How 'Smart' is Wufi Bio?

DavidHughes · Post by **DavidHughes** » Wed Nov 09, 2011 1:18 am -1100

Given that Mold needs specific food, moisture, temperature and light conditions to grow to what extent (apart from setting Lim Class 0, 1 etc.) does WUFI bio take into consideration the materials at the particular point being examined in a construction build up?

For instance will it give a red if there is a timber board like OSB, Amber for plywood (based on the slide showing OSB as being more prone than plywood) and an Green if it is changed to a concrete block...all other things being equal?

Manfred Kehrer · Post by **Manfred Kehrer** » Wed Nov 09, 2011 5:39 am -1100

Beside Lim classes, WUFI Bio does nothing else take into account.

DavidHughes · Post by **DavidHughes** » Wed Nov 09, 2011 5:43 am -1100

Thanks Manfred, like you say easy and complex.

Is there any paper on how to interpret the 'risk' of mold using Wufi Bio based on the type of material

e.g. concrete block red would be a medium risk but on timber a high risk etc.

It is the interpretation of the Wufi Bio output that is difficult.

Thanks again for everything

Manfred Kehrer · Post by **Manfred Kehrer** » Wed Nov 09, 2011 7:51 am -1100

David, this risk difference is implemented by the 2 different LIMs so I think there is nothing else required

Calina Ferraro · Post by **Calina Ferraro** » Wed Nov 09, 2011 5:53 pm -1100

Hi David,

As Manfred said, the Substrate Classes (Class 0,1,2 & K) account for the differences you are talking about between materials. WUFI Bio doesn't do any "smart" or "automatic" interpretation based on the material, it is strictly what substrate class you select that dictates the LIM curve.

For more info, the WUFI Bio help file has a link to the PhD thesis that helped to develop the program. The link is: http://www.wufi.de/ibp/publikationen/di ... tion_e.pdf

It's actually quite a well written thesis and explains LIM curves in a fair bit of detail.

Essentially, every species of mould has a different LIM curve and on top of that they would each have a different curve for each different substrate. What WUFI Bio does is take the LIM curves for all the moulds most likely to grow on building materials and combined them. It has then broadly groups together the different types of substrates based on how easily mould can eat them. Therefore, Substrate Class 2, for example, represents the lowest threshold for all the moulds likely to grow in building based on how well they grow (on average) on biodegradable materials.

Hope that helps!

Christian Bludau · Post by **Christian Bludau** » Wed Nov 09, 2011 10:17 pm -1100

Hey guys,

let me add a simplified description of the substrate groups:

LIM/CLASS 0: optimum substrate (biological full medium, eg. bread, usually not present in building materials)
LIM/CLASS 1: biodegradable substrates (eg. wood, wall paper, dirty surfaces...)
LIM/CLASS 2: non biodegradable substrates (eg. mineral building materials)
CLASS K: Generalized isopleth system for mycelium growth combining mould species discussed as a possible health risk.

Please see also the help file of WUFI Bio, there is a good description in there.

Best regards,
Christian