UL Numbering System Changes to Firestop System and Fire-Resistive Joint Systems
UL has announced a new numbering system for firestop systems and fire-resistive joint systems. Two categories are moving from a 4-digit System Number (C-AJ-2999) to a 5-digit System Number (Example, C-AJ-20000). It’s not a massive change or overhaul, but it’s important to understand to avoid confusion and ensure proper system selection and analysis – proving continued value of a Qualified Firestop Contractor.