A ladder is a vertical or inclined set
A ladder is a vertical or inclined set of rungs or steps. There are two types: rigid ladders that can be leaned against a vertical surface such as a wall, and rope ladders that are hung from the top. The vertical members of a rigid ladder are called stringers (US) or stiles (UK). Rigid ladders are usually portable, but some types are permanently fixed to buildings.
Rigid ladders are available in many forms, such as:
Step ladder:one kind is hinged in the middle to form an inverted V, with stays to keep the two halves at a fixed angle,which is called double sided step ladder. And the other kind is the vertical ladder, also called straight ladder. Another is household ladder ,it is like double sided step ladder.These Aluminum step ladder are the popular products of Zhongxin.
Extension ladder or Telescopic ladder, fixed ladder divided into two or more lengths for more convenient storage;
The full name of EN131 is "EN131 safety certification", which is a test for the safety of household ladder in European.
EN131 has different testing requirements for various ladders.
Vertical ladder, extension ladders, Push up or rope operated extending ladders, 2 plans,
Double ladder,Combination ladder 2 or 3 plans, Simple telescopic ladder
EN131-1/2/3 + Decree 96-333
Articulated ladder
EN131-1/2/3/4 + Decree 96-333
EN131 testing include: structural design, surface treatment, folding bolt testing, open range, ladder step pitch test, treadmill test, non-slip test, expansion testing, stability testing, load-bearing test, detection of toxic materials, stickers, and audit of corresponding Annex detection.
from:News|Zhongxin
