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The great seacock safety debate
An ordinary brass tailpipe found during the survey of a 10-year-old boat. It was so badly dezincified that the wall simply crumbled under a light tap - photo: Paul Stevens
Last summer, Yachting Monthly ran some articles on how a simple seacock can sink an otherwise seemingly healthy boat, says Peter Nash. However, the RCD and standards came in for a bit of a bashing…
Nigel Saw, technical manager for the British Marine Federation (BMF), and Udo Kleinitz, technical manager for the International Council of Marine Industry Associations (ICOMIA) both feel the standards have been midunderstood.
So, in the interests of trying to get this all sorted out, Boating Business asked Mr Saw and Mr Kleinitz to put their side of the story - which is printed here in its entirety. Following their article is a short comment from Paul Stevens, the surveyor quoted extensively in the Yachting Monthly reports.
While I can see both sides of this story, I’m very pleased the problem of seacock safety was highlighted. The Yachting World articles caused many owners to check their boats, sometimes revealing – and replacing – seacocks that were obviously endangering craft and sailors.
And after reading both articles, perhaps the wording of the standard needs to be tweaked a little?
From Nigel Saw and Udo Kleinitz
Much has been written both in the UK and in Germany in past months about the failure of seacocks, the Recreational Craft Directive (RCD) and the standards produced by the International Standards Organization (ISO).
The UK boat building industry represented by the British Marine Federation (BMF) and the International Council of Marine Industry Associations (ICOMIA) take an active part in producing and maintaining the various ISO standards that support the essential requirements of the RCD.
The involvement by these organisations as well as other trade and standard making bodies around the world are motivated by the desire to ensure fair trade throughout Europe and the need to produce craft that meet the expectations of both the regulators and consumers alike.
The RCD has four ‘Essential requirements’ that relate to seacocks. ER 3.1 deals with the need for the craft to be strong enough in all respects, ER 3.3 deals with buoyancy and floatation. ER 3.4 deals with openings in hull and deck and ER 3.5 deals with flooding.
These essential requirements are referenced in an Annex ZA to the European version of the ISO standard referred to as the ‘Harmonised’ standard that is quoted in the Official Journal of the European Union.
Seacock failure
Over 10 years ago reports of seacock failure were bought to the attention of the boat building industry and the need to use the appropriate material for seacocks and to take into account other factors such as electrolytic action.
The then current ISO standard ISO 9093-1 for metallic seacocks was published in 1998 and has been reviewed and published without change ever since that time. ISO standards are developed by international committees for use by any person in the world.
Although the official language is English they are also translated into other languages and are written to avoid misunderstanding and ambiguity. However the wording of these standards needs careful study, as it maybe that without an understanding of the meaning and intent of any particular clause a wrong interpretation can be made.
The use of these ‘harmonised’ standards that have been approved as meeting the essential requirements of the RCD are however not mandatory and boatbuilders are free to use any material they consider appropriate, it still of course remains a requirement that the whole craft meets the requirements of the RCD.
Within ISO 9093-1 are three clauses dealing with material selection. Clause 3.3 of the standard defines ‘corrosion resistant’ as being: “material used for a fitting which, within a service time of five years, does not display any defect that will impair tightness, strength or function”.
Exactly what it says
This means exactly what it says in that there should be no signs of deterioration when used in the specific application within five years, it is certainly not suggesting that this is the life of the fitting!
Clause 4.1 within the standard deals with the selection of materials and states: “The materials used shall be corrosion resistant or shall have protection against corrosion, taking into account the various and changing media that pass through the fitting”.
Again no time limit is quoted or suggested.
And the third clause 4.2 dealing with material combinations requires: “The combination of different materials shall take into consideration the possibility of galvanic action.” It is considered that many corrosion related failures may be due to galvanic action and there have been an increasing number of problems reported as being due to electrolytic action particularly with the increasing amount of electrical equipment being installed.
In the case of the articles and letters about the premature failure of seacocks the cause of these failures has been blamed upon the RCD, the ISO standards, and the boatbuilding industry in general.
From the evidence presented it appears that failures have been due to the incorrect selection of materials and/or installation and not as result of using seacocks certified to meet the ISO standard 9093-1.
From Paul Stevens, a founding member of British Marine Surveyors Europe and the author of the first Yachting Monthly article
King Canute could not hold back the tide, nor can any committee stop ordinary brass dezincifying in salt water.
The ridiculous five year corrosion definition opens the door for ordinary brass, whereas had the original committee responsible for the ISO, and those reviewing it subsequently, done their research properly they would have known that appropriate bronze fittings in common use for nearly a century, had a service life of at least 25 years. The more recent DZR brass has also proved suitable.
Modern “seacock” installations typically have three components and all must be beyond doubt.
Mr Saw seems to be saying that ordinary brass fittings “meet the expectations of both the regulators and consumers alike”. Well a huge number of consumers, myself included, disagree, brass does not meet our expectations and we hold the regulators responsible.
Yachting Monthly and myself have communications from far and wide documenting brass fittings failing or in critical condition. Such is progress.
- See more at:
http://www.boatingbusiness.com/news101/fitting-out/exterior-fitting-out/the-great-seacock-safety-debate#sthash.1ze3mRR2.dpuf
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