Aeris Epic Operating Manual page 120

SWITCHING GAS MIXES (NORM only)
During NORM Dives, the PIC can be manually switched from GAS 1 to GAS 2 to GAS
3, changing FO2 displays and calculations from the FO2 value set for GAS 1 to the FO2
value set for GAS 2 to the FO2 value set for GAS 3, and if TMTs (Transmitters) are used,
changing Pressure related displays and calculations from TMT 1 to TMT 2 to TMT 3.
NOTE: Switching the EPIC from one GAS (and TMT) to another cannot
be performed while on the surface, and during dives when TMT -3
USE is set for Buddy Pressure Check.
Every dive begins with GAS 1. 10 minutes after surfacing from a
multiple gas dive, the EPIC's operation defaults to the GAS 1 FO .
1 0
Access to NORM DIV Gas Switching screens can only be
accomplished during the time that a NORM DIV MAIN
screen is being displayed and cannot be performed during
the time that an Alarm is sounding.
NOTE: If a Switch to a new Gas Mix would
expose the diver to a prohibitive PO level of
1.60 ATA or greater, the Audible Alarm will
sound, the red LED will flash, and the message
DONT > SWCH will scroll at the top of the display
(Fig. 106) until acknowledged by pressing/
releasing the S button momentarily.