Computer algorithms

Question:
I would like to have diving safety advice in relation to my job. The basic aspects are checks and repairs of the nets (repetitive yo-yo dives 0 to 20m) and works with the anchors system (repetive deep dives 0 to 50m). The last year I use the Aladin Air (and I have diving profiles for about 370 dives till now)but I don’t feel that the instrument can calculate reliable the decompressions (maybe as a malfacture of the exact instrument or may be as a general weaknes of the software). Is it possible somebody from DAN to check the profiles in relation with the tables or the instrument itself? How can it been done? My checks results that there is big difference between the diving computer and the air decompression tables. After the experience of some small pain in my elbows I have start again to try use the tables (in relation with my work). Do you think that the diving computers are reliable for my job? Where can I find the latest decompresion air tables with big diving times?

Answer:
The Buhlman algorithm used by the Aladin Computers is a rather coservative calculation protocol, with respect to the standard air tables based on the US Navy model.
However the Buhlman model is intended for recreational diving, and multiple prolonged exprosures may fall beyond the longest tissue half times taken into account by it.
Since you are conducting yo-yo dive profiles frequently, it is not surprising that the dive computers indicates shorter total times with respect to the table, since tables consider the total time of exposure at the maximum depth reached, while the computer calculates the real time of exposure at any depth. This influences the final result.
You should also consider that the currently adopted tables ( and computer algorithms ) are never to be considered 100% Decompression Sickness Safe, expecially when multiple, repetitive and aggressive dive profiles are performed, especially if with physical intensive exercise. Your symptoms may simply refer to this statistical possibility rather than to an inadequacy of the tables or computer used.
With regard to your question about tables, you may consider to adopt the current US Navy tables for special exposures, the French Tables ( Comex ) or the DCIEM canadian tables, which are quite conservative ( all can be easily found from specialized libraries).