What does the V-MAC tell you?
What’s on the output tabs?
A load weight/frequency graph
- This is based on the load weight/frequency graph in the MAC. It has been flipped round and scaled.
Vertical bars on the graph summarising the data you have entered
- These are calculated and appear automatically. The screen grab below is from the first worked example. The tall coloured bars are ‘summary bars’ that tell you about the overall demands of the job. The smaller pale blue bars and the values above them show the numbers of items handled in 1 kg steps.
A shift length box
- This is for you to enter the actual shift length (in hours and minutes). The boundaries of the graph move to take account of the shift length.
A summary table
- This helps you to identify the aspects of the job that increase the risk. It is colour coded to identify each summary bar and shows you its height and colour band.
- The overall risk is shown by the overall colour band/score at the bottom of the summary table. This is what you should enter into the interactive MAC score sheet before carrying on with the rest of a MAC assessment. Only the overall risk has a score as well as a colour band.
- Just below the Overall colour band/score line in the summary table, you will find the total load, the total number of carries, and the total carry distance.
- Here’s the summary table from the first worked example.
An explanation of the colour bands
- They are the same as in the MAC and indicate risk level: Your aim should be to reduce the risks by moving risk levels towards the ‘Green’ colour band.
|Colour band||What it means||Action to take|
|Very high level of risk
Such operations may represent a serious risk of injury and should come under close scrutiny.
|Eliminate these lifting operations as the highest priority.|
|High level of risk - Prompt action needed
This may expose a significant proportion of the working population to risk of injury.
|Ask if you can:
|Medium level of risk - Examine tasks closely||Ask if you can:
|Low level of risk||Consider the vulnerability of special risk groups (such as pregnant women, or young workers) where appropriate.|
How to interpret the data - first look at the weights of individual loads
The V-MAC takes the weights you enter and rounds them to the nearest kilogram. It then plots them on the graph so the height of each bar represents the number of times that a particular weight is handled in a shift. The number of lifts of that weight is shown above each bar.
Think about the risks from these individual loads first. Start with the heaviest weight and ask what it is and why it is being handled in the way it is.
Then ask if you can, as far as is reasonably practicable:
- Eliminate the manual handling of these items?
- Mechanise the handling?
- Make the loads lighter, perhaps by splitting them?
Use the Excel workbook to ask ‘What if …?’ questions and to see the effect on the graph. For example, if someone handles 300 items weighing 30 kg, you might decide to replace them with 600 items each weighing 15 kg. That would make individual loads lighter but increase the total number of lifts the worker carries out.
Once you have looked at the heaviest weight, work from right to left across the graph so you look at the next heaviest weight until you reach the ‘Green’ zone.
How to interpret the data - use the summary bars to look at the overall demands of the job
After looking at the individual loads, you should look at the summary bars on the graph and in the summary table.
- Previous page: Entering data into the V-MAC
- Next page: Values in the summary table and what they mean