The Natural Stone Council (NSC) and NSF International have developed the first sustainability assessment standard for stone – 'NSC 373 Sustainability Assessment for Natural Dimension Stone.' The standard defines criteria for the sustainable development aspects of dimensional stone production while harmonizing environmental requirements for stone quarrying and production.

NSC utilized NSF International’s technical expertise as an American National Standards Institute (ANSI)-accredited standards developer to help create the consensus-based standard. When finalized as an ANSI standard it is expected to assist in acceptance of NSC 373 by trade and sustainability stakeholders.  NSF helped NSC through the consensus process by gathering and managing a joint committee comprised of key stakeholders to define and agree on criteria for the standard. The committee included stone industry trade associations, quarry and processing companies, NGOs, architects, and government, environmental advocacy, academia, green building and design groups.

Transparent, credible standards along with independent third-party certification are important to meet the demands of members of the construction industry seeking more sustainable stone products. This includes government agencies (local, state and federal) and others seeking to comply with U.S. Executive Order 13514, which aims for 95 percent of government contracts to include products and services with sustainable attributes.

Certification to NSC 373 by quarries and processors is the first step in the product certification process for natural dimension stone. Full certification for stone products will be achieved through a combination of NSC 373 certification for quarries and processors along with chain of custody (NSC COC) compliance for the rest of the distribution chain.  The NSC COC program is currently in development and near completion.  

“As products with sustainability claims continue to enter the marketplace, independent, third-party certification of products to consensus-based standards can help architects and specifiers make educated decisions about product selection,” said Duke Pointer, executive director of the Natural Stone Council. “NSC 373 provides a needed standard of excellence in sustainability for the natural stone industry and will serve as the first step of the developing NSC Chain of Custody program.  NSC 373 with NSC COC will define and help promote more sustainable products within our industry.”

“NSF International helped NSC establish a stone standard which includes well-defined environmental, ecological, social responsibility and human health metrics through a multi-stakeholder, science based approach," said Tom Bruursema, general manager of NSF International’s Sustainability Division. “The criteria in this standard will help quarry operators and stone fabricators assess their internal practices, drive efficiencies and attain preferred status in their markets as the building industry continues to value sustainable products and practices.”

The NSC 373 standard is leading the transition to verified, more sustainably extracted and processed natural dimension stone. This allows the natural stone industry to compete on a level playing field with other industries that already have sustainability standards and enables quarries and primary processing plants to demonstrate commitment to applying more sustainable approaches to development and corporate operations.

How NSC 373 Certification Works

NSF International provides certification to the new NSC standard through the NSF Sustainability Division. NSF Sustainability will evaluate natural stone quarrying and fabrication operations in several key impact categories, including water, transportation, site management, land reclamation and adaptive reuse, and management of excess process materials and waste.

Certification to NSC 373 is based on point totals to achieve Bronze, Silver, Gold or Platinum level certification. Monitoring and periodic re-evaluation is required to maintain certification.

For additional information on NSF’s sustainability services, contact Dennis Gillan at (734) 476-2543 or sustainability@nsf.org.