Towers or facilities for transmitting or receiving any signal, broadcast or communication as part of a business (other than commercial mobile services) or as part of a commercial television, A.M. radio or F.M. radio enterprise may be erected, altered or used only in a Business or Industrial District in the Town of LaFayette within the meaning of the Zoning Law, as amended, and may be so erected, altered or used only upon findings by the Town Board that such structure or use, together with such conditions and safeguards it may impose, is necessary for the public convenience; that such structure or use is not detrimental to the public health, safety or welfare; and that the location proposed therefor is appropriate. Towers or facilities used exclusively for the broadcast or communications of official law enforcement, fire control or medical emergency matters are exempt from this provision.