The Council says it's too dangerous to have demolition and asbestos abatement going on at the same time.
City Council Speaker Christine Quinn says asbestos containment structures may also impede firefighters' access to areas of the building when this work is done simultaneously.
"Demolition and abatement of asbestos as a matter of course is not safer to be done together," Quinn said. "We've raised the standard today in way that makes building work much safer in the City of New York and hopefully fire fighting safer in the City of New York."
City firefighters Robert Beddia and Joseph Graffagnino died after they could not get water out of a broken standpipe inside the damaged Lower Manhattan office tower.