Protects against Hypercapnia
Lungfish rebreathers are equipped with an optical CO2 monitor accurate to 0.01 KPa regardless of depth and background gas. This gives you a real-time indication of scrubber performance which will alert you to the presence of any CO2 well in advance of it becoming a risk.
The actual CO2 concentration of your inhaled gas is shown on the default dive screen, while separate alarms warn the user of a low level of CO2, indicating a functional though depleted scrubber, and a higher level that would necessitate bailout. You can easily make your own decisions as whether you want to purge the loop, reduce their exercise rate, carry on and finish the dive closed-circuit, or end the dive.
All CO2 readings are recorded along with the dive profile.