Vaisala cleanroom, at the origins of reliable sensors Industrial Manufacturing and Processes Industrial Measurements Innovations and Inspirations Would you like to have peek inside Vaisala cleanroom? It’s one of the most secret places in Vaisala, yet you will now have a chance to have a look inside. Our Head of Sensor Factory, Hannu, gave us a tour around. And we filmed. This is the place where Vaisala’s accurate humidity, pressure and CO2 sensors are researched, developed and manufactured.