Algorithm - A set of equations incorporated into diving computers in order to compute nitrogen uptake and elimination from changes in depth and elapsed time.
Balanced regulator - Regulator designed to provide a consistent demand effort not affected by cylinder gas pressure or depth
Backward kick- A fining technique for moving backwards. Not an easy, powerful or elegant kick, but useful in many situations. The fins are angled outwards in opposite directions with the legs straight, then swept upwards and towards the diver by bending the knees in the power stroke. The knees may move downwards a bit at the same time by bending at the hips for stability. The return stroke feathers the fins by pointing them backwards in line with the body axis, to reduce forward thrust until the legs are straight again.
Carbon dioxide toxicity - Problems resulting from buildup of CO2 in the blood; they may range from headache and shortness of breath, all the way to sudden blackout.
D.A.N. Divers Alert Network. Nonprofit organization that provides emergency and informational advice and assistance for diving injuries, promotes diving-related medical research and education, collects injury statistics, and offers dive safety services to its members and the diving community.
DCS/Decompression Sickness A condition arising from dissolved inert gases coming out of solution during decompression as bubbles in the tissues, organs and blood vessels of the body causing symptoms ranging from rashes to death.
Decompression Stop A pause during the ascent phase of a dive that a diver spends at a constant relatively shallow depth to allow safe release of inert gases from the body tissues to avoid decompression sickness.