Adiabatic describes a system or measurement mode without any heat exchange with the surroundings. This mode can be realized using a calorimeter device according to the method of accelerating rate calorimetry (ARC®). The main purpose of such a device is to study Worst-Case ScenarioRelated to a chemical reactor, a worst-case scenario is the situation where temperature and/or pressure production caused by the reaction runs out of control.worst-case scenarios and Thermal runawayA thermal runaway is the situation where a chemical reactor is out of control with respect to temperature and/or pressure production caused by the chemical reaction itself. Simulation of a thermal runaway is usually carried out using a calorimeter device according to accelerated rate calorimetry (ARC).thermal runaway reactions. A short description of the adiabatic mode is “no heat in – no heat out”.