PBO - DZR seacocks

[Ammonite]

To be fair to BSD, he does say in his article that it is the quality of some DZR valves that is in question, and that although the valve may be made of DZR other parts such as hose tails may be of other material and suspect. Is there any type of quality kite mark that gives confidence when buying DZR so you know exactly what you are buying and avoid an expensive mistake??
Personally, I think I would use Tru Design composite fittings as replacements as you know exactly what you are getting. The only problem I see with them is the physical size of the larger fittings, if space is limited.

If you are buying new it's easy to know what you are getting when it comes to DZR. Asap-Supplies, Aquafax etc all list the make up of the various components in detail and if DZR isn't up to the job I haven't got a problem with this but I would like to see the evidence. If they are going to knock DZR because someone has fitted a brass hosetail you might as well extend this to the hose clips and hose its connected to.
TruDesign do look good and I was sorry to hear their factory burnt down in July. Apparently it's going to be out of action for at least 6 months and they were looking for an alternative supplier.

 

[coveman]

If you are buying new it's easy to know what you are getting when it comes to DZR. Asap-Supplies, Aquafax etc all list the make up of the various components in detail and if DZR isn't up to the job I haven't got a problem with this but I would like to see the evidence. If they are going to knock DZR because someone has fitted a brass hosetail you might as well extend this to the hose clips and hose its connected to.
TruDesign do look good and I was sorry to hear their factory burnt down in July. Apparently it's going to be out of action for at least 6 months and they were looking for an alternative supplier.

Thanks for pointing these suppliers out - its useful to know where you can obtain genuine equipment.

 

[lustyd]

Skin fittings should last 30 years, not five

I think I'd rather they lasted 5 than 30, at least then they're a regularl maintenance item. After 30 years it's much more likely people will ignore and hope for the best. That said, all of mine will be going TruDesign at next lift out whenever that may be

 

[alan_d]

I think I'd rather they lasted 5 than 30, at least then they're a regularl maintenance item. After 30 years it's much more likely people will ignore and hope for the best. That said, all of mine will be going TruDesign at next lift out whenever that may be

Hmm. An interesting idea, but could prove expensive if applied to other items of inventory as well. I thought planned obsolescence was generally deprecated these days, and it certainly sits uncomfortably alongside ideas of sustainability.

 

[Stemar]

If they last 5, someone is going to try to make them last 10, which will likely end in tears because they're corroding. albeit slowly. If they last 30, chances are they'll last 60, because there's no significant corrosion going on or they couldn't be expected to last 30.

 

[Elessar]

Why is PBO not commenting?

 

[Elessar]

Thoroughly recommend these guys.
replaced all 8 on mine earlier in the year.
Surejust

 

[CM74]

Thoroughly recommend these guys.
replaced all 8 on mine earlier in the year.
Surejust

+1 for them, I used them for 2 on my boat - they seemed well made, and when I asked for them they provided some DZR backnuts free as well - result!
As a replacement for elderly gate valves that didn't shut they are like night and day

 

[Poey50]

I've just read the article in PBO which seems thoroughly confusing. The person who wrote it is trying to mash together a number of different factors and I don't trust that they have understood the issues and, because of this, may be quoting their 'experts' inaccurately. It is a journalist article rather than a technical one. One issue here seems to be the Recreational Craft Directive which ... uh ... directs that seacocks should be changed every five years. The author seems to have reverse engineered this statement to assume that this also applies to DZR assuming that this is indeed the safe lifespan. At least, that's my reading.

If some DZR really only lasts only 5 years and some lasts in excess of 3-4 decades then, of course, the designation DZR or CR is itself rendered meaningless in guiding safe installation. The more likely explanation is that the author has just got it wrong.

 

[Habebty]

I've just read the article in PBO which seems thoroughly confusing. The person who wrote it is trying to mash together a number of different factors and I don't trust that they have understood the issues and, because of this, may be quoting their 'experts' inaccurately. It is a journalist article rather than a technical one. One issue here seems to be the Recreational Craft Directive which ... uh ... directs that seacocks should be changed every five years. The author seems to have reverse engineered this statement to assume that this also applies to DZR assuming that this is indeed the safe lifespan. At least, that's my reading.

