2007, Piran, Slovenia

Environmental Ergonomics XII
Igor B. Mekjavic, Stelios N. Kounalakis & Nigel A.S. Taylor (Eds.), © BIOMED, Ljubljana 2007
Table 4. 50% Survival time from UKNIIS 2006 (N=1593)
Water Temperature Not Worn Worn
5°C 3.6 >24
10°C 5.7 >24
15°C 9.0 >24
Tables 3 and 4 give estimations of 50% survival time with and without buoyancy aids. All
analyses were performed using Minitab.
DISCUSSION
The new data set do not provide estimations that are significantly different from the original
data set. However, the increase in the number of cases has decreased the standard error
around of the predictions, as a consequence data collection should be continued.
Even with the increase in cases, the results should be interpreted with a degree of caution. For
example, Tables 3 & 4 focus on the use of buoyancy aids, but the cases which constitute this
Table will include individuals with different types of lifejacket, different clothing, different
physique and gender (i.e. complicated interactions). Even with the large number of cases, the
number contributing to extreme scenarios (e.g. immersions longer than 4 hours, very cold or
warm water) is relatively small, which makes predictions less reliable and more qualitative
than quantitative.
ACKNOWLEDGEMENTS
This work was funded by the US Coastguard & US Army.
REFERENCES
Oakley, E.H., Pethybridge, R., 1997. The prediction of survival during cold immersion:
Results from the UK National Immersion Incident Survey. Institute of Naval Medicine,
Gosport.
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