Main objective of this study is to observe the success of directly observed treatment, short-course (DOTS) programme in West Bengal in respect of safe disposal of acid-fast bacilli (AFB) positive sputum specimens. The present study focused the mycobateriocidal effect of supplied phenyl in the DOTS clinics at Hooghly and Burdwan districts, West Bengal, India, where the standard direction of disposal is being followed. Viability of Tubercle bacilli in different concentrations and contact times with that Phenyl has been observed in this study. Sputum samples were examined for (AFB) by Ziehl-Neelson (ZN) staining technique. The existing protocol for using the phenyl with sputum sample is equal volume of sputum and 5.0% Phenol i.e (1:7 dilution of phenyl). The contact time required is about 18 hours approximately. The study focused that concentration of phenyl may be lowered upto 1% without disturbing the mycobacteriocidal effect. So, the dilution which is used in DOTS center is above the threshold dilution of phenyl and so there is no question about the bio-safety in this connection with quality of disposal of sputum of positive patients in this concern.