If some DZR really only lasts only 5 years and some lasts in excess of 3-4 decades then, of course, the designation DZR or CR is itself rendered meaningless in guiding safe installation. The more likely explanation is that the author has just got it wrong.

My thoughts as well.

I think a clarification on this article from PBO might help?

 

[Tranona]

The RCD says nothing about changing seacocks every 5 years - only that they should have a minimum life of 5 years. It also says nothing about what material they should be, but the use of plain brass was (and still is) almost universal for European production builders - including the "quality" ones as Vyv Cox pointed out earlier. Despite the fact that hundreds of thousands of such fittings were (and are) in use, there really is not an epidemic of failures and sinkings that some people imagine. Bronze was almost unique to the USA and UK and DZR is a UK development primarily for the domestic water industry, but of course useful for boats.

It is also worth noting that failure of ball valves, whatever the metal is very rare (other than seizure and handles/spindles corroding), it is fittings, usually hosetails rather than through hulls that dezincify. It is also the case that even dezincified tails rarely fail on their own as they are not normally under any stress, but can break when subject to shocks such as being hit by a loose heavy object.

As to the confusing (and wrong) statements in PBO (and YM) on this subject, Vyv and I have taken it up several times with both editorial and individuals, and one one occasion a correction was published in a prominent place. However given the turnover of staff and writers, all this knowledge gets lost. It still amazes me that so called expert surveyors still do not understand the subject, in much the same way as many still have not grasped the issues surrounding the related subject of the fitment of anodes

 

[Poey50]

The RCD says nothing about changing seacocks every 5 years - only that they should have a minimum life of 5 years. ...

That's one source of the muddle then. From the article "According to the Recreational Craft Directive these [skin fittings] need to be replaced every five years, a lifespan that many people in the industry believe is far too short". And later "DZR contains 32% zinc and was developed for the domestic plumbing market, but when the RCD came in and boatbuilders realised skin fittings only needed to last five years, they used it on boats too." (My emphases.)

 

[Poey50]

I've looked at a few articles on this now and I can see that Tranona is correct. There is quite a widespread and long-term misunderstanding on the meaning of of the Recreational Craft Directive. Effectively, as Tranona says, the RCD only specifies a minimum life. It follows logically that various kinds of seacocks will both meet and exceed this.

However, a logical fallacy chain seems to have taken root that goes something like this.

1. The RCD specifies that seacocks have to last for five years. [True]
2. This is a very limited standard. [Not true - it misses out the notion of minimum.]
3. Because builders will be following this poor standard then it is important to change seacocks every five years [Untrue it assumes a minimum standard has become a maximum one.]
The article seems to take a further step apparently supported by 'quotes' from some 'experts'.
4. Since seacocks have to be changed every five years and DZR is a seacock then DZR must be changed every five years. [Untrue.]

Here's a 2011 Yachting Monthly report in which the first three mis-steps are made.

https://trip.ayy.fi/wordpress/wp-content/uploads/2014/08/Seacocks.pdf

Although there seems to be widespread confusion there are some reliable interpretations. The RYA look completely sound on this, for example.

The international standard specified in the Recreational Craft Directive for metallic sea-cocks and other through-hull fittings is ISO 9093-1:1998.

This requires sea-cocks and other through-hull fittings to be made of a material that does not display any defect within five years of service that would impair its watertight integrity.

This does not mean that components need only have a service life of five years but rather that components must function for at least five years without displaying any defect.

As far as the RYA is aware, since this standard was introduced in the late 1990s there has been no evidence of widespread failures of sea-cocks and through-hull fittings that met this standard.

 

[Tranona]

The missing bit in the story is the myth at the time which said that following the RCD, builders suddenly saw an opportunity to safe huge sums of money - remember many boats have upwards of 10 seacocks - and switched to cheaper lower quality fittings.

