Dear Γιώργος,
Information from the following link might be of interest:
http://www.apdiving.com/inspiration/...ion/index.html
Depth Limits: 40m - max. Depth with air diluent.
100m - max. Depth at which all rebreather parameters are proven: CO2 endurance, O2 control and work of breathing.
100m - the limit of the CE approval.
110m - max. Depth at which the work of breathing has been tested using Trimix diluent.
150m - max. Depth at which the work of breathing has been tested with an Heliox diluent.
160m - Depth at which all components are pressure tested during type approval (not during production).
Warm regards,
John