ISO 21448: STPA for SOTIF — From Control Structure to Triggering Conditions

Date
2027-07-09
Location
Online
Host
Zach L
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About this event

A live 30-minute expert session on STPA for SOTIF — From Control Structure to Triggering Conditions (ISO 21448 — Safety of the Intended Functionality). What We'll Cover: Where STPA fits in ISO 21448 hazard identification and why its control-loop view finds insufficiencies that FMEA-style analysis misses The method step by step: losses, hazards, control structure of the ADAS loop, unsafe control actions, and loss-scenario derivation How STPA outputs map to ISO 21448 triggering conditions and functional modifications, producing the UCA table and loss-scenario register Common mistakes: modeling only the software controller and omitting driver and environment, generic UCAs with no scenario, no closure into requirements The evidence auditors want: UCAs traced to SOTIF requirements, loss scenarios traced to validation tests, and rationale for out-of-scope items Related topics: stpa · system theoretic process analysis · unsafe control actions · loss scenarios · control structure · stpa sotif integration · hazard identification methods · adas control loop · uca table · scenario derivation stpa · stamp model · safety requirements derivation · stpa worked example · human controller model Critical Systems Analysis provides embedded functional safety consulting for ISO 21448 — Safety of the Intended Functionality. Learn more: https://criticalsystemsanalysis.com Partner with us: https://meetings.hubspot.com/benjamin-twombly/strategic-partnerships

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About Functional Safety Foundations

This online session delivers expert-led instruction on the regulatory landscape and implementation approach for Functional Safety Foundations.

The cross-sector fundamentals underlying every functional safety standard: risk as severity × likelihood, the safety function concept, integrity levels, the safety lifecycle, and the split between random and systematic failures.

What it regulates

Shared vocabulary and reasoning: hazard → risk → risk reduction allocation → safety requirement → verified implementation → maintained integrity in operation.

Who must comply

Everyone entering the field — the conceptual base of the entire catalog.

Key requirements of Functional Safety Foundations

  • Hazard and risk fundamentals
  • Safety function anatomy: sensor-logic-actuator with defined safe state
  • Integrity ladders (SIL/PL/ASIL/DAL) as risk-reduction currencies
  • Random vs systematic failure treatment
  • Lifecycle and management of functional safety incl. competence

Key concepts: Functional Safety Foundations

Risk reduction allocation
Distributing required risk reduction among mechanical design, safeguards, control functions and procedures.
Functional safety management
Planning, competence, documentation and assessment wrapped around technical work.
Random vs systematic
Hardware wear-out/chance failures quantified statistically versus design/process errors controlled by rigor.
Safe state
The defined condition a function drives the equipment to on demand or fault.

Frequently asked questions: Functional Safety Foundations

Why can't testing alone prove safety?

Rare-event targets (like 1e-7/h) are unverifiable by test duration, and systematic errors evade random testing — hence the standards' dual machinery of quantified hardware analysis plus process rigor and independent assessment.

Standard information based on the published text of Functional Safety Foundations. Event content is provided by the host. For authoritative guidance, consult the official standard body.