I got an email this morning and creates my attention about the Crocs shoes…. The article came from OTIS…..

The story is begin like this…. A young girl stood on the Up escalator with a parent. On reaching the top of the escalator, the girls shoe was dragged into and underneath the comb plate causing significant damage to the shoe. The girl managed to remove her foot from the shoe and avoided injury just in time.

Then they start to investigate about the incidence. A pair of identical shoes were purchased. Tests were carried out to prove or disprove theories of how the shoes distorted under load off site. Tests were carried out on site to reconstruct the incident and ascertain the actual position of the shoe and the reactions on the escalator when the incident occurred.

The shoe construction, made from Croslite, a proprietary closed-cell resin that moulds to the contours of the feet, these shoes offer an exceptionally comfortable fit. Croslite is lightweight, waterproof, and slip and odour resistant. Croslite Resin is extremely soft and malleable which means that some parts of the shoe can get trapped between small gaps. Also, because the resin is “Non-slip” once trapped, it is difficult to release.
It was first assumed that the sole of the shoe had moulded into the step tread. The theory was disproved by placing the shoe on an escalator step and then loading 45KG on the toe area of the shoe.

The shoe was taken to the site where the incident occurred and held in different positions on the step. It was found that even with the toe of the shoe overhanging the step, it did not get trapped.

The shoe was then placed on the escalator with the soft toe touching the step riser. When the steps come into the transition area, the steps start to level out. Due to the very soft “Non-slip” construction of the shoe, it was found that if the toe of the shoe is pressed against the step riser, the shoe “Sticks” to the riser treads and is then trapped between the two steps. When trapped, the escalator only moves 2 steps before the shoe is dragged into the combplate.

The photograph on the left is the actual incident. The photograph on the right is the result of the investigation on site. Note the similarities.

CONCLUSIONS: Soft, rubbery shoes can be caught between escalator steps even if the gaps between the steps are in tolerance. If caught between steps, weight applied to the shoe can have detrimental effects. When stood on an escalator, shoes should be kept clear of step gaps and risers.

pssstt:… mama pon ada Croc shoes…. tapi bukan cam tu kan.. yang pesen tumit tinggi gitu…