Last edit: 13/07/2023
Means of access for slopes between 20° and 45° (EN ISO 14122-1). Once definitions and references have been given, the standard provides a series of dimensional relationships concerning both the full dimension of the stair and the individual dimensions of the steps. Two levels can be connected by a single straight flight only for a difference in height H smaller than 4000 mm, otherwise multiple flights (with H< 3000 mm) are mandatory, interconnected by landings with length at least equal to the width of the step and never shorter than 800 mm.
With reference to the nomenclature, the following laws regulate the individual steps [14122-3:2016 – § 5.1-5-4]:
1. 600≤ g+2h ≤ 660 [mm].
2. 210 ≤ g ≤ 310 [mm].
3. r≥ 10 mm, valid for landings, too.
4. w≥ 800 mm for single pedestrian usage.
5. Minimum width increases to w≥ 1000 mm for multiple simultaneous pedestrian usage.
6. Minimum width decreases to w≥ 600 mm for single flights with height lower than 1500mm.
These values cannot change throughout the stair, with the exception of h1 (height of the first step) which may be reduced by up to 15% compared to the others.