ISO 13849-1 (performance levels)

ISO 13849-1 covers the design of safety-related parts of control systems and defines five performance levels, PL a through PL e, that express the ability of a safety function to perform under foreseeable conditions. The required performance level for a given safety function is derived from severity of injury, frequency of exposure, and possibility of avoidance. Robot safety functions such as emergency stop and safety-rated monitored stop are specified and validated against a performance level from this standard.

Standard
ISO 13849-1:2023, International Organization for Standardization (2023)