Why oh why did I use some stats with my tongue firmly in my cheek?? CivvyFSO, as I noted in my first ever post on this forum, I was being flippant and stretching statistics.
My overall point is that with regard to shared houses, whether two storey, three storey or even, dare I say it, more storeys, there is no evidence whatsoever to suggest that the occupants of shared houses are at any more risk than those in similar, single occupancy dwellings. Because of my friendly local EHO, I have had to carry out a considerable amount of research into the risk in shared houses (The sort of places where the LACORS guide recommends LD3 for up to four storeys) and there is nothing to suggest that there is any raised risk in these properties. To look at the death and injury data for HMOs and to conclude that all HMOs are dangerous is like looking at fireworks factories and concluding that all factories are dangerous. There is a vast range of risk in HMOs.
If you read the ENTEC report (sadly I have) you will find that it contains no evidence whatsoever to conclude that shared houses of three storeys pose any particular risk. You do have to read the full report to get to the detail. As johno67 (no relation) rightly points out it's not the buildings that pose the risk, it is the occupants.
The Small Landlords Association report referred to by johno67 concluded, as far as I can recall that shared houses are 'stunningly safe' by comparison with all other dwelling types. If my memory serves me correctly it looked at fatalities in London over about 7 years and in those 7 years there were 5 fatalities, among a shared house population of about 500,000 people. One was a murder and two were suicides, so not much that any housing authority inspector could do about those. One was an alcoholic epileptic man who had a fit while drunk and fell on an electric bar fire. Perhaps the safety measure was central heating? The final death was a woman who set fire to her clothing while lighting candles in her room at 4am. I think I recall that she was drunk also. Perhaps she could have been saved, perhaps not.
You could have two absolutely identical buildings next door to each other. One occupied by five young, fit and healthy friends who have chosen to live, cook and eat together for a significant period of time and one occupied by five strangers who regularly move on, are alcohol and drug dependent and live, cook and eat in their own rooms. Which one is the fireworks factory and which one is the small family business making garden gnomes?