The final report from the most detailed examination of a building failure ever conducted was released at a hearing this week of the House Science Committee on the NIST investigation at which Jeffrey testified. Featured in the report are 30 recommendations designed to improve the safety of tall buildings, their occupants and first responders. It is available online.
Jeffrey said that NIST believes its recommendations are realistic, appropriate and achievable within a reasonable period of time. However, he cautioned that improvements would only be realized if they are acted upon by the appropriate organizations. To facilitate this effort, NIST to date has:
• identified specific codes, standards and practices affected by each of the 30 recommendations in the final WTC towers report;
• reached out to the organizations responsible for making changes to expedite consideration of and action on the recommendations (for example, NIST held a major technical conference on the recommendations in September 2005 attended by over 200 people, including representatives from all major standards and codes development organizations); and
• awarded a contract to the non-profit National Institute of Building Sciences to turn many of the recommendations into code language suitable for submission of code change proposals to the two national model code developers, the National Fire Protection Association and the International Code Council.
The NIST recommendations are contained within 43 separate reports (totaling some 10,000 pages) that cover:
• specific improvements to building standards, codes and practices;
• changes to, or the establishment of, evacuation and emergency response procedures; and
• research and other appropriate actions needed to help prevent future building failures.
Based on nearly 500 comments received during the six-week public review period following the release of the draft WTC towers report on June 23, 2005, the reports — including some of the recommendations — were amended and clarified. Both the complete set of comments and the full version of the final recommendations are available online. The recommendations are divided into eight groups:
• Increased Structural Integrity: The standards for estimating the load effects of potential hazards (e.g., progressive collapse, wind) and the design of structural systems to mitigate the effects of those hazards should be improved to enhance structural integrity.
• Enhanced Fire Resistance of Structures: The procedures and practices used to ensure the fire resistance of structures should be enhanced by improving the technical basis for construction classifications and fire resistance ratings; improving the technical basis for standard fire resistance testing methods; using the “structural frame” approach to fire resistance ratings; and developing in-service performance requirements and conformance criteria for spray-applied fire resistive materials (SFRMs, commonly referred to as “fireproofing”).
• New Methods for Fire Resistance Design of Structures: The procedures and practices used in the design of structures for fire resistance should be enhanced by requiring an objective that uncontrolled fires result in burnout without partial or global (total) collapse. Performance-based methods are an alternative to prescriptive design methods. This effort should include: (1) the development and evaluation of new fire resistive coating materials and technologies, and (2) the evaluation of the fire performance of conventional and high-performance structural materials (such as fire-resistant steels and concretes). Technical and standards barriers to the introduction of new materials and technologies should be eliminated.
• Active Fire Protection: Active fire protection systems (i.e., sprinklers, standpipes/hoses, fire alarms and smoke management systems) should be enhanced through improvements to design, performance, reliability and redundancy of such systems.
• Improved Building Evacuation: The process of evacuating a building should be improved to include system designs that facilitate safe and rapid egress; methods for ensuring clear and timely emergency communications to occupants; better occupant preparedness for evacuation during emergencies; and incorporation of appropriate egress technologies.
• Improved Emergency Response: Technologies and procedures for emergency response should be improved to enable better access to buildings, response operations, emergency communications, and command and control in large-scale emergencies.
• Improved Procedures and Practices: The procedures and practices used in the design, construction, maintenance and operation of buildings should be improved to include encouraging code compliance by non-governmental and quasi-governmental entities; adoption and application of egress and sprinkler requirements in codes for existing buildings; and retention and availability of building documents over the life of a building.
• Education and Training: The professional skills of building and fire safety professionals should be upgraded through a national education and training effort for fire protection engineers, structural engineers and architects. The skills of building regulatory and fire service personnel also should be upgraded to provide sufficient understanding of what is needed to conduct the review, inspection and approval tasks for which they are responsible.
