Concrete Thickness Gauge (CTG-2)

Verify Concrete Slab Thickness & Integrity
No Coring — No Drilling — No Excavating

The Concrete Thickness Gauge (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 Concrete Thickness Gauge to your laptop or tablet* and start testing with Olson's WinCTG2 software. For greater accuracy, simply calibrate the CTG-2 by testing a point of known concrete thickness to obtain the concrete velocity for that job.

NOTE: Impact Echo testing is available as an add-on for the Freedom Data PC and the NDE 360 platforms.

Impact Echo Case Studies

Materials Tested:
  • Concrete
Test On:
  • Concrete Slabs
  • Pavements
    • Parking Garages
    • Airport Runways
  • Tunnel Linings
  • Walls
    • Precast
    • Precast Tilt-up
    • Cast-in-Place
  • Precast Panels
  • Concrete Pipes
  • Core Depth Planning
ASTM Standards:
  • C1383-04(10)

Key Features

Ruggedized, hand-held test head with integrated displacement transducer and solenoid impactor Switch between English (inches) or Metric (millimeters) units with a touch of a button
No coupling agents required for use of Impact Echo 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 popular 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) with built-in solenoid, to 6' (1.8m) when using a hammer. Data Collection: works with most Windows 7+ 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/test: 4,545
Sampling Rate: 45,454 samples/second
Max.Nyquest Sampling Frequency: 22,700 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 Weight: 5 lbs (2.27 kg) combined weight of test head, batteries, cables and protective case
Test Head Cable Length: 3 ft (90 cm)
Power: Uses four readily available, CR123A 3V long life batteries *To test concrete and acquire data, the CTG-2 system must be used with a Windows 7+ computer or tablet running Olson Instrument's WinCTG2 software. The required computer or tablet must be provided by the user.

Hands-on training is available for all of our NDE test methods at our Wheat Ridge, Colorado (USA) location, which is a suburb located approximately 15 minutes northwest of downtown Denver. Training may be available at your location by one of our agents/engineers upon special arrangement.

Save money! Contact Olson when adding on to an existing system, or purchasing multiple systems as some of the components are common to other test methods.

For complete details about any of our products, call our toll free number at 1-888-423-1214 or email Olson Instruments: