Under the new rules, any nonresidential skyscraper over 420 feet tall, or about 40 stories, must have a third stairwell and fireproofing capable of staying in place even if hit with 1,000 pounds per square foot of force, provisions that Mr. Frable and a real estate industry group, the Building Owners and Managers Association, want repealed. As an alternative, Mr. Frable is urging that skyscrapers include specially designed elevators that can reliably operate even during a fire.

Image The new 7 World Trade Center building has wider emergency stairwells and a fire-resistant area on each of its 52 floors. Credit... Fred R. Conrad/The New York Times

Separately, the building owners’ group has asked the organization to repeal a requirement that buildings taller than 75 feet apply glow-in-the-dark markings on stairwells as a backup if the lights go out. Such markings are credited with saving many lives on Sept. 11; they had been installed at the twin towers after the first terror attack there in 1993, even though the enhancement was not yet required by city code.

Only a small number of new towers would be subject to all three of the contested changes. Since 2000, about 10 nonresidential towers taller than 420 feet have been completed each year in the United States, according to Emporis, a German-based database of tall buildings, compared with about 750 such buildings currently standing nationwide.

The matter will go to a vote next week at a meeting of the code council in Minneapolis, where more than 1,000 building-code officials from around the nation will gather to adopt the 2009 version of the so-called model code, which serves as a template for 20,000 jurisdictions in all 50 states, including skyscraper cities like New York, Houston and Philadelphia. The council is a nonprofit association that was created in 1994 to try to develop a single national standard for building safety.

The contested provisions will now be reconsidered as part of a comprehensive review of the building code, which is conducted every three years. Most jurisdictions wait for that larger overhaul before revising their own codes; as a result, few cities have adopted the tougher skyscraper standards.

States and cities have the option of including or excluding any provision of the model code before making it binding, and many, including New York, make such modifications. Still, the code is important because it creates a base standard that most jurisdictions try to meet.