The growing demand for easily deployed high speed vessels has so far left one factor on the sidelines.
The growing demand for easily deployed high speed vessels has so far left one factor on the sidelines. People are not really built for the kinds of motion onboard, as Dr Dominic Hudson of Southampton University"s Ship Science Department explaied to MJ.
"The movement isn"t simple," he says. "The boat goes up on one wave, but will typically come down at an angle on another, which means the body also has to brace itself against side to side motion."
It is not something we are particularly well equipped for: Both the lower back and knees take a lot of strain, and although mitigation strategies like shock proof seats help, they don"t cancel out all the problem causing forces.
Dr Hudson"s team at Southampton University looked at a range of stresses the crews of RIBs are subjected to. "While you may well not feel particularly disconcerted by the ride, your performance may still be significantly affected, and that includes both your physical and cognitive abilities", he added. Operators and passengers can thus not think as straight or carry out tasks as well when exposed to the kind of low amplitude, frequent and ongoing shocks which are commonplace in RIBs, not to mention the exposure to wind, spray, sun and cold.
Although there are some studies on bridge personnel aboard merchant boats, Dr Hudson feels that more research is needed on the effects of high speed and exposed vessels.
"We did a three year study that covered the basics but, for example, it seems that the drivers of RIBs come under a lot of pressure. Exposure, the need to make decisions, handle navigation and communication, or recognise legitimate targets for investigation, may combine to seriously affect an operator"s abilities."
The study is timely. High performance vessels are increasingly being used by organisations such as the RNLI. This body has been working with Dr Hudson"s department to model some of the particular stresses on the lumbar region with a view to seeing if it can mitigate against some of the problems with an exercise regime to strengthen certain muscles.
The problems loom larger since the introduction of the EU Physical Agents Directive, written to safeguard land based vehicle operators, A high speed RIB crew falls between two stools.
"You can"t get off, as you would if you were driving a tractor, and the shocks are smaller but repeated, unlike evacuation procedures," explaied Dr Hudson. "So, if you are going to spend a large portion of your working day on a RIB, you are going to rapidly contravene the Directive.