TABLE A: 50m dive for 30min
Depth (m)	Time (min)	Ambient Pressure (bar)	Gas	Gas Used (litres)
50	30	6	air	3600
Ascend 50 to 18	3	6	air	360
18	1	2.8	air	56
15	3	2.5	air	150
12	6	2.2	air	264
		Total Air (RMV 20 l/min)		4430
9	8	1.9	80%	228
6	4	1.6	80%	96
4.5	21	1.45	80%	457
		Total 80% (RMV 15 l/min)		781