The Probe on the Inova-400 will be changed as required and requested by users on the system, but generally not more often than every two weeks. Also, in order to allow for current reservations, a probe change will not be scheduled until at least 3 days after it is requested. In order to request a probe change, submit the following form. If you include an e-mail address, a copy of this request will be forwarded to you for your reference. Notification of scheduled probe changes will be through the status screen on the reservation terminals, NOT by E-mail.