A controller includes a calculator configured to receive process data necessary for controlling a plant and vital data indicating a state of a plant worker, the process data being received from a field device, the vital data being received from the plant worker, the calculator calculating first index data and second index data, the first index data indicating a gap between a current one of the process data and a previous one of the process data which is received when the plant is in a normal state, the second index data indicating a gap between a current one of the vital data and a previous one of the vital data which is received when the plant is in the normal state, and a determiner configured to determine health of the plant by using the first index data and the second index data which are calculated by the calculator.

Methods and computer program products for performing automatically determining when to shut down a fabrication tool, such as a semiconductor wafer fabrication tool, are provided herein. The methods include, for example, creating a measurement vector including process parameters of semiconductor wafers, creating a correlation matrix of correlations between measurements of parameters obtained of each wafer, creating autocorrelation matrixes including correlations between measurements of the parameter obtained for pairs of wafers; creating a combined matrix of correlation and autocorrelation matrixes, obtaining a T.sup.2 value from the measurement vector and combined matrix, and stopping a semiconductor wafer fabrication tool if the T.sup.2 value exceeds a critical value.

Aspects of the application relate to methods, a computer program and a process control device. According to one aspect, a computer-implemented method for determining a multivariate process chart is provided. The multivariate process chart is to be used to control a process to produce a chemical, pharmaceutical, biopharmaceutical and/or biological product. The multivariate process chart includes a first trajectory, an upper limit for the first trajectory and a lower limit for the first trajectory.