Disinfectants and antiseptics play a vital role in the infection control. They act as a crucial armament against transmission of nosocomial infections combating disease outbreaks. In-uses test study was done on 100 disinfectants / antiseptics. Samples were taken from the various departments of the MMIMSR, Mullana. Ten ml sample of each disinfectant / antiseptic being used in the hospital were taken and processed by the method of Kelsey and Maurer (1974). Read the test as showing failure of disinfection. If there was growth in more than five drops on the plates. The organism thus grown it indicated failure of the disinfectant / antiseptics were picked up and further identified on the basis of colonial morphology and biochemical characters. In the present study 5 samples which failed the test, revealed the growth of Ps. aeruginosa. So, it is concluded that all the disinfectants and antiseptics should be used in proper concentration and monitoring. Instruction of manufacturing should be strictly followed.