Dear David,

many thanks for your answer...  a further indication for me that we might have a problem with our fire retardancy tests..

With best regards

Michael

Dear Michael,..

you are absolutely right... we have a real problem in the evaluation of materials under realistic fire conditons. The reality learns us to look deeper.

With best regards

Joachim

Dear "Followers",...

yesterday night I have send to some of you the note, that I have a "complicated" question with no answer from anybody up to now. Sorry I have forgotten to include the link... I got a lot of messages asking for the link. This here is my question,,,see above

With best regards

Michael

Dear Michael. This is absolutely interesting, yet more complicated that it seams at first glance. Thank you for the link.

My belief , in terms of building materials is that local materials are usually more suitable for regional building, because they adapt better to regional climate, in terms of local comfort and health. The same generally applies to local food habits. Ancestral cultural legacies should be respected...

With modern globalisation, humans forget to adapt, regionally. Hence, modern life global threats simply won't adapt either...

This is my personal view of the problem you propose. Please forgive me, if it looks a bit out of context...

Dear all,

from the material side, it is more realistic to look materials (generally polymers) with an intrinsic fire resistance or suppression. In the past there was a big effort to substitute polyurethanes linings in buildings by foamed phenolic resins. I think there was very fruitful results. Other thing one should also take in consideration is the paint formulations: binders, additives, and organic solvent if used. These may be good elements for fire ignition and/or propagation. Regards

Dear @Michael, I am not an expert about the issue you have raised. 

Experts query quality of cladding on Dubai buildings!

"The fires that have erupted in Dubai landmarks have raised concerns about the quality of material used to clad the emirate’s buildings.

After a fire at The Torch in February last year, experts believed that a majority of Dubai’s approximately 250 high-rises use cladding panels with a thermoplastic core for insulation, to improve rigidity and for cosmetic purposes.

Flammable cladding materials, comprising plastic or polyurethane fillings – called a thermoplastic core – sandwiched between aluminium panels, have been blamed for spreading fires at both the Al Baker Tower 4 and the Al Tayer Tower in Sharjah in 2012.

“On some fires that we’ve seen, clearly the facade itself contributed to the way that the flames have spread. But I don’t know if that’s the case with Thursday night’s incident,” said Andy Dean, head of facade engineering for consultancy firm WSP yesterday..."

http://www.thenational.ae/uae/experts-query-quality-of-cladding-on-dubai-buildings

This is very good research question and research paper follows!

Building Facade or Fire Safety Facade!

http://global.ctbuh.org/resources/papers/download/405-building-facade-or-fire-safety-facade.pdf

Well, I guess I have nothing to add here :)  The insulating materials we use nowadays are meant to burn. Their difference to previous (natural inorganic) materials mankind used in facades lies on their very nature, organic. But in a world with 7 billion people, the choice is for the "less bad" material.

Thermal insulaion should also take in to account flame retardancy from electrical fires. Electrical fires have the potential to burn thermal insulations, unless otherwise they are flame retardant up to a certain index. LOI is not the only yardstick. For example, cured epoxies char but do not burn,. Partially cured or incompletely cured epoxies can burn and char in a mixed way. How many use a vinyl ester with bromination and al2 o3 fillers to make it really flame retardant ? Epoxies still rule the world. While a volume of epoxy and hardener are mixed they can catch fire if the exothermic reaction is severe. When you repair a building crack with   epoxy patches, you should be careful about the reactive mass, and do it in installments. By the way, thermoplastics should be avoided in facades and filled inert thermosets can be used as they are meant to be durable and not disposable just like the building. Out gassing due to hygrothermal attack is another issue as methane emissions in a closed room are dangerous as it is self combustible at room temperature when the concentration is fairly high. So we need to add certain fillers to reduce outgassing from structural polymers and paint them with the right paints to be inert, durable and flame retardant.

Thank you

Padmanabhan. k

Hi Colleagues

I don't have a lot experience with these materials, but i dont like the "retardant". i did same essays with retardant flame material and depending on the condition it is not so "retardant". The best material that i know is the oxidized PAN fiber. it is real flame resistant and thermal barrier. But is black (no color change) and expensive in compare with flame resistente material. I have studied the transformation of textile PAN fiber in to oxidized PAN fiber aim activated carbon fiber, Textile PAN is cheap but the methodology to conversion in oxidized form is not so simple.

I hope that contributed with same information  

Dear Padmanabhan, Not sure if your statement "By the way, thermoplastics should be avoided in facades" is 100% correct specially when I look on our Ultem grades performing up to or above 47% LOI and has UL94 V0, V2 and 5VA ratings. Regards,

Dear Michael,

I am not any expert in the field of fire retardants and like... My amateur idea how to avoid fire in the case of facades is use of nowadays applied insulation  boards /shilds/ from pressed fibres of inorganic materials, e.g. from glas fibres or fibres from melted basalt.

Rastislav 

I think the problem comes from interaction! Or more exactly how materials are combined together and the fire event in Dubai's building is an interesting illustration. I don't doubt that civil engineering engineers know the flammability risk of the materials individually but did anyone think about combining materials that may have different behaviour when put together ? To be able to go further, the study of the used materials should be planned…

Hi, here in México we don't use those types of materials....our houses are building with traditional bricks, covered by a mix of portland cement, and finally colored by acrilic paintings. In the case of "modern buildings" (for offices, banks, etc), the construction techniques are simple, we use a lot of concrete for structure covered by glass and aluminum structures....and the fires are rare in buildings....I can't remember a fire in a building in years....

New UAE fire code delayed over Address Downtown Dubai blaze!

"Following the implementation of the nationwide 2012 Fire and Life Safety code, authorities sought to phase out non-fire-rated cladding, consisting of a combustible thermoplastic core sandwiched between aluminium sheets. Concerns about buildings that predate the code remained.

At industry meetings during the run-up to issuing the code, experts suggested fire barriers as a solution for older buildings where owners could not replace all combustible cladding...

Owners must renew a no-objection certificate every year from civil defence following inspections to ensure modifications are fire-safe. This contrasts with the current one-time completion certificate issued after construction.

The manufacturers’ liability will also be outlined. Companies selling building materials not approved by civil defence and municipalities will now be subject to prosecution.

The updated code will also state the final facade product must be tested and consultants will be responsible for the structure for at least a year after project delivery..."

http://www.thenational.ae/uae/new-uae-fire-code-delayed-over-address-downtown-dubai-blaze

Dear David,

I have read in some newspapers, that the building got a new cladding only some years ago. The statement "It is believed to have started on the fourth floor and spread quickly" is a severe indicator that something was wrong with the used materials.

Best regards

Michael