diverreb

Alarms are just an additional tool in the safety arsenal.

I can't see much downside to them, but they should always be backed up by checking your handsets on a regular basis to make sure they are giving you correct information.

With the DIVA (Vibrating HUD) on the O2ptima it can either give you your actual PO2 as determined by the secondary handset, or give you warnings based on a % deviation from your setpoint, both high and low, again based on the secondary readings. If those readings get to an extreme situation, either high or low, the DIVA vibrates, which is almost impossible to ignore. It also vibrates if your stack timer (EAC time used in water, as set by the user) counts down to zero.

All of the above is fantastic, as long as the secondary is functioning properly. The reason you always back that up by checking both handsets is if the handsets don't agree, you have a problem.

With this particular unit, if all is well, there is a green flash every eight seconds. My Diva failed on a dive once and it took a while for my brain to process that there was no flash at all after seeing it in normal mode for most of the dive. I was used to seeing green, amber and red, but not nothing. It took a minute or two to realize it was off.

Again, HUD/DIVA's are there as an additional system, but not as the only one to be used.

Richie