Control apparatus for ventilating a tunnel

A control apparatus for a ventilator that ventilates a tunnel in response to visibility of the inside of said tunnel, comprising:

• a plurality of picture image input devices configured to take pictures of the inside of said tunnel, and disposed at intervals;
• a visibility index determination device configured to determine a plurality of visibility index values on the basis of processed picture image data of said pictures taken by said respective picture image input devices using a table representing a relationship between said picture image data and a visibility index value corresponding to an actual feeling of visibility for a driver, said relationship being determined by experimentation in advance;
• and
• a feedback controller configured to calculate an operation command for operating said ventilator on the basis of a feedback control value calculated by comparing a worst visibility index value in said visibility index values with a target value of said worst visibility index value.