Article 19.11(14)(a) – Fire protection for stairs
Article 19.11(14) lays down the following:
14. Internal stairs and lifts shall be encapsulated at all levels by walls according to (2). The following exceptions are permissible:
a) a staircase connecting only two decks does not need to be encapsulated if on one of the decks the staircase is enclosed according to (2).
(b) in a lounge, stairs need not be encapsulated if they are located entirely within the interior of this room, and
(aa) if this room extends over only two decks, or
(bb) if there is a pressurised sprinkler system according to Article 13.04 installed in this room on all decks, this room has a smoke extraction system according to (16) and the room has access on all decks to a stairwell.
Description of problem/question:
In accordance with the first sentence of Article 19.11(2), internal stairs and lifts must be encapsulated.
The term “encapsulated” is not defined in the RVIR [ES-TRIN] (e.g. the maximum permissible distances between the stairwell walls and the stairs or lift are not specified).
Also, according to (a), stairs do not need to be encapsulated where they are enclosed on one of the decks by walls according to (2).
What is the difference between “encapsulated” and “enclosed by walls”?
Examination of the question/answer:
The inspection body of Basel thinks the RVIR [ES-TRIN] should be clarified and therefore proposes the following change/addition to (14)(a):
(a) a staircase connecting only two decks does not need to be encapsulated if on one of the decks the room in which the stairs are located is enclosed by walls according to (2).
Do the other inspection bodies also take this view?
RV/G (08) 26 rev. 1, CH 2
The Chair summarised the Working Group’s conclusions as follows:
• In terms of its shape, the staircase described in Article 19.11(14)(a) is a semi-stairwell; the staircase must be enclosed by walls on at least one of the decks.
• The enclosure of a staircase is governed by the requirements applicable to the partitions between the two rooms connected by the staircase. In the case of a staircase between lounges, these are type-B partitions.
RV/G (09)m 1 point 4
CCNR Inspection Regulations Working Group RV/G, fire protection, stairs, stairwell