Key Indicator Method for Activities involving Pulling, Pushing

The assessment is basically conducted for individual activities and relates to one working day. If load weights and/or postures change within an individual activity average values must be formed. If a number of manual handling tasks with substantially different load manipulations arise within the overall activity, they must be estimated and documented separately.

The following 3 steps are necessary in the assessment:
1. Determination of the time rating points,
2. Determination of the rating points for the key indicators and
3. Evaluation.

In the determination of the rating points it is basically permitted to form intermediate steps (interpolation). A frequency of 40 produces the time rating point 3, for example.

The Key Indicator Method worksheet for activities involving Pulling, Pushing can be downloaded here:

Interactive KIM-Worksheet for activities involving Pulling, Pushing (pdf-File, 653 kB)
This interactive worksheet allows to fill the form on a computer and automatically calculates the activity-related risk score. The result may be saved on the computer.

Further useful documents related to this method:

Printable KIM-Worksheet for activities involving Pulling, Pushing (pdf-File, 225 kB)
This worksheet is for use without a computer for paper-pencil assessment.

Short lesson with examples and Answers to frequently asked Questions (pdf-File, 2 MB)
This short lesson provides useful information for using KIM in practice, gives examples for assessment and gives answeres to frequently asked questions.

Caution!
This procedure serves for an orienting assessment of working conditions with the pulling and pushing of loads. Nevertheless good knowledge of the manual handling task being assessed is absolutely essential when determining the time rating, the rating points for mass, positioning accuracy, speed, posture and working conditions. If this knowledge is not present no assessment may be made. Rough estimates or suppositions lead to incorrect results.

1st step: Determination of the Time Rating Points

The time rating points are determined, with reference to the table, separately for pulling and pushing over short distances with frequent stopping and pulling and pushing over longer distances:

• For pulling and pushing over short distances with frequent stopping the frequency is taken as the basis.
  
• For pulling and pushing over longer distances the total distance is taken as the basis.
  

The limit value for the individual distance of 5 metres should be regarded as a rough aid. In cases of doubt a decision should be taken according to which criterion arises more frequently: start-up and braking or extended pulling.

2nd step: Determination of Rating Points of Mass, Positioning Accuracy, Posture and Working conditions

2.1 Mass to be moved

The determination is conducted with reference to the table, taking account of the mass to be moved (weight of means of transport plus load) and the nature of the means of transport (industrial truck, aid). Very often drawbar-less trolleys with rollers are used. A distinction is drawn here between (steerable) steering rollers and (non-steerable) fixed rollers.
If different loads are handled in the course of the individual activity to be assessed, an average value may be formed. For comparison purposes peak load values may also be used. Then the lower frequency of these peaks must be taken as a basis and on no account the overall frequency.

2.2 Positioning Accuracy and Speed of Motion

The determination is conducted with reference to the table. The speed "fast" is equivalent to normal walking. If in special cases there are clearly faster speeds, the table can be extended as appropriate and a 4 or 8 can be given. Interpolations are permissible.

2.3 Posture

The posture rating points are determined with reference to the pictograms in the table. The characteristic postures during the handling of loads must be used for the individual activity. If different postures are adopted, an average value may be formed from the posture rating points for the manual handling task being assessed.

2.4 Working Conditions

To determine the rating points of the working conditions, the working conditions that predominate most of the time must be used. Occasional discomfort which has not safety significance will not be taken into account.

3rd step: Evaluation

Each task is evaluated with reference to an activity-related risk score (calculation by addition of rating points for the key indicators and multiplication by the time rating points). If women perform this task, the rating points are multiplied by a factor of 1.3. This takes account of the fact that women have on average about 2/3 the capacity of men.

• The basis for the evaluation is the probability of health damage. The nature and level of damage is not defined more closely. Account is taken of biomechanical and physiological action mechanisms combined with dose models. It is taken that the internal strain on the muscular and skeletal system depends to a crucial extent on the physical forces to be applied. These physical forces are determined by the weight of the object to be moved, the acceleration values and the floor surface resistances. Unfavourable postures and increasing load duration and/or frequency increase the internal load
  The instructions in the grey box on page 2 of the form must be adhered to.
  
• Summarised evaluations are difficult in the case of a number of manual handling tasks because they go beyond the informative scope of this orientation analysis. They normally require more extensive procedures of risk assessment.
  
• Design needs that can be concluded
  From this risk estimate there is immediate evidence of design needs and approaches. Basically the causes of high rating points must be eliminated. Specially these are:
  
  
  
  • for time rating points, organisational regulations,
    
  • for high mass rating points, reduction of load weight or use of suitable industrial trucks,
    
  • for high rating points for speed of motion and positioning accuracy, use of wheel guides and stop buffers or reduction in workload and
    
  • for high posture rating points, improvement in workplace design.
    
  • The working conditions should always be "good".