Del. Code tit. 29 § 607
All state agencies shall require that the publicly listed telephone number or numbers for that agency be answered by a person who can direct each call to the proper person or department within that agency during normal business hours. Notwithstanding the foregoing, the satellite offices of state agencies which have no more than 1 full-time employee to provide clerical and secretarial services shall be exempt from the requirements of this section. "Publicly listed" shall mean listed in a local telephone directory (i.e., Government Blue Pages). "Normal business hours" shall mean each Monday through Friday, except those days designated as holidays, during the hours in which the staff of that agency is scheduled to work.
Nothing in this section shall prohibit the internal use of voice mail or other advanced technologies if the agency finds them to be useful. However, any such system shall contain within its message a description of normal business hours and a phone number which will be answered by a person during normal business hours. An automated call distribution system in high volume customer service areas designed to minimize waiting times shall be permissible under this section provided that the system provides callers with an option to speak directly with an agency representative if they should choose to do so.
29 Del. C. § 607