This part of ISO 834 specifies the procedures to be followed for determining the fire resistance of loadbearing vertical separating elements when exposed to heating on one face. The application of this test to other untested forms of construction is acceptable when the construction complies with the direct field of application as given in this part of ISO 834 or when subjected to an extended application analysis in accordance with ISO/TR 12470. Since ISO/TR 12470 gives only general guidelines, specific extended application analyses are to be performed only by persons expert in fire-resistant constructions.