IEC Technical Specification 61508-3-1
IEC TS 61508-3-1:2016
Functional safety of electrical/electronic/programmable electronic safety-related systems - Part 3-1: Software requirements - Reuse of pre-existing software elements to implement all or part of a safety function
IEC TS 61508-3-1:2016(E) presents requirements by the application of which pre-existing software elements may be claimed to be proven-in-use for all or a part of safety function(s) of SIL1 or SIL2.
CHFÂ 40.-