At the forthcoming International Standards Organisation meetings in Seoul, Korea, IFC's Technical Director, Peter Jackman, has presented two Discussion Papers which hopefully will lead to new harmonised test methods removing confusion and filling a void in fire protection.
The first paper looks at the current conflict with the methods of test used for lift landing doors. Currently, there is an EN test 81-58 as well as an ISO test 3008, which is the basis of national tests, such as BS 476: Part 22: 1987. These two tests are very different in their method of test and their criteria of failure, unfortunately neither of them have a strong relationship with any fire scenario, particularly which reflects the special conditions that exist in lifts.
The Discussion Paper considers whether the criteria failure for a door to a lift, which is basically a sterile shaft, needs to be the same as for a door that is sub-dividing habitable parts of a building. The test should also recognise the much greater pressure differentials that will exist in a lift shaft due to the fact that one side is effectively a chimney and the other side is a compartment.
The second Discussion Paper considers the function and role of slab perimeter seals. The UK guidance in support of regulations has always required a seal to be installed between the end of the cast slab in a multi-storey building and the external façade. Recent changes in construction mean that it is now common for this to be a curtain wall which has a relatively low, if any, period of fire resistance. The function of this seal is always specified in terms of fire resistance, but an analysis of its performance will show it is very difficult to demonstrate fire resistance when fitted between and fire resisting and a non-fire resisting element. The Discussion Paper postulates that this seal is effectively a hot smoke seal and should be tested accordingly. Such a seal would operate in the pre-flashover, rather than a post-flashover phase of the fire. |