US skyscraper evacuation plans to be released

A federal panel investigating the World Trade Centre collapse is poised to recommend new safety standards for all tall buildings in the US, including changes in construction and evacuation strategies.

The non-binding recommendations by the National Institute of Standards and Technology are the culmination of a three-year study of tall buildings meant to help occupants survive terrorist attacks or natural disasters.

The proposals are to be officially released tomorrow in New York and were first reported in today’s editions of The New York Times.

The panel recommends that evacuation plans be changed to provide faster escape routes for occupants of high floors, who investigators said tend to be isolated during emergencies.

The $16m (€13.2m) investigation also recommends that lifts be built with stronger shaft walls and equipped with wiring that won’t short-circuit if they get exposed to water – thereby providing an alternate escape route to stairways.

Standards for ensuring that steel is fireproof also should be stricter, the panel said, and sprinklers should have a backup supply of water.

Structural engineers estimated the proposed changes would increase development costs for most buildings by about 2 to 5%, the Times reported.

Limited evacuation capacity at the World Trade Centre could have led to 12,000 more deaths if the twin towers had been fully occupied during the attacks, the panel said. And if the towers had been full, it would have taken four hours to evacuate them – twice as long as either tower stood.

The International Building Code Council and the National Fire Protection Association, representing the insurance industry, will review the recommendations.