Esd bench mat. How much coverage??

Hi.
I have just finished building a new workbench. The top measuring 2000mm x 900mm.
I would like to purchase some ESD rubber matting for the work top. My question is, how much covering will be enough? These mats are expensive here in S. Africa. Is it a good thing to cover the whole top, or more practical to do only a section??

You need to cover any area with ESD matting that will have electronic parts being assembled or tested placed on it. Instruments and power supplies don't need to be on a mat.

Remember to make sure that if you're wearing a wrist strap that there's a 1M ohm resistor in series with the strap and your ground (earth) connection. This is a safety requirement so that you're not solidly connected to ground with no current limit in case you touch the wrong thing in a higher-voltage circuit.