Work

The dimension of the PMHF functional safety metric of ISO 26262 standard

Year: 2026

Type: article

Abstract: The ISO 26262 functional safety metric PMHF, which characterizes the probabilistic properties of random hardware failures, is discussed. The PMHF metric is used to determine the automotive safety integrity level (ASIL). The disadvantages of determining this metric and the inaccuracy associated with the specified dimension [1/hour] are shown. According to the authors of the article, the PMHF metric (the average operational lifetime probability of a dangerous hardware failure per hour) is dimensionless. Reasonablearguments are given that the dimension of the PMHF metric cannot differ from the dimension of the averaged probabilities. The paper indicates the possible reason for the inaccuracy, and shows the correct way to calculate PMHF, which involves using not the operational lifetime (with a dimension of [hour]), but a dimensionless number of 1-hour time intervals within the device’s operational lifetime.

Source: Reliability: Theory & Applications

DOI: 10.66721/s1pfd068

Authors: Dmitriy Shevchenko, Victor Netes, Alexander Starovoitov

Institution: Moscow Technical University of Communication and Informatics

Language: English

Topic: Safety Systems Engineering in Autonomy

Subfield: Safety, Risk, Reliability and Quality

Field: Engineering

Domain: Physical Sciences

Open Access status: diamond

OpenAlex ID: W7165516487

FWCI:

Cites: 5

Cited by:

Related to: 10