After that each keypad has to be inspected visually by the user to detect cracks or similar damages.

A common particle used to detect cracks is iron oxide, for both dry and wet systems.

Its most common application is to detect and size cracks in welds.

Under a microscope, he detected cracks that revealed a yellow pigment.

Or maybe something as simple as putting strain gauges around your house to detect cracks forming.

The system can detect cracks in the field as small as 0.01 inches in an actual structure.

Blade inspection method is a system to detect cracks in the main rotor blades.

The ultrasonic tests can detect even microscopic cracks.

Images from satellites orbiting Mars have detected cracks near impact craters.

Exposed engine parts could then be tested with probes that use electrical currents or sound waves to detect tiny cracks.