Regulation (EU) No 305/2011 lays down harmonized conditions for marketing construction products in the European Union. One of its consequences has been the introduction of the product standard EN 50575 and standard EN 130501-6, concerning power, control, and communication cables permanently installed in buildings to prevent the risk of a fire and its consequences. EN 13501-6 provides the reaction to fire classifications for cables, the test methods to be performed, the requirements to meet a specific reaction to fire, and additional classifications for smoke production, flaming droplets, and acidity. EN 60754-2 is the technical standard used to assess acidity, and it defines three classes: a1, a2, and a3 (the less performant), based on pH and conductivity measurements. Due to the release of hydrogen chloride during the combustion, acidity is the weak point of PVC cables, which are not yet capable of achieving the a1 or a2 classes required in specific locations according to a fire risk assessment. EN 13501-6 does not include EN 60754-1. Both EN 60754-1 and EN 60754-2 are common standards for determining halogen gas content, acidity, and conductivity, respectively. They involve the same type of tube furnace but with different heating regimes, final temperatures, and detection methods. EN 60754-2 must be performed at temperatures between 935 – 965 °C. The paper demonstrates that, when EN 60754-2 is carried out with the thermal profile of EN 60754-1 or at 500 °C in isothermal conditions, the evolution of hydrogen chloride changes significantly if potent acid scavengers are utilized in the PVC compounds. The reason lies behind the kinetic of hydrogen chloride release during the combustion of PVC compounds: the higher the temperature or faster the heat release, the quicker hydrogen chloride evolution and the lower the probability for the acid scavenger to trap it. That further highlights the "fragility" of EN 60754-2 as a tool for assessing the risks associated with the release of hydrogen chloride in case of fire