There are several things that should be done as soon as possible after the dive is over.
First, close the DSV and change your set point to 0.19 PPO2 on the controller. This will prevent the unit from firing the solenoid and wasting oxygen when the unit is not in use.
Next, it is good to check the battery voltages to know if the batteries will need replacing before the next dive.
Also, note the pressure remaining in the oxygen and diluent cylinders, and the total dive time to determine scrubber usage.
The cylinder valves can now be closed and the lines purged by pressing the manual add buttons.
(***Never turn off the cylinder valves before you are out of the water and have removed the rebreather! ****)
If the unit was dived in salt water, soak it in a freshwater tank if possible and then spray it off thoroughly with fresh water.
Turn off the controller and HUD to maintain battery life. Make sure the electronics do not come back on automatically due to the wet switch.
This is all that is needed if the unit will be dived again that day. Otherwise, the breathing loop should be disassembled and sterilized. It is recommended to do this within 12 hours after diving to prevent the growth of mold and bacteria in the loop.
Begin the cleaning procedure by disassembling the loop. Remove the DSV, loop hoses, counterlungs, scrubber end cap, and scrubber canister.
It is not necessary to remove the electronics head from the unit for cleaning. Simply wipe down the inside of the head with a clean towel and allow it to dry.
Remove the EAC scrubber cartridge or granular media and discard. All of the other pieces of the loop can now be thoroughly flushed under warm running water paying special attention to the inside of the exhalation side hose and counterlung.
Next, mix up a solution of Steramine in a bucket according to the directions on the bottle. Submerge all loop parts except for the electronics head and the counterlungs in the solution for a minimum of 1 minute to sterilize. Do not leave them in the solution for an extended period of time, as over exposure to the chemicals can damage mushroom valves and seals.
Once sterilized, remove the parts from the solution and thoroughly rinse inside and out with fresh warm water.
To sterilize the counterlungs use a cup to pour some of the Steramine solution into each counterlung.
Cover the openings and shake the counterlung for 1 minute, then dump and rinse the inside thoroughly with fresh warm water.
Shake excess water off of all the components and then spread them out on a clean towel to dry. Hang the loop hoses and counterlungs to dry. Allowing components to dry completely is the best defense against the growth of mold and bacteria.
For reference, see the Post Dive Checklist in the Checklists section.