UL9540 ( Testing )

https://www.everexceed.com/difference-between-ul-9540-and-ul-9540a_n432 

UL 9540 is the essential safety standard for Energy Storage Systems (ESS), covering everything from batteries to inverters as a complete system for grid-tied or standalone power, ensuring safe construction, performance, and installation by looking at fire, electrical, and mechanical risks beyond just individual components. It ensures that integrated systems, like those used with solar, are safe for homes and businesses by testing how all parts work together, referencing other standards like UL 1973 (batteries) and UL 1741 (inverters) and often requiring specific UL 9540A testing for thermal runaway. 

UL9540A https://www.ul.com/services/ul-9540a-test-method

UL 9540A is a UL Solutions test method (not a certification) for evaluating the fire and explosion risks from thermal runaway in Battery Energy Storage Systems (BESS), using a tiered process (cell, module, unit, installation) to generate data for system design, safety, and code compliance, complementing the UL 9540 certification standard that lists the final system. It provides manufacturers crucial data on heat release, gas composition, and fire spread to ensure safer installations, often required for UL 9540 listing and regulatory approval (like NFPA 855).

UL1973 https://batterystandards.info/standard/ul-1973

UL 1973 is the safety standard from UL Solutions for rechargeable batteries used in stationary energy storage, light electric rail (LER), and auxiliary power for vehicles, focusing on fire safety, electrical hazards, and performance, ensuring they don't explode, catch fire, or leak under various conditions, and is crucial for integration into larger systems like those certified to UL 9540. 

NFPA855

https://www.nfpa.org/codes-and-standards/nfpa-855-standard-development/855 

NFPA 855 is the National Fire Protection Association's standard for the safe installation of stationary energy storage systems (ESS), covering design, construction, and operation to mitigate fire and life safety risks, with recent editions (like the 2026 version) adding requirements for new technologies, EV charging integration, and large-scale fire testing. It provides comprehensive criteria for fire protection, ventilation, and emergency response, applicable to various battery types and settings, and is enforced through codes like NFPA 1 and the IFC. 

NFPA68 

https://www.nfpa.org/codes-and-standards/nfpa-68-standard-development/68

NFPA 68 is the National Fire Protection Association (NFPA) standard that provides guidelines for explosion protection by deflagration venting, a passive safety system designed to release combustion gases and pressure from an enclosed space during a deflagration (rapid burning) to prevent structural failure and protect people. It covers the design, location, installation, maintenance, and use of vent systems for equipment like dust collectors, pipes, and ducts, ensuring vents are sized correctly and direct hazards safely away from personnel. The latest edition (2023) updates technology, combines hazard distance requirements, and adds guidance for gases like hydrogen. 

NFPA69

https://www.nfpa.org/codes-and-standards/nfpa-69-standard-development/69 

NFPA 69, the "Standard on Explosion Prevention Systems," provides critical requirements for designing, installing, and operating systems that stop explosions from forming or spreading in equipment containing flammable dusts, gases, vapors, or mists, covering methods like inerting, suppression, isolation, and oxidant/fuel control for industries like woodworking, grain processing, and machining to protect pipes, ductwork, and vessels.