Dive Computer Use in Recreational Diving: insights from the DAN-DSL Database

Data from the DAN Europe Diving Safety Laboratory (DSL) suggest that
approximately 95% of recreational diving is carried out today using a dive
computer. The most widely dived computers/algorithms, irrespective of
brand, use the Bühlmann ZHL-16 or the Wienke RGBM algorithm, with
roughly a 50/50 distribution across the DSL population. The vast majority of
the 167 recorded decompression sickness (DCS) cases occurred without any
significant violation of the respective algorithm’s limits, i.e., most occurred
while using gradient factors that were well below the maximum allowed by
the algorithm. The DSL database and field research also show that many
other physiological variables may be involved in the pathogenesis of DCS,
even within computed “safe” limits, causing a variable individual response
despite similar inert gas supersaturation levels. We conclude that the current
computer validation modalities, although important and useful as a basic
benchmark, still allow a probability of DCS beyond ideal levels in a
recreational setting. In order to limit unexpected DCS a more aggressive
“biological” approach is recommended that is able to identify and then
control the most significant physiological variables involved in the
pathogenesis of DCS, in addition to the inert gas supersaturation levels.