construction of Freedom Tower proceeds at the site of the devastated World Trade Center in Lower Manhattan, it raises questions about the feasibility of rapid evacuation from a tall building in a disaster scenario. Over 95 years ago, similar questions were being considered on the construction project that produced the ill-fated ocean liner Titanic. In examining the Titanic project, there are a number of lessons from history that can be taken away and applied to the construction of today's skyscrapers.

Mark Kozak-Holland, author of the Lessons from History series of books as a few thoughts on the matter. In his latest book, "Avoiding Project Disaster: Titanic Lessons for IT Executives" (www.mmpubs.com), he describes the project that built the ocean liner TItanic and the business decisions that doomed the ship before it even left the docks.

"In the design phase of any project, whether a tall building, transportation vehicle, or even an IT system," Kozak-Holland states, "architects have to examine the requirements and determine safety and availability levels once delivered into operation. Likewise, Titanic's architects had to consider these levels of safety; they were faced with a number of technology choices over which safety features to incorporate into the ship. A transatlantic liner faces a number of hazards that may require rapid evacuation. Initially, Titanic's architects opted to go with the highest level of safety that incorporated the latest technologies including a double hull, bulkheads with electric doors, a front-end crumple zone, and triple-stacked lifeboats from 16 stations. This was expected when constructing the ultimate luxury liner and analogous to what you would expect today when purchasing a Lexus or Mercedes - high standards in both what it does and how it does it (functional and non-functional requirements)."

With tall buildings today, architects have safety technology choices too; for example, fire-resistant materials and sprinkler systems. At the Petronas Towers in Kuala Lumpur, the escape plan uses elevators to halve the evacuation time with smoke-proof waiting areas for those unable to escape the fire to wait for rescue by a service elevator. In the Taipei 101 Tower, each floor includes emergency escape corridors leading to fire-safe rooms, and there are outdoor balconies every eight floors allowing refuge. Specially reinforced fire or "bomb" elevators are exclusive to emergency crews and fire departments, allowing rapid access to fires and avoiding conflict with those trying to evacuate. Other safety technologies being developed include parachute-like devices for people to use to rescue themselves.

With Titanic's project, there was a twist in the story as the selected safety features were undermined by executive pressure from White Star's director Bruce Ismay who pushed for the ultimate passenger experience. Kozak-Holland's book shows how Ismay insisted, for example, in the need for a spacious 200-foot dining room/ballroom which cut straight across the bulkheads in the centre of the ship. Similarly, a desire to give a clear ocean vista to the first-class suites on the promenade/lifeboat deck was at odds with the triple-stacked lifeboats, towering 15 feet in the air. Titanic's overconfident architects conceded and, in the end, four bulkheads barely reached ten feet above the water line, and the 48 triple-stacked lifeboats were reduced to a single-stack of 16, far too few given the ship's passenger capacity. Similarly, the double hull that was supposed to extend the full height and wrap entirely around the ship was limited to just the hull bottom well below the water line, so as not to narrow the ship's interior width and to preserve valuable passenger space.

By the end of Titanic's construction phase, there was little acknowledgement that anything was seriously wrong with the design, even though the ship's non-functional requirements had been severely compromised. Titanic's architects and project team still believed that Titanic was practically unsinkable and could survive any situation because of the aggregate effect of safety features, her sheer size, the broad hull design, and the use of latest safety technologies. After all, no one had implemented this many safety features into a ship before. This fact was used actively as part of the marketing campaign, and expectations remained high. The lifeboats were viewed as an added safety feature, useful only if Titanic had to rescue another ship in distress.

Much has been written about the Freedom Tower's superior safety features like the 200 foot high concrete base; a concrete core with three foot thick concrete walls to protect life support systems like emergency stairs, elevators, fire suppression and ventilation systems; sensors and filters installed within the air supply system to detect chemical or biological agents; and a steel and titanium plate skin.

The sinking of Titanic was caused by compromises made during its design, construction, and testing phases to accommodate various business interests. These compromises reduced the effectiveness of safety systems and provided faulty operational data upon which to base management decisions. Kozak Holland concludes that "While no one could predict that the ship was going to run into ice, the compromises made during the build and launch of the ship almost guaranteed that any such collision was going to be a serious one."

The important lessons from history for today's Freedom Tower are:

• With a lengthy construction project of four years, do not allow overconfidence to develop based on the aggregated effect of all the safety features.

• Manage the expectation levels.

• Do not allow compromises of safety features to creep in.

After all, Titanic's construction project was also four years.