PWD
CPWD
Indian Railways
DSIIDC
originally found here :- http://www.ndtindia.org/accrediations.html
Nondestructive testing has been defined as comprising those test methods used to examine an object, material or system without impairing its future usefulness. Nondestructive testing is used to investigate the material integrity of the test object. Non-destructive testing is used to detect abnormalities in physical, chemical or electrical characteristics.