What are the faults addressed in ISO/PAS 8800 standard? How is it different from ISO 26262?

Welcome back to all the safety engineers who want to explore the new ISO/PAS 8800:2024 standard along with us.

In our previous blog, we touched upon the scope of ISO/PAS 8800 standard and provided a "big picture" view of AI Safety life cycle as it is described in ISO/PAS 8800.

In this blog, we will try to understand the type of "faults" addressed in ISO/PAS 8800 standard and how is it different from ISO 26262 standard. Let us try to understand this by doing a comparison with ISO 26262 standard along with some examples.

As we know, ISO 26262 standard addresses hazards due to systematic and/or random hardware faults within safety-related E/E systems of the vehicle. ISO/PAS 8800 standard addresses hazards due to similar faults like ISO 26262 (systematic and/or random hardware) but additionally covers another fault i.e., output insufficiencies within safety-related AI systems of the vehicle.

"Performance insufficiency", "Functional insufficiency" and "Output insufficiency” are new terms which we do not have in ISO 26262.

• Performance insufficiency means an AI element does not perform well to meet the desired requirements, expectations etc.

  
  

• Functional insufficiency means insufficiency in the specification of AI element or performance insufficiency.

  
  

• Output insufficiency means wrong/insufficient output from an AI element used within a vehicle, resulting in a hazardous behaviour or inability to prevent/detect & mitigate a reasonably foreseeable indirect misuse (RFIM) or both.

Below table summarizes comparison between ISO 26262 and ISO/PAS 8800 standard with respect to goal, their applicability and the hazards that are addressed.

Topic	ISO 26262:2018	ISO/PAS 8800:2024
Goal	Absence of unreasonable risk due to hazards caused by malfunctioning behaviour of E/E systems	Absence of unreasonable risk due to AI errors caused by systematic faults, random hardware faults and output insufficiencies
Applicability	Applies to safety-related systems that includes one/more E/E systems and are installed in series production road vehicles	Applies to safety-related systems that includes one/more E/E systems that uses AI technology and are installed in series production road vehicles
Hazards	Addresses hazards caused by malfunctions of E/E safety-related systems	Addresses the hazardous behaviour due to output insufficiencies, systematic errors and random hardware errors of AI elements used within E/E safety-related systems

Below table summarizes some examples of output insufficiency, performance insufficiency, systematic fault and random hardware fault.

Faults	Examples
Output Insufficiency	An image recognition system using AI model may fail to identify and classify an animal/may classify an object incorrectly.
Performance Insufficiency	AI model not being trained well with sufficient dataset to predict/prevent collision of ego vehicle with Kangaroo
Systematic fault	AI model producing biased result due to systematic fault of using same data to train and evaluate the AI model
Random hardware fault	Bit flip in the safety critical memory due to ionizing radiation.