[Problem to be Solved] A device and a method for efficiently decontaminating a device used to culture cells are provided.[Means for Solving Problem] A decontamination device for decontaminating a device used to culture cells, manipulate microorganisms, or perform a sterility test, the device comprising an ultrasonic atomizer that atomizes a peracetic acid disinfectant by using ultrasonic oscillation to discharge droplets, a diffusion fan, a temperature-humidity sensor, and a controller.
