# ISO 13849-1/-2 · safety-related parts of control systems > ISO 13849 governs the safety-related parts of control systems: Part 1 is design, Part 2 is validation. Provael supplies adversarial fault cases the Part 2 validation plan can cite for a safety-related control function. Before anything else on this page: Provael computes no Performance Level — no PL, no PLr, no MTTFd, no diagnostic coverage, no CCF — and no SIL, and makes no functional-safety claim. A PL is determined from architecture and those quantities by the designer and confirmed by validation. An attack-success rate is none of those inputs and must never be presented as one. Regulation/standard: ISO 13849-1 / ISO 13849-2 Timing: A maintained international standard, not a dated obligation. It is the standard a machinery validation plan is written against. ## What it is - ISO 13849-1 specifies safety requirements and guidance for designing the safety-related parts of control systems, expressed as a required Performance Level (PLr) and an achieved PL from category, MTTFd, diagnostic coverage and common-cause failure. - ISO 13849-2 specifies the validation process: the plan, the analysis, and the tests that confirm the design meets its specified PL. - It is the standard a machinery integrator’s control-system file is written against, and it is named in the NVIDIA Halos inspection programme alongside IEC 61508 (see Primary references). - Machine-learned behaviour sits awkwardly in it: the framework was built for components whose failure modes are enumerable, and a policy driven off-task by a reworded instruction is not a failure mode the categories anticipate. ## Where a red-team result fits - **Part 2 — validation** - A validation plan lists the fault cases the safety-related control function must withstand. An adversarial episode that drove the policy out of its benign envelope is a fault case with a measured rate, an interval and a benign control — evidence the plan can cite, at the weight it deserves. - **What a PL is made of, and why an ASR is not one of them** - Performance Level comes from category, MTTFd, diagnostic coverage and common-cause failure. Provael measures none of those. A vendor offering to turn an attack-success rate into a PL is selling you a conversion that does not exist. ## What Provael maps to it - report.json#/by_attack — per-attack ASR with its 95% Wilson interval and the benign false-positive control, usable as enumerated fault cases in the validation plan. - report.mitigation.json — the pre/post result where a defence was applied, so a claimed risk reduction is measured rather than asserted. - attestation.json — the signed, dated bundle binding those numbers to the report digest. - dossier.oscal.json — OSCAL assessment-results for the assessor’s toolchain. - The one measured mitigation Provael has published: adversarial ASR 67.5% [52-80%] to 7.5% [3-20%] on the CPU fixture suite, benign false-positive rate unchanged at 0%. Credited, and substantially circular — the study leads with that judgement rather than burying it, and this page repeats it rather than quoting the improvement alone. - What this does NOT give you: a Performance Level, a PLr, an MTTFd, a diagnostic-coverage figure, a common-cause-failure rating, or a validation conclusion. Those are produced by your design and confirmed by your validation, and Provael is one input among them. ## Dates (verified 26 Jul 2026) - Status: In force, maintained (ISO 13849-1 and -2 are maintained standards rather than regulations with an application date.) - NVIDIA Halos AI Systems Inspection Lab announced: 22 June 2026 (The programme names ISO 13849 among the standards robot software is assessed against. Verified against the NVIDIA newsroom release on 1 August 2026.) ## Sources - ISO 13849-1:2023 — safety-related parts of control systems, Part 1 (ISO): https://www.iso.org/standard/73481.html - ISO 13849-2:2012 — validation, Part 2 (ISO): https://www.iso.org/standard/53640.html - NVIDIA announces Halos for Robotics, 22 June 2026 (NVIDIA newsroom): https://nvidianews.nvidia.com/news/nvidia-announces-halos-for-robotics-the-industrys-first-full-stack-safety-system-for-physical-ai - Provael — Halos / ANAB integrator card (docs): https://docs.provael.com/crosswalk/halos-integrator/ Canonical: https://www.provael.com/compliance/iso-13849 --- Provael · Prove it. Prevail. · Apache-2.0 · https://github.com/provael/provael Not legal advice; verify regulatory dates against the primary source.