Ergonomics

Ergonomics mean adjusting the work to the human being. When adjusting the work to the human being, it is important to consider muscles and joints.

How do I use myself best?

Human beings are fantastic constructions and the way our minds and bodies work is unexcelled by any technological wonder.

Human beings are undoubtedly created to perform physical and intellectual work. By using our brains - to think about the way we tackle physical work - we give ourselves a good change of keeping healthy all our lives.

However, this is what matters when talking about quality of life
- "a healthy mind in a healthy body"

 

 

WHAT DOES ERGONOMICS MEAN?

Ergonomics mean adjusting the work to the human being. When adjusting the work to the human being - the employees of the company - it is important to consider muscles and joints.

Where the muscles are concerned, a distinction is made between static and dynamic work.

  • With static work, the muscles are under constant strain and become tired quickly. Over longer periods, such strains often lead to disorders in both muscles and sinews.
  • With dynamic work, the muscles are alternately stretched and relaxed; the joints move the whole time. This type of work helps the circulation since the muscles receive a constant supply of fresh blood containing oxygen and nourishment

When considering the joints, these should always be allowed to work in and around their “intermediate position” – their natural resting position. This helps to minimise the load on cartilage in the joints and helps to prevent osteoarthritis.
The shoulder joint works best when the upper part of the arm is kept vertically down. When the load is on the heavy side, the elbows work best at an angle of about 120°. For lighter loads, 90° is suitable.

The wrist performs best when held straight out as an extension of the forearm or bent backward with the thumbs pointing diagonally inwards/upwards.

Finger joints work best when slightly bent.

It is best for the legs to alternate between standing, walking and sitting.

The back works best and is burdened least in standing or upright position; in this position the spine assumes its natural curvature.

IMPORTANT WHEN ARRANGING WORKSTATIONS

Examples of inappropriate movements when lifting and transporting loads manually:

  • Lifting too quickly or when leaning to one side
  • Starting to lift with a jerk or stopping suddenly while lifting
  • Twisting the body/neck, bending forwards or sideways. The strain increases with the extent of bending and twisting, and with the length of time the position is held
  • Lifting the arms, especially if the hands are raised above shoulder height
  • Lifting low loads; the whole body has to be lifted in addition to the load
  • Lifting from the side or with one hand; the pressure on the spine becomes about twice as much as when lifting with two hands in front of the body

There are different ways of making work less physically demanding, for example:

  • By ensuring that the equipment used is designed to suit the work and the user. If the lifting does not involve great power, it is often advantageous for the user to use the equipment in standing and sitting positions
  • By keeping the distance to the object being lifted as short as possible during the whole lifting operation (from the point of gripping to the point of releasing)
  • By making the working height adjustable so that a good working position is possible, i.e. the load must be kept close to the body between mid-thigh and elbows so that twisting or bending the spine is not necessary


APPLICATION SITUATION

Transport of pallets and goods
When choosing a pallet truck it is important

  • that the starting power concerning both pulling and pushing is as low as possible
  • that the handle has an ergonomically correct design
  • that only a little power is necessary for the pump function on a manual truck

The Panther pallet truck has an ergonomically designed handle.

The hoop skates on the forks are perfectly designed to ensure an easy fork insertion and withdrawal in/out of closed pallets.

Working at machines & assemble lines
When working at machines and assembly lines, objects are taken from a pallet placed on the one side of the user, prepared and delivered to the opposite side or taken from assembly lines and put on pallets.

Without equipment this might imply lifting both from and to very low heights - meaning strain. A Thork Lift or a stacker could be a good solution. When choosing, it is from an ergonomic view important

  • that the user can move freely on the floor in order to avoid twisting of his back and neck
  • that the working height is correct all the time in order to avoid bending of the back - when working in too low levels - and to avoid lifting of shoulders and arms - when working in too high levels
  • that the distance to the object is as short as possible

If the work implies large and heavy objects, the best way to perform the work is in a standing position. Here a Thork Lift is the perfect solution.

If the work implies small and light objects and can be performed in a sitting position, a stacker is advantageousllets.

 

Transporting and stacking

- in restricted areas. Loading and unloading of vans.

Without equipment this work would mean large strain when lifting low and high in awkward positions. A stacker is here the perfect choice and from an ergonomic point of view it is important

  • that minimum power is necessary for the pump function on a manual  truck, meaning a minimum strain of shoulders and arms
  • that the stacker is easy to manoeuvre, meaning a minimum strain of arms and back
  • that the handle has the correct thickness and angles according to ergonomic principles
  • that the stacker can be operated fully by the handle. Contrary to e.g. lifting/lowering by a foot pedal, meaning that the user has to stand on one leg
  • that the user has a good view over the load during the operation and  at the same time has a correct working position

Handling of drums
- in order to fill liquids on other containers.

If this kind of work has to be performed manually, two persons are needed, meaning a large strain of their backs and arms.

From an ergonomic point of view it is important 

  • that lifting and handling of drums are not performed manually, because the strain of back and shoulders is too large

Interthor offers a drum turner for all stackers, being able to lift, transport and turn the drum 360º and to grip from both horizontal and vertical position. It is available in both a manual and an electrical version with clamp fittings for both 200 l steel drums and for the most standard plastic drums - the drum turner will without doubt save many backs.

For handling horizontal drums, drum forks are offered. With drum forks different types of drums, reels and barrels can be handled.

Filling and emptying boxes
- of objects into/out of boxes, large plastic containers, crates etc.

From an ergonomic point of view it is a claim that correct lifting methods can be used during working, no matter whether the work concerns heavy or light object. However, lifting the container, so that the top edge is in a good working height, is not enough. It is necessary that the angles allow the user to reach the objects without bending his back. 

It is important that

  • the back can work in its "intermediate position"
  • the distance to the objects is as short as possible considering back and shoulders.

The choice could be a Logitilt or a Rotator. These products make it possible to tilt a container or box into a good working position of the back by changing the tilt degree when filling/emptying the box. In this way the user gets the least possible distance to the objects and the least possible strain of his back and shoulders.

With a Logitilt a load can be tilted up to 90º. The working height can be varied from 750 to 950 mm, which makes both standing and sitting work possible. The handle can be turned to the side, giving free access to the box opening.

A Rotator can be set to turn up to 180º to each side.

 

EU FOCUS ON ERGONOMICS
Survey of the working environment
In 1996 the European Foundation for the Improvement of Living and Working Conditions, Dublin, conducted a survey of the working environment. The survey involved interviews with a representative part of the working population consisting of about 1000 employees in each of the member countries of the EU, i.e. an approximate total of 15,800 persons were interviewed. 30% of the respondents named back pains as their most frequent cause for complaint. This is a problem that ought to be taken seriously. 

Work assessment according to EU Directive 89/391/EEC of 12 June 1989
In order to gain an overview of the working environment in the company, it is a good idea to conduct a workplace assessment. Within the EU this is a requirement, stipulated in EU Directive 89/391/EEC of 12 June 1989. A workplace assessment is conducted through co-operation between the employer, employees and safety organisation of the company and is a good starting point for laying down priorities and a plan of action for improving the working environment. 

In particular, the purpose of a workplace assessment is to prevent or reduce physical stress at work, and to create a well-arranged and flexible workplace with a rational organisation of the work. 

The legislation concerning working environment within the EU lays down that manual handling involving safety and health risks must be avoided. If this is not possible, effective measures must be adopted to eliminate the risks. Suitable equipment must be used when possible or appropriate, and always when the manual handling involves health risks.