07. Introduction to Evaluating Risks
Introduction To Evaluating Risks
ASIL (Automotive Safety Integrity Level)
The ISO 26262 standard defines a risk factor called ASIL - Automotive Safety Integrity Level. ASIL is a four point scale of ASIL A, ASIL B, ASIL C and ASIL D.
ASIL D represents a hazardous situation with the highest risk whereas ASIL A represents lower risk. ASIL is a key term in automotive functional safety. The video introduced the basic ideas behind how to calculate ASIL, but we will leave the details for the Hazard Analysis and Risk Assessment Lesson.
There is one more level of risk below ASIL A called QM. QM stands for quality managed. QM means that development according to accepted quality principles is sufficient to reduce risk. You will learn more about ASIL and QM in the lesson on hazard analysis and risk assessment.
Quiz
Let's measure probability of occurrence and severity on a scale from 1 to 4 with 4 representing highly probable and severe situations. Here are some guidelines for measuring probability of occurrence and severity:
Probability of occurrence:
1 - Vehicle jumpstart needed
2 - Driving in snow
3 - Driving at night with no street lamps
4 - Driving on the highway
Severity:
1 - No injury
2 - Light and moderate injury
3 - Severe and life threatening injuries with probable survival
4 - Life threatening injuries, survival uncertain, or fatal injury
Remember that:
** risk = probability of occurrence x severity**
RANK THE FOLLOWING HAZARDOUS SITUATIONS FROM LEAST RISKY TO MOST RISKY
A While driving on the highway, brakes fail at high-speed.
B Your vehicle requires a jumpstart. The power steering is not working but the vehicle is parked on the side of the
road and not moving.
C While driving in the snow in the city, anti-lock brakes fail while driving at low speed.
D While driving at night on a street with no street lamps, the car headlamps fail.
Evaluating Risk