A 3m straightedge can be used to check for plus and minus deviations from a datum. These 3m spaced readings correlate to the reference grid.
A faster way to check the flatness of large areas of a floor is to use digital surveying equipment such as a profileograph.
The test is used to check compliance to certain standards; for example in the UK, BS 8204 – Part 2:2003 and in the US, ASTM E1703 / E1703M.
Ask one of our experts or suggest a definition.