Ergonomic tools reduce arm and back injuries

UN/DICYT  A box folding machine, a labeler and a dispenser are some of the tools proposed by the Laboratory of Ergonomics to improve the position of employees of a perfume manufacturing plant.

What seems like a simple process such as packing lotion boxes is actually comprised of rapid hand, finger, elbow and shoulder movements as well as strong and constant back rotations.

This could cause injuries due to the speed and repetition of movements. For this reason the UNal Laboratory of Ergonomics and Human Factors took action against these factors.

According to Project Director Professor Ricardo Ruíz, the request to tackle these issues was made by a multinational perfume company which has received multiple reports of employee ailments.

“The foundation of our work was to verify postures, load strengths and repetitions. Although perfumes are light, the fact of assembling boxes and corrugated boxes to sustain bottles, glue labels and packaging are actually tasks that need to be performed carefully,” he said.

Ruíz says that the personnel in charge of this process can assemble up to eight boxes per minute. Another fact that was taken into consideration was use of stools by people who worked sitting down, as postures without leaning on a backrest may produce backaches.

“Stools were far from the conveyor belt that transported the perfumes, hindering the work position even more,” said Ruiz, also a member of the UNal Laboratory of Ergonomics.

After performing an observation field work and another participative field visit, the research team carried out a series of recommendations on how to reduce risks of injuries in upper extremities and back.

The group did not stop there and also designed and created tools to help in these processes, for example a folding machine which folds, seals and closes boxes. What a worker does in eight hand movements is reduced to two.

Another tool was a labeler, where they do not need to glue stickers turning the bottle, but they are placed on a conveyor and are glued at that moment.

In the act of leaning sideways to reach boxes the worker would not have to turn his/her body and impact his/her back but stand in front of a dispensing machine which is more practical having boxes at hand and placing them on the folding machine.

“We also designed stools more appropriate for optimal body positioning along with other features such as a foot rest and having the conveyor belt that carries the bottles nearer. Up to now the results have been satisfactory and there are far less employee injury reports,” said Ruíz.

Ruiz also highlighted the collaboration from the employees of the firm were they performed the tests and who from the beginning spoke freely about their situation and working forms.