This protocol contains the safety regulations for using appliances and pipe systems under increased pressure (> 0.5 bar overpressure). These specific safety regulations result from the European guideline on pressure equipment. (PED). In the PED a subdivision is made between: Equipment for academic research and not for academic research (the only set-ups that may be counted as academic research are the ones with which that type of research is performed).
We speak of a vacuum when pressures are lower than the surrounding pressure (negative pressure). This protocol describes the measures taken to minimize the risks with respect to overheating, overpressure and backfiltering.