• Concrete Thickness Gauge

Concrete Thickness Gauge

Verify Concrete Slab


  • Determines Thickness
  • Detects: Honeycomb • Voids • Cracks • Delamination

No need to drill, core or excavate to determine concrete slab thickness

Applicable For:

  • Concrete Slabs
  • Concrete Pipes
  • Tunnel Linings
  • Core Depth Planning
  • Precast Panels
  • Walls
    • Precast
    • Precast Tilt-up
    • Cast-in-Place
  • Concrete Pavements
    • Parking Garages
    • Airport Runways

Based on the Impact Echo Principle

Meets ASTM Standard C1383-04(10)

The CTG-2 is a hand-held, battery powered, nondestructive system for measuring the thickness and integrity of concrete slabs, pavements, tunnel linings, walls and other plate-like structures using the Impact Echo principle. Requires no special knowledge or training connect the CTG-2 to your laptop or tablet* and start testing with Olson’s WinCTG2 software. For greater accuracy, calibrate the unit at a location of known thickness to obtain the concrete velocity for that job.


  • Ruggedized, hand-held test head with integrated displacement transducer and solenoid impactor
  • Switch between English (inches) or Metric (millimeters) units with the click of a button
  • No coupling agents required for use of test head on concrete
  • Easy velocity calibration at known thickness location, or use Olson’s default parameters
  • Works on cured, hardened concrete in air or on grade
  • Thickness data table can be imported into most spreadsheet programs
  • Works through paint and most types of bonded ceramic tile
  • Save results for later review
Thickness Range
  • 3.2" to 20" (81 mm to 50.8 cm)
  • Optional thick mode tests up to 6' (1.8m)
Data Collection Works with most Windows 7 and Windows 8 devices
Accuracy ± 2% when calibrated on a known thickness location
Frequency Resolution 10Hz
Software Features Olson’s WinCTG2 Software is used for data acquisition and analysis
Number of Samples Acquired Per Test4,545
Sampling Rate45,454 samples/second
Max. Nyquist Sampling Frequency22,700 Hz
Report Capability use X and Y coordinates to set up a test grid. Generate a thickness summary table which can be exported to most spreadsheets in comma separated format
Weight5 lbs (2.27 kg) combined weight of test head, batteries, cables and protective case
Cable Length for Test Head3 ft (91 cm)
PowerUses four readily available, nonrechargeable CR123A 3V long life lithium photo batteries

*To test concrete and acquire data, the CTG-2 system must be used with a Windows 7/Windows 8 computer or tablet running Olson Instrument’s WinCTG2 software. The required computer or tablet must be provided by the user.