Accredited Fabricators

1. Confirm NSI Membership: Ensure your fabrication company is a current member of the Natural Stone Institute, as membership is a prerequisite for accreditation eligibility.

1. Review Accreditation Standards: Download and study the NSI Accredited Fabricator program requirements, including criteria for business practices, financial stability, quality control, safety, and craftsmanship.

1. Conduct an Internal Readiness Assessment: Evaluate your operations against NSI standards. Identify gaps in documentation, safety protocols, equipment maintenance records, and quality control procedures.

1. Prepare Required Documentation: Compile financial records demonstrating business stability, client references, quality control procedures, equipment inventories, safety programs, and any relevant certifications or training records.

1. Submit Your Application: Complete the NSI accreditation application and pay the application fee. NSI staff will review your submission for completeness before scheduling the audit.

1. Undergo the On-Site Third-Party Audit: An independent auditor will visit your facility to evaluate operations, equipment, safety practices, craftsmanship standards, and business practices against NSI criteria.

1. Address Any Findings: If the auditor identifies deficiencies, work to resolve them within the specified timeframe and provide evidence of corrective action to NSI.

1. Receive Accreditation and Promote Your Status: Upon approval, you will be listed in the NSI online registry of Accredited Fabricators and may use the official accreditation seal in your marketing materials.

The NSI Accredited Fabricator audit evaluates fabrication companies across several key operational and business dimensions. Business Practices and Financial Stability are assessed to confirm the company is a legitimate, financially sound operation capable of fulfilling contracts and standing behind its work. This includes review of business licenses, insurance coverage, and financial documentation.

Quality Control Systems are a central focus of the audit. Auditors examine whether the fabricator has documented procedures for inspecting incoming stone materials, monitoring production processes, and verifying finished products meet specifications. Equipment calibration records and production workflow documentation are reviewed.

Safety Protocols and Compliance are evaluated in the context of the fabrication environment, which involves heavy machinery, silica dust exposure, and hazardous materials. Auditors assess OSHA compliance, dust control measures, personal protective equipment (PPE) programs, and employee safety training records — an area of increasing importance given ongoing regulatory discussions around silica safety.

Craftsmanship and Technical Expertise are assessed through direct observation of the facility, finished work samples, and review of employee qualifications. The auditor evaluates whether the fabricator's team has the skills and equipment to produce work that meets industry standards for precision, finish quality, and material handling.

Client References are reviewed to verify the fabricator's track record of delivering quality work and maintaining professional business relationships. References from past commercial and residential clients provide independent validation of the fabricator's reputation.

The NSI Accredited Fabricator program is the most recognized third-party accreditation specifically for natural stone fabricators in North America. The Natural Stone Institute — formed through the 2015 merger of the Marble Institute of America (MIA) and the Building Stone Institute (BSI) — is the dominant trade association for the stone industry in the United States, giving its accreditation significant credibility among architects, designers, and commercial specifiers. The program is particularly well-regarded in the commercial construction and high-end residential sectors, where project owners and general contractors increasingly require verified supplier credentials.

Adoption of the accreditation is concentrated in North America, though NSI has international members and the program is available globally. The number of accredited fabricators is relatively modest compared to the total number of stone fabrication businesses in the market, which means accreditation remains a meaningful differentiator rather than a baseline expectation. Demand for the credential has been supported by growing specification requirements from architecture and design firms that use NSI resources and standards in their project documentation.

The program faces limited direct competition in the natural stone fabrication space specifically, though the International Surface Fabricators Association (ISFA) offers a competing accreditation for the broader surface fabrication market. Increasing regulatory attention to silica dust safety — particularly in California — is raising the bar for operational compliance and may drive more fabricators to seek formal accreditation as evidence of responsible practices. NSI's expanding sustainability initiatives, including the development of an industry-wide Environmental Product Declaration (EPD) and the Natural Stone Sustainability Standard, are also adding new dimensions of value to the accreditation ecosystem.

The Accredited Fabricator program was established around 2000 by the Marble Institute of America (MIA), one of the two predecessor organizations that would later form the Natural Stone Institute. The program was created in response to growing demand from architects, designers, and commercial project owners for a reliable way to identify qualified, reputable stone fabricators amid a fragmented and largely unregulated industry. By establishing a third-party audit process, MIA sought to elevate professionalism and quality standards across the fabrication sector.

A significant milestone came in 2015 when MIA merged with the Building Stone Institute (BSI) to form the Natural Stone Institute (NSI), consolidating the two leading North American stone trade associations under one roof. The Accredited Fabricator program was carried forward under the NSI banner and has continued to evolve alongside the organization's expanding focus on sustainability, silica safety advocacy, and technical education. NSI's development of the Natural Stone Sustainability Standard and industry-wide EPD in recent years reflects the organization's broader ambition to position natural stone as a credible, responsibly sourced material in the green building marketplace — further enhancing the relevance of its accreditation programs.