In order to solve for the factor, temperature readings are taken every 0.25 hours (or sooner - every minute) of the cook and relative rate constants kr determined. The kr is plotted versus time. The area under the curve is equivalent to the H factor (Figure slide 11). Sample calculations for the determination of the H factor can be found in slide 12. The accuracy of this method can be seen in slide 13 for the determination of endpoint at 3 different temperatures. It needs to be stressed that this equation only estimates the effects of time and temperature and assumes constant effective alkali, sulfidity, liquor/wood, wood species, etc. All these factors and more can change the rate,