Exentec US Achieves First FM Approval for Large-Diameter Fume Exhaust Duct Systems Under Updated Safety Standard

Exentec US, Inc. has achieved a significant industry milestone by becoming the first U.S. manufacturer to receive FM Approval for large-diameter fume exhaust duct systems under the recently updated FM Approvals 4922 standard. This certification covers the company's Fab-Tech PermaShield™ duct systems across unrestricted diameters, sizes, and vertical riser heights, enabling facility owners and engineers to construct larger duct systems such as mains and submains with FM Approved products.

The updated FM 4922 standard, revised in March 2025, introduces enhanced fire safety and performance requirements specifically targeting duct systems above 60 inches in diameter. According to FM Approvals, a globally recognized certification organization, the revision establishes distinct Fire Propagation Index (FPI) classifications for both exterior and interior surfaces of ductwork, replacing the previous unified FPI requirement that applied across the entire system. This change is particularly relevant for single-wall constructions where the duct wall material itself must now comply with the new criteria.

"We are proud to be at the forefront of industry progress," said Jim Howard, General Manager of the Exhaust and Abatement team at Exentec. "This certification reflects our dedication to engineering excellence and our proactive approach to evolving safety standards. It also affirms our role as a trusted partner for clients seeking high-performance, compliant solutions."

The certification represents more than just regulatory compliance—it addresses growing industry concerns about property loss prevention and fire safety in industrial facilities. For clients in sectors such as semiconductors, life sciences, energy, and data centers, this development means access to duct systems that exceed the latest safety expectations while maintaining operational efficiency. The updated standard and Exentec's achievement underscore a shared commitment to advancing duct system reliability and performance across high-tech industries.

This development is particularly important as industrial facilities increasingly require larger duct systems to accommodate expanding operations and more complex ventilation needs. The certification provides facility owners with greater confidence in the safety and compliance of their exhaust systems, potentially reducing insurance costs and liability risks. More information about Exentec's products and services can be found at https://www.exentec.net.