A new version of the widely used code promulgated by the U.S. Green Building Council – LEED v.4 – is drawing fire from the American Chemistry Council. The new version of the code “has strayed from its original mission of promoting energy efficiency and environmental performance,” according to the ACC’s Debra Phillips, “by adding new provisions that discourage the use of certain products and materials without a scientific basis for doing so.”

The LEED system awards points to a building design according to certain criteria, such as energy efficiency, land use, stromwater management, and bicycle racks. ACC is concerned about a new materials and resources category, allowing building owners to win credits for how raw materials are extracted and potential health hazards in product ingredients.

The product-ingredients credit seeks more transparency from suppliers and relies on relatively unproven standards, such as the health product declaration. An Architectural Record story reported ACC challenged this credit because it demands transparency and targets certain substances that are in widespread use, such as brominated flame-retardants.

According to Phillips, however, the new credits in LEED v.4 that encourage the avoidance of products containing certain chemicals “were developed without input from experts in toxicology or chemical safety,” and “are based on flawed opinions, and without regard to the availability, safety or effectiveness of alternatives.”

Phillips argues that many of the products that LEED v.4 seeks to eliminate actually enable the very efficiency enhancements, environmental performance and sustainability improvements that LEED purports to promote. The revised code is due to go into effect in November, although the previous version can be used until June 2015.