IEC 61508 ( functional safety of electrical/eletronic/programmable eletronic safety-related systems ) is an international, industry-independent functional safety. The seven-part standard spans IEC 61508-1 to IEC 61508-7. IEC 61508-3 is concerned with software development, verification, and validation. IEC 61508-3 highly recommends certified tools and translator for safety integrity levels (SILs) SIL 2 and higher; clause 7.4.4 provides "Requirements for support tools.