Low level ventilation

[Poppin]

Can anyone clarify bss requirements for low-level ventilation? Can't understand it from the document. Is it required or just reccoemnded to have a certain amount of low level ventilation? Or is it just a certain amount of overall ventilation, with whatever amount of low level ventilation is practicable? The boat builder left me with some unused vents in the shell on the widebeam, and I'm wondering if all of these need to be ducted down to ground level, one in particular would be easier to leave unused. 

[PCSB]

Section 8.9 of the BSS doc applies, specifically 8.9.1

"Is the vessel provided with adequate fixed ventilation?" A/R A = advisory and applies to private craft, R = Requirement and applies to hire boats etc.

[Lady M]

The amount of ventilation required will depend on the equipment installed.  This may explain why your shell builder has provided the potential for more vents.  The BSS examiner usually calculates total ventilation required then applies 50% to each type of ventilation.

[ditchcrawler]

2 hours ago, Poppin said:

Can anyone clarify bss requirements for low-level ventilation? Can't understand it from the document. Is it required or just reccoemnded to have a certain amount of low level ventilation? Or is it just a certain amount of overall ventilation, with whatever amount of low level ventilation is practicable? The boat builder left me with some unused vents in the shell on the widebeam, and I'm wondering if all of these need to be ducted down to ground level, one in particular would be easier to leave unused. 

Its a good idea ducting it as it reduced the force 8 gale that lots of narrowboats have blowing in the front doors and out the back

[Momac]

[magnetman]

Was the OP Boat not a private Boat? 

 

 

 

I've had quite a few Boats and one of them, which was a former restaurant barge, did have very effective low level ventilation. It was quite impressive. 

 

basically weld elbows on the front deck each side ducted down to the 'floor' level then similar vents at the starn end. 

 

I like a bit of air. I know it robs heat from the cabin in winter but the scavenging effect keeps everything clean..

 

None of the other Boats have had ventilation that effective. 

 

 

When the BS scheme started up ventilation was a requirement for all Boats so people had horribly inappropriate holes cut in perfectly nicely made steel doors. Shocking. Then a few yars later they say 'Oh never mind you don't need that'. 

 

Damage already done. 

 

Going back in time I would have hung temporary doors with holes in then put the real ones back on. 

 

Who'd have guessed that of all things on a Boat the ventilation turns out not to be a mandatory requirement in a Safety Test. 

 

 

 

BS by name BS by nature. 

 

Still at least we don't get Boats exploding and killing people every day like in the old days. That's an improvement ! 

[blackrose]

I think overall ventilation should be roughly split between higher and lower level. On a previous BSS test the inspector did the vent calculations and told me I had double the amount of low level ventilation required for my boat. So I reduced it by half. The same guy came back 4 years later, redid the calculation and told me it was fine. As others have said, ventilation is just a BSS advisory now for some odd reason, rather than something the boat's going to fail on.

 

You can do the calculation pretty easily yourself. I think the formula is in the BSS guide, but if the OP isn't going to do that, perhaps you should just leave the vents you have place and then possibly modify them once the inspector has been and gone and you have a better idea of whether you're under or over. Obviously you don't want to be under for safety reasons, but you don't want to be too much over either because that's just a waste of energy in winter.

Edited December 25, 2023 by blackrose

[Jen-in-Wellies]

8 hours ago, blackrose said:

I think overall ventilation should be roughly split between higher and lower level. On a previous BSS test the inspector did the vent calculations and told me I had double the amount of low level ventilation required for my boat. So I reduced it by half. The same guy came back 4 years later, redid the calculation and told me it was fine. As others have said, ventilation is just a BSS advisory now for some odd reason, rather than something the boat's going to fail on.

I had a similar experience. Was advised to take the mesh grills out of the shiny brass things under the mushroom vents, but that was it. They reduce the cross sectional area a lot, but do stop spiders from abseiling in. Mine was a Piper shell, which has low level vents each side of the bow doors, feeding air down to the bilge. Saves the howling draft through door vents that are a feature of many boats.

8 hours ago, blackrose said:

You can do the calculation pretty easily yourself. I think the formula is in the BSS guide, but if the OP isn't going to do that, perhaps you should just leave the vents you have place and then possibly modify them once the inspector has been and gone and you have a better idea of whether you're under or over. Obviously you don't want to be under for safety reasons, but you don't want to be too much over either because that's just a waste of energy in winter.

I was so tempted to reply to the OP with just RTFM when he started the topic. I resisted till now, when there have been some sensible answers first.

[ditchcrawler]

12 hours ago, magnetman said:

Was the OP Boat not a private Boat? 

 

 

 

I've had quite a few Boats and one of them, which was a former restaurant barge, did have very effective low level ventilation. It was quite impressive. 

 

basically weld elbows on the front deck each side ducted down to the 'floor' level then similar vents at the starn end. 

