Risk levels analyzed in new Swedish building regulations

In the afternoon session yesterday two Swedish fire consultancy companies presented a comparison of risk levels in the old vs. the new regulations. Mainly, the prescribed design parameters, such as the 2 & 10 MW HRR were analyzed. Analyzing risk levels is welcome and there's actually several similar projects going on now in Sweden.

However, some decisions and assumptions were made that may have led to another result.
- Minimum levels are not aspirational, individual practitioners are responsible for choosing a relevant design fire at, or above, the minimum level. Assuming that all consultants choses the lowest safety level is something they are liable for themself.
- Involved companies were not chosen to be statistically representative. Companies on the other ends of the scale may have been excluded. There are examples of design being performed previously where robustness (probably) were not handled at all - whereas the analyses assumes that all companies tested robustness.
- Many data in the analysis were lacking for the Swedish situation and thus data from other sources were used. This introduces uncertainty in the model.
- Difference in the suggested design HRR and the HRR of the consultants is just one factor affecting risk. Other factors, such as fire growth, may have a greater significance.
- A question that was not raised in the presentation is what risk the risk level should be? Could the analyzed values from the consultants have been over-conservative?

The article has great value in starting a discussion, even though no scientifical conclusions may be drawn. It's obvious that there's a great variance in how the previous regulations were applied. Risk levels will now be more conformed with greater societal control.

Further questions must certainly be discussed - what risk level do we get with nationally set values? One question that also is relevant is what the risk level should be? One way would be to compare with the risk levels of prescriptive regulations or with regulations in other countries - and to look more into factors affecting risk levels.

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The Nordic countries are well represented at the conference. There's some 15-20 Swedes of the 160 participants. In the picture you see Swedish and Icelandic representaties - at the table blocking the emergency exit ;)