Petrochemical plants have been manufacturing phenol-formaldehyde resins for a long time, and over the years, many accidents have resulted from runaway reactions, sometimes with serious consequences. In this study, we used differential scanning calorimetry (DSC) and exacting measurements of pH conditions to investigate the basic characteristics of thermal polymerization. Careful laboratory examination of the processes, as well as a thorough survey of the accidents that have occurred in the past, led to the development of several reactivity accident prevention methods that can be employed to eliminate hazards associated with phenol-formaldehyde resin manufacture. Kinetic parameters, as well as prevention, are discussed in depth. Attention is drawn to the hazardous characteristics of various stages of manufacture, which should be of value in preventing these types of accidents in the future. This study is expected to be valuable to workers in chemical plants where phenol-formaldehyde resins are manufactured and processed. (C) 2017 Elsevier Ltd. All rights reserved.