It is preferred to open the aluminum ladder to see if it creaks when it is opened. It is definitely not a good aluminum ladder. When a good aluminum ladder is opened and closed, there is no sound. When the aluminum ladder is opened, can it be placed horizontally? , Such as shaking, check whether there are long or short feet, you can also check the materials and workmanship of the accessories, and finally determine the quality of the aluminum ladder interface as follows: a. The interface is fixed by rivets, you can see the processing status of the rivets , If there is looseness or the gap is too large, it is a non-conforming product; b. For welding with fixed interface, the weld bead must be fish scale-like sample as the standard product, and the weld bead must be full and the height and size should be uniform; c. 

The fixed interface The method is pressure riveting, you can see whether the connection between the stepping rod and the ladder beam is loose (not compressed), and the stepping flange should be uniform in size; in order to prevent the poor quality aluminum ladder from hurting us when checking the bearing capacity , We have to take a look at the maximum bearing capacity of the logo. When the bearing capacity is suitable for the weight, you can check it yourself. But it can't be increased at once. You need to add some weight test when you can bear it. The load in 12142-2007 can be divided into four files, namely 90KG, 100KG, 110KG, 135KG, and the safety load of qualified aluminum ladder should be more than 2.5 times of the mark.