UL 9540A: thermal runaway fire propagation test method

UL 9540A is a test method producing data on thermal runaway and fire propagation in battery energy storage systems. It does not give a pass/fail certification; the data informs UL 9540 listings and fire code decisions.

Levels

Cell, module, unit and installation level testing proceed as needed based on results.

Standards scope summaries only. Test reports, certifications and transport classification are different outcomes; editions and market requirements change.