Select an equation to calculate the dead time for a radiation counter system

Dead time is one of three critical parameters in the radiation measurement system that employs a GM counter tube. Dead time is determined using both accurate and approximation approaches. However, calculating the uncertainty of dead time using the exact method is challenging when instructing students. In this work, we present a method for selecting an equation from the approximation method to compute the dead time and its uncertainty, ensuring deviations are less than 5% when compared to the exact solution method.