VATSIM Code of Conduct § C12:
All Air Traffic Controllers (ATC) are required to set an appropriate visibility range for the position they are manning. The maximum ranges for a given position shall be based on the following table:
- Clearance Delivery: max. 20 nm
- Ground Control: max. 20 nm
- Tower Control: max. 50 nm
- Approach Control: max. 150 nm
- Departure Control: max. 150 nm
- Enroute (Center) Control: max. 600 nm
Controllers are not permitted to set visibility ranges higher than the maximum ranges set forth in the above table unless they have prior written approval from the VATSIM.net Board of Governors, Network Administrators or Network Supervisors. Controllers found violating this rule shall be first warned to lower their visibility ranges to the maximum range for their ATC position. Controllers who repeatedly violate this rule are subject to the procedures set forth in Article VI. of the VATSIM.net Code of Regulations which could result in removal from VATSIM and revocation of their Certificate Number.
Approved Flight Service Stations, as specified in Appendix B of the VATSIM Global Rating Policy (http://www.vatim.net/network/docs/grp/ ). Network Supervisors and Network Administrators operating in furtherance of their duties are not subject to this rule.