SIL Threshold Records

SIL Threshold records store information about the numeric range for risk value for each Safety Integrity level, and are used when assessing SIL value using Risk Matrix or PHA. This topic provides an alphabetical list and description of the fields that exist for the SIL Thresholdfamily. The information in the table reflects the baseline state and behavior of these fields.

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Field	Data Type	Description	Behavior and Usage
Lower Boundary	Numeric	The lower boundary value of risk rank for the SIL value identified in the SIL level field.	You can enter a value manually.
Mitigated Risk Factor	Numeric	A number indicating the tolerable risk probability for an Instrumented Function.	You can enter a value greater than 0 and less than or equal to 1. The value in this field is divided by the Driving Risk Rank value in the Risk Matrix of the SIL Assessment to determine the Required Probability of Failure. If this field is blank, a default value of 1 will be used in the calculation.
SIL Level	Numeric	The Safety Integrity Level for which the unmitigated risk range is defined.	You can enter a value manually.
Upper Boundary	Numeric	The upper boundary value of risk rank for the SIL value identified in the SIL level field.	You can enter a value manually.