Tuesday 29 November 2022

Post-Grenfell Report: every high-rise residential building should have a bespoke fire evacuation plan, developed in full consideration of the building design, the composition of occupants and crucially, the presence, or indeed absence, of effective compartmentation

 The National Centre for Social Research (NatCen) was commissioned to carry out a ‘rapid evidence review’ on the topic of evacuating high-rise buildings in March 2020. It’s report was published last week. The lack of clear evidence on fire evacuation in tall buildings limits the usefulness of the report.  These are its conclusions, I have highlighted those I think most relevant to Brent. The recommendation that each individual high-rise building should have a bespoke fire evacuation plan is crucial:

 

Overall, the findings of this review show that despite there being a high-volume of research focused on fire evacuation generally, the availability of evidence focused specifically on fire evacuation in high-rise residential settings is significantly limited. Of that which is available the vast majority is international, with only a handful of studies providing UK-based evidence. Furthermore, the quality of studies was mixed, with many based on focused qualitative studies and small-scale quantitative surveys.

 

While this review was conducted to provide comprehensive insight into fire evacuation in UK high-rise residential buildings, it is limited by a paucity of research and an evidence base largely developed in non-UK settings meaning transferability of findings to the UK is unclear. As such, while the findings provide some relevant contextual insight into fire evacuation within high-rise buildings, they do not directly answer the three core research questions central to this review.

 

What are the most effective methods of evacuation from fires in high-rise residential buildings?

 

Considering the limited evidence base within scope of this review, the findings of this review tentatively suggest that, if evacuation is necessary and effective fire safety arrangements such as compartmentation are in place, phased and partial evacuation strategies (in the form of ‘defend-in-place’ and delayed evacuation) are safer than simultaneous evacuation within high-rise residential settings.

 

The evidence also identifies the importance of ‘delayed evacuation’ for those unable to evacuate unassisted, and the necessary requirements to ensure refuge areas are safe and effective. The success of phased or partial evacuation, however, depends on effective compartmentation and communication systems to provide occupants with sufficient and ongoing information.

 

Nonetheless, despite these overarching findings, the body of evidence suggests that no single strategy is universally appropriate for the evacuation of high-rise residential buildings. Instead, every high-rise residential building should have a bespoke fire evacuation plan, developed in full consideration of the building design, the composition of occupants and crucially, the presence, or indeed absence, of effective compartmentation.

 

Synthesis of international modelling and simulation studies suggested that fire safe lifts can reduce overall evacuation time in high-rise buildings. There is however a distinctive lack of UK-specific research on the effectiveness of lifts for fire evacuation within high-rise residential settings. The extent to which this finding can be applied to the UK is therefore unclear.

 

How do occupants make decisions about fire evacuations from high-rise residential buildings?

 

Collectively UK and international evidence suggested occupants do not immediately evacuate upon recognising fire cues, but first check to validate risk, gather belongings and communicate with other residents. Both UK and international studies also suggest occupants of high-rise residential settings are reluctant to use lifts during fire evacuation, which in UK context is in line with the current NFCC ‘stay put’ position statement that in general in the event of an evacuation stairs should always be used rather than a lift (NFCC 2020).

 

This is due to long-standing beliefs that lifts are not safe during a fire, and concerns around safety and delayed evacuation times. Some non-UK evidence suggested occupants of high-rise buildings are more likely to use lifts during fire evacuation if instructed by firefighters. No research on UK occupants’ willingness to use lifts upon firefighter instruction was identified in the review. The extent to which these findings are transferable to UK high-rise residents is therefore unclear.

 

How do firefighters make decisions about evacuating occupants from high-rise residential buildings?

 

This review identified a significant lack of independent peer reviewed academic evidence into how firefighters make decisions regarding the evacuation of occupants from high-rise residential buildings in the event of a fire. Of the limited evidence available, most was international and focused on the decision-making of firefighters in general, rather than specifically in high-rise residential settings.

 

Considering the limited evidence base, the UK and international evidence outlines two main factors that inform firefighter decision-making: pre-determined procedures and previous experience. International evidence also identifies significant amount of information firefighters must assess in their decision-making. This includes specific features of high-rise buildings, and awareness of occupant vulnerabilities and knowledge of occupant adherence to requests to ‘defend-in-place’ or use refuge areas.

 

Future research and evidence gaps

 

While the findings from this review provide some insight into fire evacuation in high-rise residential buildings, the ability to identify the most effective methods of evacuation is limited by a paucity of high-quality research and an evidence base largely developed in non-UK settings. An important contribution of this review is therefore the identification of significant and wide-ranging evidence gaps, which would need to be addressed in order to improve the peer reviewed academic evidence base.

 

These includes research on:

  • comparisons of the effectiveness of different evacuation strategies in UK high-rise residential settings
  • the effectiveness of lifts for fire evacuation within UK high-rise residential settings
  • UK high-rise residents’ willingness to use lifts during fire evacuation upon instruction
  • the effective evacuation of vulnerable groups from UK high-rise, residential settings. This includes residents with reduced cognition, residents with small children, residents with English as an additional language, and residents’ potentially limited knowledge of evacuation procedures, such as those who are short-term, un-tenured or guests
  • firefighters’ decision-making regarding the evacuation of occupants within UK high-rise residential settings

 

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