Reproducibility of the box test according to EN 61482-1-2 and influences on the test energy parameters

The box test according to IEC/EN 61482-1-2 is one of the internationally harmonized test methods for textile material and protective clothing for arc flash protection. The standard is now under maintenance in an IEC TC 78 Project Team. In the frame of this work, among others, a round-robin-test was made for analyzing the reproducibility and repeatability of the test method. In the paper the results of this work are presented. Furthermore, the paper reports on laboratory measurements aimed to consider the influences of variations of the box test parameters on the electric and thermal arc energy. Main focus is the time and current dependency of the electric arc energy as well as the direct exposure incident energy. On this base the relationship between electric arc energy and incident energy is derived, allowing conclusions on PPE test energy levels in case of deviations from the standard conditions (class 1 and 2) as well as conclusions on arc exposures at real work places for risk assessment and PPE selection.