The Greenest Skyscraper Complex : WTC -BREATHING EASIER

During construction, the complex is requiring its contractors to use only ultra-low sulfur diesel fuels—a "clean diesel" that reduces nitrogen oxide and particulate emissions and is considered one of the cleanest (comparatively speaking) fuels available. This implementation is so effective that New York City and State now require that non-road construction equipment used on public construction projects by public agencies use ULSD. In addition, all construction vehicles are equipped with extra particulate filters to further reduce their impact. Finally, the materials used in the complex cannot include any Volatile Organic Compounds (VOC)—a variety of chemicals that leach from building materials in gaseous form with both short- and long-term health effects.

After construction is complete, Del Valle states that, to further improve indoor air quality, they're going to watch it like a cybernetic hawk:

"CO2 monitors control ventilation and make the building healthier and improve indoor air quality. If the CO2 sensor sends a signal to the air handler software, telling it you need more fresh air in a certain space because there's more CO2 than there should be, it automatically increases the fresh air mix coming into that space. We have over 3,000 points of monitoring."

In addition, the WTC will improve the air of the greater Manhattan Financial District by reducing the amount of vehicular traffic in the area by providing ample public transportation access and extensive facilities for bicycle commuters.

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