Respiratory mask is an essential equipment for workers in industry, chemical research centers where many harmful gases or particles are present. This mask is needed for the security purpose to avoid harmful gases while working in industry. This paper gives an overview of the technology used for the fit test of the respiratory mask and leakage detection occurred in the mask which makes human health more secure. This paper also provides suitable technology for such system based on Canny edge detection operator. The advantages are its low cost, better accuracy, easy to implement and provides better security for wearer.