Condtional formatting (Applying data bars)

Some help needed.
I am trying to utilise the data bar function in conditional formatting.
I am generating data that needs to be within a specific range. For example the lab data may be 5, and the desired range between 10-20.
I need to generate a bar to relate the data to the desired range. In this case it would be low.

I am currently trying to line inserted graphs up with cells.

I have categories

Very Low Low Acceptable High Excessive
In this case the acceptable range is 10-20. The data is 5 so it would plot low.

Can anyone help with formulas utilising data bars

Example.pdfApologies, Unfortunately I cant post spread sheet. I have PDF an example.
If you use the top line as an example. ECEC, the range is 10-25 the results 6.56. I am currently lining up a bar graph across several cells.
I would like to merge the cells and get the data bar to plot according to the result. See PDF