diving safety 



1.

panel of 20 keyswitches, each diver diving rotates a key from the panel and takes it

with them, all 20 keys must be returned and turned in the panel for the engine to

start. emmergency override for lost keys etc.



2. inflatable bag similar to the airbag from a car, inflates after 45 minutes if the

	reset button has not been pressed after returning to the surface,

	bag size 0.25 cubic meters when inflated.



	1. strap plastic box to back

	2. activate by water pressure or 'start' switch

	3. on return press 'cancel' switch, if no return, the box inflates after 45 minutes

		to an air bag which brings the diver to the surface.




3.

0.5 litre air bag on 5 ft light wire attached to shoulder harness to provide a reference for the 'up' direction at deep depths,

	inflatable separately.

