Floor failure over concrete subfloors are often caused by excess moisture levels in the mid section of a concrete floor. This in-depth moisture cannot be detected with conventional pin and pinless moisture meters. The in-situ RH probes can detect the moisture level at a 40% depth and will accurately show if there is too much moisture in the mid section of a slab. The recently up-dated Lignomat RH system complies with the latest ASTM standard F2170-11 in placing the RH Probe within the required distance from the concrete. and restricting the air space, where air can escape upwards to 5/8” from the bottom of the sleeeve.