Heel Test vs ISO12217

Hi,
We are looking to purchase a small GRP coded boat for use as a 12 passenger ferry in the UK for Cat6 waters, classed as "going to sea". The boat we are looking at is just over 6mt, configured as an open boat with Gunwales and no scuppers.

I asked the manufacturer if they had done a heel test on the vessel to allow 12 passengers, they said they had but it had failed the criteria in MGN280 and only managed to meet the criteria for 4 passengers. They then went through the process using ISO 12217 apparently and the calculations came back as allowing 12 passengers. I think they had calculated it using lines plans etc.

Is this possible as my feeling is that if you put 12 passengers on one side the vessel would capsize. I may be wrong.

 

The boat does not have to be wrecked for it to not comply with ISO. That is to say, even if it does not become shipwrecked, it is possible that it does not comply with ISO.

 

The manufacturer states that it does comply with ISO, could it be that it is an erroneous calculation due to the fact that it is near to the 6mt limit for vessels under ISO 12217?

 

ISO 12217 applies also for boats under 6 m.
Something not enough clear is in there.

 

The main reason for the at variance is that ISO limits for compliance (for a simple pax crowding or "offset-load") are much greater than those of MGN 280.
So, the vessel may well comply with ISO..but it will most likely never comply with MGN 280.
Since the simplified method in MGN 280, 11.4.2.1 states max angle of 7 degrees, whereas ISO states, for < 7m as 18.2 degrees....rather a large difference in compliance standards.

 

Thanks for this..are these in the latest 2019/+ version of ISO...or other?

I clearly have a much older version...Seems ISO can't make up its mind, which absolute values to stick with:



Nice to see an endless seesaw of "common" values for compliance from the agency that is setting "common" standards!!

 

No, they're from 2017. I didn't know there was a 2019 version. It seems they're working on the 2022 version, which hasn't been released yet.
With the regulations it is relatively common to find that a boat that complies with an old standard does not comply with the latest version. That is why it is very important, as in everything, not to become obsolete. We can make fatal mistakes.

 

Indeed, that is generally the case.
But when the values for compliance change so much..it becomes bit of a joke. And that is ISO...a joke!

And one should not assume compliance with one (ISO) set of rules means compliance with another set of standards.
ISO is not statutory, it is just...well...a bunch or words that mean very little...no idea why anyone uses them...

MGN 280 is far more consistent and is part of statutory..which is essential for any passenger boat.

 

Well, I'll gladly try to explain it to you. Normally the designer does not choose the regulations that his boat must comply with. These requirements, and many others, are defined in the SOR and the designer must limit himself to fulfilling them as best as possible. Fortunately, more and more, the designer is required to comply with the ISO standards for small craft. These rules are not perfect, far from it (perhaps they are even bad), but that does not mean that the technician who applies them is a worse technician than the one who uses the regulations of a Classification Society.
If you need more explanations, I will try to teach you everything that, within my knowledge, I am capable of. And don't be embarrassed to ask, no one is born knowing.

 

It is a rhetorical question.
I am more than happy to explain to you what rhetorical means…

The designer almost always chooses the regulations. Since the designer, is creating the design for the client. Most clients do not even understand what an SOR is, and the role of the designer is to guide and educate the client with what is and what is not possible given their “basic” requirements of … "I want a boat". The designer creates the specification based upon their design that fulfils the SOR; which may or may not be more than just a few lines of bullet points. The specification outlines what regulations are required…the specification is written by the designer, around the design they have created.

It is rare to meet a client that understands and has a detailed SOR and even rarer where a client details exactly which regulations they want their design to comply with.

NO they are not perfect.
These rules came about after the EU decided long ago to fill the gap between pure leisure craft and commercial, notably those lacking any understanding of statutory regulations. As the leisure market grew in the late 80s and early 90s, it became clear that many vessels were “finding loop holes” in what they should or should not adhere to, in terms of building standards and safety regulations. There were only just basic guidelines for “simple” pleasure craft, which were beginning to be outpaced by the growth in this leisure market. Notably where accidents occurred, the lacking of any kind of safety regulations was being exposed. Statutory authorities lagged behind…and still do.

Take for example an accident that occurred in 2004 in Weymouth Bay in the UK, with a jetski, with the report finally being published. It has now taken almost 20 years to get a update of the rules and regulations for the safety of powered watercraft. The statutory rules update, if you are interested are located HERE> Those in the leisure industry, either making or operating such craft, seem to think such statutory "rules" are not applicable to them, or wish to ignore them. Hence the creation of such rules..to fill the gap that is exposed.

There is no requirement that a boat must comply with ISO regulations. These are ‘considered’ by those in the leisure and very small craft market as all they want to comply with, as well as, most do not understand what and why Class rules are used for either. As they see using Class rules, in the absence of any other means of compliance, as being too expensive overbearing and so wish to use an ‘alternative’ that is “easier” and “cheaper”. But ISO has now grown beyond its initial remit and is cumbersome and has become much worse than what was once considered (by those using ISO) as a waste of time and money – Class rules.
Hence, no idea why anyone uses such pointless overbearing rules... because the missing part of the sentence is (which was left out, as it was rhetorical)....as there are better alternatives.

 

Thanks for your replies guys.

Being a passenger boat, I don't think passengers would be happy at an angle of 22deg as in ISO 12217. I cannot believe that there is so much variation being allowed between the two standards. I currently have a 6mt catamaran that I am using for passengers, restricted to 10, I know which boat I would prefer to be on, it may be that we purchase another cat. Very interesting to read about the development of ISO standards for boats.

AD HOC mentions MGN 280 as being the go to standard ideally as it is part of the statutory regulations. In the recent "Seadogz" court case in the UK, MGN280 was found not to be legally enforceable as it is only guidance notes and they were not "at sea", MSN notices are legally enforceable. However, if a vessel does not follow the MGN280 requirements, the regulating authority will not give the coding certificate. We have vessels in our area "going to sea" with licences issued by the local authority, this is outside their remit under Section 94(4) of the Public Health Acts Amendment Act 1907,yet the MCA seem to be turning a blind eye, all well and good until an accident occurs.

 

Indeed!..and to make matters worse, the angle of compliance has gotten greater over the years from 18 to 22 degrees...shocking!!
Not a good advert for safety!

This is where you getting into the differences between regulations and codes of practice.

As noted above in the jetski incident and others, you can, if you wanted, go out to sea after having a few glasses of wine. There is no regulation that is currently enforceable to prevent the skipper from doing so.
It comes down to CoP...code of practice. MGN does not get into CoP at all. The CoP basically falls under - conduct of operations and safety management, and sadly these are largely self-regulated.

If, for example, if you were using the HSC 2000 code, then you not only must issues a daily sail plan, but must also have a ISM system in place in your operations.
This is ostensibly how you run your vessels and what training is given etc. to the crew and those maintaining the vessel etc...
There is no such thing for vessels using MGN 280..it is all voluntary...which is where Seadogz fell fowl. And as such, how can you enforce a CoP where there is no regulation to say you must do so...??!!

So be careful not to mix up the two very separate issues. MGN is the regulations/rules for compliance of the safety of the vessel to satisfy the port authority.
How you operate, is a totally separate issue and done via a voluntary CoP