Page 207 - AGC_EN_iBook

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tHe OutSIDe FIRe StaIRS
By law, each compartment must have two emergency exits. As dis- cussed above, one is via the gallery.The other consists of outside stairs located within the double skin, linking the rst oor with
the ground oor. People on the second oor in the east wings can use the internal connecting staircase to get down to the rst oor, while those in the west wings can use the outside stairs available on two of the three terraces.
Outside re stairs are installed at the end of each of the four wings, i.e., a total of eight re stairs.They vary in length ( ve or six facade modules), depending on the (variable) height of the ground oor (car park).
hinged at one end, the stairs are an integral part of the walkways surrounding the building, i.e., in normal operating conditions they are in horizontal position, balanced by a counterweight held by a cable hanging from two roof-mounted pulleys. In the event of an evacuation, a trigger button is pressed, causing the stairs to be lowered.
When raised, the stairs remain almost out of sight, hidden behind the louvres.The height of their railings is the same height as
the windowsills and their white colour makes them blend in
with the latter.
Made of high-strength S690 steel, they are calculated in such
a way that they will not weigh too heavily on the louvre facade support structure.