ISO/AWI TS 21721
Guidance on the calculation of asymmetrical partitions/vertical membranes with respect to their fire resistance performance
Reference number
ISO/AWI TS 21721
Edition 1
Working draft
ISO/AWI TS 21721
A working group has prepared a draft.


This technical specification provides guidance on the calculation of the fire resistance performance of asymmetrical partitions and/or vertical membranes using existing fire test evidence. The fire resistance performance of asymmetrical partitions and /or vertical membranes is established on the basis of existing fire test evidence for asymmetrical partitions and /or vertical membranes to ISO 834-1 The asymmetric partitions are constructions that comprise of one, two, three or four layers of gypsum plaster boards which are installed against C-profile steel studs. The principles of the calculation methodology can be applied to other types of board materials used in partition systems and to other heating regimes.

General information

  •  : Under development
    : New project registered in TC/SC work programme [20.00]
  •  : 1
  • ISO/TC 92/SC 2
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