The present invention provides a detecting apparatus for detecting an abnormal state such as a drop or fall of a person to be observed from a captured image in a real-time manner and realizing improvement in precision of the detection while eliminating the influence of a background image and noise. At a heating area 800, the rolls 350, 352 are preheated, reheated, or maintained at any temperature prior to the rolls 350, 352 being placed into the calendering apparatus 300. A fluorinated polymeric coating is attached to the surface of the spunbond web. Hence the reagents come into contact via said second opening, the reagents react thereby generating steam, and the steam flows through the first opening into the second chamber.