Simply untrue, most were already using plain brass. We tend to see all this from the perspective of UK practice, as if this was somehow superior. True, many builders in the UK did use Blakes, but equally many used awful gate valves, often plain brass. Skin fittings and hose tails were only readily available in bronze or brass and no doubt some brass were used. It is only recently that DZR fittings became commonly available- from Italy. It is worth noting that few brass valves come from China - most are Italian from what I have seen. By 1997 when the RCD came out the UK industry had all but disappeared, so although much of it was developed in the UK it reflected more the standards that already existed in European countries. The main aim of the RDC was to establish a common EU standard so it was inevitable that the interests of the big European builders (and markets) dominated.

 

[doug748]

The whole business is, and was, a disgrace. Who knows who originally thought it was a good idea to specify inferior materials, and why? I guess we will never know.

Imagine buying a new boat and having to replace major, unstressed, safety critical components after 5 years in order to sell it, a shambles.


Any road, the message is clearly getting through, I see Beneteau are now fitting what are described as "bronze" through hulls to their latest efforts:

Beneteau Oceanis 30.1 - Yachting Monthly

Better late than never I guess, unless you are stuffed with an older boat.

.

 

[penfold]

When the problem with brass valves being fitted came to light Yachting Monthly were publishing (in June 2011...)

"This is now known
as DZR (dezincification-resistant)
brass and has the EN designation
of CW602N. This material is
proven to be the equal of bronze
in a saltwater environment
and is now in common use.
Unfortunately, the other similarity
it has with bronze is price."

....and there's plenty of sources that say the same thing today so what's the truth?

If people are/were paying bronze money for DZR their pants are/were being pulled down.

 

[Ammonite]

If people are/were paying bronze money for DZR their pants are/were being pulled down.

Yes and no. Back then you couldn't get a lot of fittings in DZR and typically ended up with a mix of DZR, Gun Metal and Bronze if buying via ASAP for example, but saying DZR was the same price as bronze was a bit daft.
Nowadays it's a different story as everything is available in DZR at reasonable, non bronze prices...although apparently you need to now throw this all away if some are to be believed ?

 

[Poey50]

Here's another interesting and misleading snippet from the most recent PBO article in which DZR becomes conflated with brass. On page 63 the author reports (whether accurately or not can't be known) a conversation with James Turner from a distributor called Meridian Zero. This is the complete paragraph ...

"DZR contains 32% zinc and was developed for the domestic plumbing market, but when the RCD came in and boatbuilders realised skin fittings only need only last 5 years, they used it on boats too. 'Whoever thought of that directive was barking mad' said James. "Skin fittings should last 30 years not five. What's more, if you put a boat in a marina with DZR fittings with a lot of stray currents from other boats you can end up with one that lasts 3 years and crumbles in your hands."

All totally misleading and perhaps no surprise that they then decided to go for TruDesign on the project boat. But on second reading I noticed something new. James Turner is, on page 66, now described as James Turner from TruDesign.

Probably a different person with the same name ... coincidences do happen. I'm sure no-one would talk down DZR for commercial purposes, would they?

 

[Buck Turgidson]

What the regulation effectively means is inspection and replacement should be expected for any craft that doesn't specify a longer life for its through hulls.
When a regulator writes a rule like that they take into account that their minimum standard will become a norm for everyone not building to a specifically "quality driven" premium market.
The cost conscious builder stays in business by building a product that meets the magic CE standard and appeals to the market at the lowest production cost possible. So they can price their product in the market at the sweet spot for max profit. If their build cost is higher due to all the unobtanium they have used in the manufacture they need to make that front and centre of their marketing.
As my old friend would say "the whole point of a Doomsday Machine is lost, if you keep it a secret".

As an aside, the first universal agreed aircraft performance requirements were adopted in 1953. Since then all commercial aircraft are designed to meet those 1953 requirements. So your brand new airliner performs no better at take off than a BAC111 or Boeing 727.

 

[Ammonite]

I suspect its unrelated but I've just viewed a FB video extolling the virtues of composite valves (the ones being demonstrated happen to be TruDesign) which is, let's say, less complimentary about DZR valves ;-)