λ_device = λ_base * π_T * π_S * π_Q
SR-332 Issue 3 is not just a PDF—it is a methodology. Treat it with respect, pay for the license, and your reliability predictions will stand up to any audit or customer review. And if your contract allows, consider upgrading to Issue 4 for better component coverage. But for the millions of legacy systems still in production today, Issue 3 remains the undisputed king.
Telcordia SR-332 Issue 3 (2011) provides standardized methodologies for predicting the reliability and failure rates of commercial electronic equipment. It features three methods—parts count, lab test data, and field data—and offers enhanced modeling for device data, infant mortality, and operating conditions compared to older standards. Access the document and its revisions through Ericsson .
Once you have the PDF, here is how to apply it.
Go to (for issue 3). This is the heart of the document. It lists base failure rates (λ) in failures per billion hours (FITs) for:
Telcordia SR-332, formally titled Reliability Prediction Procedure for Electronic Equipment , is a handbook that provides a standardized method for calculating the steady-state failure rate of electronic components and systems. It was developed by Telcordia Technologies (formerly Bellcore and now part of Ericsson) to address shortcomings in older military standards like MIL-HDBK-217.