This is a list of some of the terms, abbreviations and organisations that you may come across in relation to scuba diving. Terms marked with an asterisk have a medical meaning and should be used with care.
British Sub-Aqua Club - a worldwide recognised diver training agency.
Also known as DCI or the bends, this is a serious physical problem arising from excessive Nitrogen loads incurred during a dive.
Maximum Operating Depth
The maximum operating depth (MOD) of a breathing gas is the depth at which the partial pressure of oxygen (ppO2) of the gas mix exceeds a safe limit. This safe limit varies depending on the diver training agency, the level of underwater exertion planned and the planned duration of the dive, but is normally in the range of 1.2 to 1.6 bar. BSAC recommends a value of 1.4 bar for normal diving.
In diving terms this refers to a breathing gas mix with an Oxygen content higher than the 21% found in normal air. It is commonly used at Oxygen percentages of 32% and 26%. The reduced percentage of nitrogen is advantageous in reducing nitrogen uptake in the body's tissues and so extending the possible dive time, and/or reducing the risk of decompression illness. As the increased oxygen content becomes poisonous at a shallower depth than air, care must be taken to work within the maximum operating depth of the specific Nitrox mix.
Professional Association of Diving Instructors - a worldwide recognised diver training agency.