By Tom Keeling MIMarEST and Peter Brookes CEng, MIET, affillIIMS. Tom Keeling and peter Brookes are inland waterways-based marine surveyors. Both have run independent consultancy businesses in this sector for many years, specialising in the survey of steel thickness of narrowboats and their hulls.
Marine surveyors and boat owners are regularly heard to say there is a minimum 4.0mm of hull thickness required at time of survey of a steel narrowboat. Some brokers even publish videos of such information, with some surveyors enforcing it (Whilton Marina, 2012 and 2016). Boaters are subject to it and repair often follows. In a recent article, Geoff Waddington (2021) explains there is confusion in the industry about wastage limits, and consequently acceptable residual hull plate thicknesses, and opinions among surveyors ‘vary wildly’, with some quoting 3mm acceptable minimum plate thickness, others using percentage loss. This short paper explores what a standardised acceptable limit for diminution, and therefore residual steel plate thickness for narrowboats, could be. It describes a variety of methods of calculating the design plate thicknesses (scantlings) and the minimum acceptable residual plate thickness. In doing so, this paper aims to serve as a guide for inland waterways marine surveyors, boat owners, repairers, and insurers alike. Continue reading “Minimum Steel Thickness for Narrowboats: A discussion paper”
It seems we have gone full circle. Cargo ships powered by sail were lost to us a century or more ago, and to the current generation such vessels are regarded as outmoded transportation from a bygone era. But now they are back, more sophisticated and sustainable than ever. Recently I read about the Anemos, which has claimed the title of the world’s largest sailing cargo ship as she made her inaugural voyage from Concarneau, South Brittany, France. 
Saudi Red Sea Authority yachting regulations have been written and published for the first time by the authorities.
This is a remarkable story, one of my favourites for ages, which fortunately had a happy ending. What caught my eye specifically were the details of the good Samaritan vessel – a floating sauna – which came to the aid of a sinking Tesla. I must have led a sheltered life as I was completely unaware that such craft existed and that they are indeed popular in Norway and can be hired by the hour! And being a skipper of a floating sauna sounds like a very cool job – never getting cold on the job either! 
The marine environment takes a toll on coatings, and to keep up with maintenance, most ships’ crews use oil-based paints and finishes almost every day that the weather allows. These materials come with an inherent fire risk, the National Transportation Safety Board (