This paper considers the problem of safety control performance assessment for switched linear systems based on tensor residuals space approach.This study aims to clarify the effects of logical switching sequences between control systems and protection systems on process safety performance.Specifically,the tensor space approach is proposed to develop the model of switched systems,which can synthetically describe the logical relation between control systems and safety control systems.Furthermore,we develop the tensor residuals space based safety control performance assessment method which tells how variations in the logical switching sequences are reflected in fluctuations of the safety-important switched control systems performance in the worse case.The procedures based on tensor residuals space approach for computing the performance indices for the quantity are also provided.Finally,an illustrative example is given to show the usefulness of the proposed tensor residuals space approach for safety-important switched control systems performance assessment by comparing with the multiple model approach.