Phone No:

+65 65615366 / / +65 97886514

MON – SAT 8.00 – 18.00


Windsor Probe Test

Windsor Probe Test was developed in the mid-1960s by the New York Port Authority and Windsor Machine Company. It is a penetration resistance test used to determine concrete strength by measuring the surface hardness of a concrete element.

Windsor Probe test is carried out in accordance with ASTM C803/C803M – 2017, “Standard Test Method for Penetration Resistance of Hardened Concrete”.  The penetration resistance test is based on the concept that the depth of penetration of a metal probe fired into a concrete surface depends on the strength of the concrete. The equipment used in this test is the Windsor Probe test system using standard power probe.


A minimum of 3 test probes located at not less than 175mm from each other was used at each test location.  The probes must be located at least 100mm from the edge. The probes are fired into the concrete using the driver unit.  The protruding length of each probe which is firmly held in the concrete is measured in millimeters.  The depth of penetration may be calculated from this value and the length of the probe is 79.5 mm.