 

I like a bit of air. I know it robs heat from the cabin in winter but the scavenging effect keeps everything clea

Similar to what I have. Box section short mast at the front of the tug deck to carry head light etc, Facing back towards the cabin to shelter from the wind a louver grill to wet air in, down under tug deck and then down to base plate level

[Onewheeler]

None of the four or five examiners who have done our BSC over the years have noticed that the brass louvres on the front bulkhead are fixed to solid sheet steel. They've passed on the basis of the size of the slots in the louvres.

[Alan de Enfield]

53 minutes ago, Onewheeler said:

None of the four or five examiners who have done our BSC over the years have noticed that the brass louvres on the front bulkhead are fixed to solid sheet steel. They've passed on the basis of the size of the slots in the louvres.

 

Knowing the standards of the examiners I have had over the years, nothing surpises me anymore.

'Boatings Shameful Secret'

'Billing Support System'

'British Scamming Survey'

[blackrose]

1 hour ago, Onewheeler said:

None of the four or five examiners who have done our BSC over the years have noticed that the brass louvres on the front bulkhead are fixed to solid sheet steel. They've passed on the basis of the size of the slots in the louvres.

 

Well if you're trying to decieve an inspector I'm sure you can succeed, they're not detectives. It's reasonable to assume that behind a brass grille there's an aperture. What do you want them to do, take the grille off to see what's behind it? Then you'd probably be complaining about overly officious inspectors. They can't win with some people.

Edited December 25, 2023 by blackrose

[Onewheeler]

It took me well over 20 years to realise that they are dummy vents. I don't see why an inspector should notice!

[David Mack]

5 hours ago, Onewheeler said:

It took me well over 20 years to realise that they are dummy vents. I don't see why an inspector should notice!

Did you not notice they were strangely draft-free vents?

[magnetman]

Good BS inspectors will check for this even now that ventilation is not mandatory. Not difficult to see with a torch. 

[Drayke]

Why do they check if its not mandatory?

[blackrose]

4 hours ago, Drayke said:

Why do they check if its not mandatory?

 

So they can give people guidance and an advisory warning if it fails. They know that most people won't do the calculation themselves. Have you ever done it for your boat? I have but I think I'm probably in the minority even on this canal boat enthusiast forum.

 

Given the importance of good ventilation I agree it's odd that the requirements aren't mandatory in the BSS, but despite all the negative comments here they are still actually trying to stop people from dying unnecessarily.

Edited December 26, 2023 by blackrose

[ditchcrawler]

9 hours ago, Drayke said:

Why do they check if its not mandatory?

They even class it as a failure in their statistics even though they issue the BSC when they say how many boats fail the BSS inspection every year 

[Alan de Enfield]

1 hour ago, ditchcrawler said:

They even class it as a failure in their statistics even though they issue the BSC when they say how many boats fail the BSS inspection every year 

 

 

Do you not think that they class it as a failure to make their 'figures' look as of they are achieving something and so justifying their existence.

 

If no boats fail then why would they be needed ?

[Momac]

10 hours ago, Drayke said:

Why do they check if its not mandatory?

To cover their own liability .

[Momac]

1 hour ago, Alan de Enfield said:

 

 

Do you not think that they class it as a failure to make their 'figures' look as of they are achieving something and so justifying their existence.

 

If no boats fail then why would they be needed ?

it is possible for a BSS certificate to be issued even when the boat fails to achieve a pass on some aspects of the BSS standards.

Examples of these are as per the extract below

 

 

[Alan de Enfield]

1 hour ago, MartynG said:

it is possible for a BSS certificate to be issued even when the boat fails to achieve a pass on some aspects of the BSS standards.

Examples of these are as per the extract below

 

 

 

 

I'm sure you have noticed that those examples shown are NOT BSS Failures as they are all advisory.

 

So there are no 'pass or fail' and the BSS must be issiued

[Onewheeler]

17 hours ago, David Mack said:

Did you not notice they were strangely draft-free vents?

Nope, it would be hard to notice against the convection currents from the cold front deck given the layout of the wooden lining to the front.

[Drayke]

On 26/12/2023 at 03:07, blackrose said:

 

So they can give people guidance and an advisory warning if it fails. They know that most people won't do the calculation themselves. Have you ever done it for boat? have but I think I'm probably in the minority even on this canal boat enthusiast forum.

 

Given the importance of good ventilation I agree it's odd that the requirements aren't mandatory in the BSS, but despite all the negative comments here they are still actually trying to stop people from dying unnecessarily.

 

No I haven't and yes I would agree with you that you probably are one of the few that have.

[Momac]

22 hours ago, Alan de Enfield said:

 

 

I'm sure you have noticed that those examples shown are NOT BSS Failures as they are all advisory.

 

So there are no 'pass or fail' and the BSS must be issiued

Yes they advisories 

Please look at the wording. The comments are on items that have not passed .

If something has not passed then its a fail.

So you still get the certificate with a fail if its an advisory matter.