Why do you have Hydrostatic Release units on board your vessel? What happens inside an HRU when exposed to hydrostatic pressure?
The installation of an HRU is preferably performed by a raft service technician, the material in this lessons show you what to look for when checking for a correct installation.
Hopefully, in the unfortunate event, an abandon ship is necessary the HRU will not be used. Instead, a manual release with a release hook is favourable. The Easy Release for H20 is an accessory that will make this significantly easier and safer.