Exentec US, Inc., a leading innovator in fume exhaust duct systems, has earned FM Approval for its Fab-Tech PermaShield™ duct systems under the newly revised FM Approvals 4922 standard. This certification makes Exentec the first U.S. manufacturer to receive FM Approval for duct systems exceeding 60 inches in diameter and sizes, demonstrating leadership in safety and engineering excellence. The approval covers unrestricted diameters, sizes, and vertical riser heights, allowing facility owners and engineers to construct larger duct systems such as mains and submains with FM Approved products.
FM Approvals, a globally recognized certification organization, updated its 4922 standard in March 2025 to strengthen fire safety and performance requirements for duct systems. The revision introduces distinct Fire Propagation Index (FPI) classifications for both the exterior and interior surfaces of ductwork, with new testing protocols specifically targeting systems above 60 inches in diameter. Previously, the standard applied a unified FPI requirement across the entire duct system; the update now mandates a separate FPI rating for the interior liner, ensuring that both external and internal components meet elevated safety thresholds. This change is particularly relevant for single-wall constructions, where the duct wall material itself must comply with the new criteria.
Jim Howard, General Manager of the Exhaust and Abatement team at Exentec, stated, "We are proud to be at the forefront of industry progress. 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 updated standard and Exentec's certification underscore a shared commitment to advancing duct system reliability and performance, enabling clients to benefit from products that meet or exceed the latest safety expectations.
Exentec is a global leader in mission-critical technologies and services for high-tech industries, with expertise spanning cleanroom environments, gas and chemical supply systems, modular solutions, and advanced HVAC. The company delivers integrated, energy-efficient solutions that enable innovation in sectors such as semiconductors, life sciences, energy, and data centers. Exentec process exhaust products are delivered by Exential, part of the Exentec family. For more information, visit www.exentec.net.
