Solutions of organic diacids in nitric acid are processed in the manufacture of adipic acid, a Nylon intermediate. In these solutions, a secondary reaction can be initiated where the controlling reactants are the nitrogen oxides produced by the reaction itself. As the reaction takes place in a sealed vessel, the nitrogen oxides produced pressurize the vessel causing the reaction to speed up. Depending on the proportions of nitric acid, organic diacids and water, the reaction can be more or less violent, i.e. slow reaction, deflagration or detonation. The slow reaction was investigated by considering two separate contributions: the exotherm, measured by DSC/DTA experiments, and the non-condensable gas production, measured in sealed Dewar flasks and autoclave experiments. The deflagrating behaviour of the reaction was investigated using autoclave experiments in which the rate of pressure increase is allowed to reach around 10 000 bar s −1. The sensitivity to detonation was investigated using a detonation test tube. The critical diameter, detonation velocity and curvature of the shock front were measured as a function of the solution composition. Following the DIERS recommendations, a vent-sizing method is proposed for rupture discs to prevent explosion of pipes containing nitric acid solutions of organic diacids. This experimental information helps in understanding the explosion hazard in adipic acid manufacture and provides a valuable basis for recommendations for safe handling of nitric acid solutions of organic diacids.