Peracetic acid (PAA) is potentially harmful because of its thermal hazards in industrial processes. Attention must be paid to the preparation, manufacturing, transportation, and storage because PAA may readily cause a thermal runaway reaction under various upset scenarios. PAA is classified an explosive substance in the governmental regulation in Taiwan. Here, 20 mass% of PAA was used to estimate the thermokinetic parameters by using differential scanning calorimetry. Heating rates employed were 1.0, 2.0, 4.0, and 8.0 °C min −1 . We compared the four heating rates of thermal safety assessment with regard to process safety parameters, such as exothermic initial temperature ( T 0 ) and heat of decomposition (Δ H d ). Finally, five kinetic analysis methods, along with differential isoconversional kinetic analysis, were used to estimate the apparent activation energy ( E a ). The experimental results could be used helpful during the manufacturing process, transportation, and storage as the process safety parameter considerations to forestall thermal damage from happening, and to reach zero-disaster purposes as the ultimate goals.