Surface Spread of Flame : BS 5876 Part B versus BS476 Class 0

[Messy]

I have come across a 40m long basement corridor that has been recently refurbished. Either side of the plaster walls have been completely covered with numerous rectangular panels that have be clad in a hessian looking material for aesthetic reasons. The corridor serves meeting rooms and a small kitchen

I asked the contractors to supply a certificate to determine that the covering conforms to BS476 Class 0 surface spread of flame to conform to B2 of ADB. However, they have
supplied a certificate that refers to  BS 5867: Part 2: 2008  (which relates to curtains, drapes and window blinds)

It goes on to record that the material 'complies with BS 5867: Part 2: 2008 ? Type B? and  that it 'complies with the Type A ignition resistance requirements of BS 5867: Part 2?.



I content that as BS relates to curtains, & the panels are in effect vertically hung material like a curtain, it may well suffice. But does the above standard relate to equivalence to Class 0 BS476?

[kurnal]

I would agree with your concern Messy especially if the panels are continuous and if there is a cavity a continuous cavity behind the frame and what is the construction behind the hessian? Matchboarding is often used for this type of installation, if this is the case there is a risk of rapid fire spread and a much higher heat release over a longer period compared to curtains.
If the panels are separated by a metre or two and if two way travel is available then the comparison with curtains may be more relevant, and better still if there is a cross corridor fire door.

[Fishy]

I have come across a 40m long basement corridor that has been recently refurbished. Either side of the plaster walls have been completely covered with numerous rectangular panels that have be clad in a hessian looking material for aesthetic reasons. The corridor serves meeting rooms and a small kitchen

I asked the contractors to supply a certificate to determine that the covering conforms to BS476 Class 0 surface spread of flame to conform to B2 of ADB. However, they have
supplied a certificate that refers to  BS 5867: Part 2: 2008  (which relates to curtains, drapes and window blinds)

It goes on to record that the material 'complies with BS 5867: Part 2: 2008 ? Type B? and  that it 'complies with the Type A ignition resistance requirements of BS 5867: Part 2?.



I content that as BS relates to curtains, & the panels are in effect vertically hung material like a curtain, it may well suffice. But does the above standard relate to equivalence to Class 0 BS476?

No, they are completely different test regimes & there will be no equivalence between the two.

[Messy]

Thanks you Kurnal & Fishy

Fishy - as there's no equivalence, does this mean that the BS 5876 is more onerous, thereby giving a greater reduction of risk and acceptable as a a control measure standard as good or better than BS 476 Class 0 - or is it the other way around?

In short can BS 5876 materials be used as wall linings instead of 476 Class 0?

My concerns are this is a small section of a very large building with a commercially sized kitchen which opens on to the corridor and the capacity of the adjacent meeting areas is around 70 persons.

Thanks

[Tom Sutton]

As fishy has said there is no comparison you can only use national standards or European standards as defined in ADB vol 1 page 56, but wall coverings and curtains have their own standards. For instance flame application for curtains is 10 seconds and flame propagation is measured vertically. For class O supporting standards the application of a flame is about 1.5 minutes and flame propagation is measured horizontally.

There is no reason why you should not use curtain material on the walls if it is tested to the appropriate standard some time ago a club owner used carpet fully tested to the appropriate standard but stuck it on the walls which resulted in a major loss of life.

There may be an answer, have you consider clear spray or paint that will achieve a class O standard with a company that will provide test certificates, try yahooing it.

[Fishy]

Trying to demonstrate that one reaction-to-fire test is better/worse/equivalent to another is a minefield & it's quite simply better not to try.  They tend to investigate very different aspects of fire performance and each is conceived to deal with a particular 'end use' condition.  You could certainly not say with any degree of confidence that BS 5867 was more onerous that BS 476 Parts 6 and 7 (and bearing in mind these days we really ought to be talking about BS EN 13501-1 Classifications instead).  The fire test data they've submitted is a complete red herring, in my opinion - I'd ignore it.

You can get wallcoverings that have been tested to BS 476 (or BS EN 15102 - see Table 10 in the AD-B) or Classified to BS EN 13501-1, so there's the option to remove & replace.   If they don't want to remove it, you could recommend (or the Client could require) that they mock up some samples & get it tested & Classified to 13501-1 (or tested to BS 476: Parts 6 & 7).  You'll then have an actual test result to base a risk assessment on, rather than having to speculate about what it might do if it were tested.

[Messy]

Thank you for all the advice as these test standards are a particularly weak area in my knowledge

[wee brian]

If you want to dig further, most test labs will do an indicative test for BS 476 - 7 (class 1,2,3 or 4) for a few hundred quid.

Its handy for settling arguments. The EU equivalent is much more expensive.