The maximum ascent rate for the MK 16 is 30 feet per minute. During ascent,
when water pressure decreases, the diaphragm dump valve compensates for
increased gas volume by discharging the excess gas into the water. As a result,
oxygen in the breathing gas mixture may be vented faster than O2 is replaced by
the addition valve. In this case, the primary display may alternate red/green before
the low-ppO2 signal (blinking red) appears. This is a normal transition period and
shall not cause concern. Monitor the secondary display and add oxygen by
depressing the bypass valve during this instance.
