More to this story than meets the eye.

References to the titanic tragedy have been quite popular on this platform. The illusory correlation, or common mental error that leads to misguided thinking and misinformation is prevalent in fire safety.

This article is a constructive critique of the recent news piece from Inside Housing, which responded to an open letter to government .

Peter Apps, deputy editor at Inside Housing authored an article entitled "Second staircases are a good idea – the issue is a lack of clarity ". It's easy to see why the general public might support the hypothesis that mandating two stairs is a good idea, and we wholeheartedly agree there is a lack of clarity on what problem the government are trying to solve.

The first point to clarify is that signatories to the letter do not oppose two stairs, or having more than one. The letter signatories oppose making unnecessary prescriptive requirements, that may not achieve a greater level of safety or worse cause unintended consequences.

The signatories call for three things in the letter:

• The decision on whether to provide a second stair in all new buildings to be evidence based with suitable evidence and reasoning explained.
• That there is suitable equitable escape from these buildings.
• That residents of existing single stair buildings are considered.

Background

Many Chartered Engineers that specialise in fire are questioning why a second staircase should be mandatory for all new residential buildings.

There are people on the periphery of the fire safety profession that have stated publicly that our Government should mandate for 'Black swan events as alluded to in this article'. A black swan is an unpredictable event that is beyond what is normally expected of a situation and has potentially severe consequences. Black swan events are characterized by their extreme rarity, severe impact, and the widespread insistence they were obvious in hindsight. Difficult, not impossible to mandate for, but potentially incurring costs in bringing about a reduction in risks that are seriously out of proportion to the benefits achieved e.g. following 9/11 should we mandate that all new buildings over 18m withstand the impact of a Boeing 787-8 Dreamliner? Clearly not. If we could, let alone did, would the public be comfortable paying for it? Or are there other risks (white/grey swans) that are more pressing and existential, such as climate change, that we could and should invest in to mitigate risk?

Whilst 200 or so fire fatalities occurred in England in 2022, to add some perspective there were 4500 heat related deaths caused by existential threat of climate change. There doesn't appear to be much thought about the embodied and operational carbon impact of this decision and we need better material stewardship at all levels, including Government policy.

Addressing the main points in the article.

The author/journalist makes a number of other points which he feels are obvious and I have taken some time to consider them in a systematic analysis and evaluation of this journalistic piece.

Point 1 – Journalist says “It is easy to see why. A single staircase introduces a single point of failure. If it is compromised, there is no safe way out of the building for those who need it".

A single stair building provided with a holistic fire strategy has a multi-layered approach to fire prevention, preparedness, response, and recovery that takes into account various interconnected factors in order to comply with legislation pre and post handover, and pass through numerous approving authorities.

An ordinary person who does not have professional or specialised training in fire safety might see a single stair, as a single point of failure, but not fully appreciate the active and passive protection measures, and fire prevention measures mandated by law, that together form the general fire precautions in place that tackle predictable risks, which fall within the realm of normal probability. ?

The package of fire precautions (prevention & protection)

Let's break down some of the thinking. Fire door failure could be as big an issue in a two stair building as a single stair building.? It might seem like a simple question. How could providing two stairs not be better than having just one stair? There are lots of arguments about redundancy and robustness, options for escape while firefighting operations are under way. But one counter argument is that, if a fire has reached a stage where the containment to the flat of origin has been breached and the smoke control protecting the single stair has failed to cope, then it is possible that whatever has caused the one stair to be compromised will also cause the second stair to suffer the same failure. Two poorly constructed, badly maintained stairs are not likely to provide any greater safety than one correctly constructed and maintained stair, unless separated by some distance from one another, which would not be possible in limited footprint tower blocks.

It's preferable to approach the problem holistically and solve issue with the life safety provision with the redundancy offered by considering the sum of all life safety provisions

Luckily this is how our system currently works and forthcoming changes make it even more robust.

When designing compliant buildings, the functional requirements B1 – B5 of the Building Regulations are considered a package and together achieve an acceptable standard of fire safety.? The core of this principle is the use of multiple layers of safety, with enough redundancy as so be sympathetic to poor management.?

The illustration below sets out how risk is mitigated, from design, through engineering, safety assurance, and risk management then the prescribed fire protection measures (active and passive) complimented by fire prevention i.e. management are there to serve us in the event. The first line of defense i.e. effectiveness of residential sprinklers is well studied. As set out in BS PD 7974 they may work as intended in up to 94% of cases and control or extinguish fires in up to 99% of cases and whilst this is a requirement for all new buildings over 11m in height, it is complimented by another layer of defense, compartmentation which is also there to prevent fire spread.

We are right to have concerns regarding compartmentation, there are many instances of defective fire compartmentation. Awareness of the criticality of fire compartmentation and passive precautions significantly increased in the last twenty years and historical evidence, points to the fact that despite quite often being poorly constructed and maintained this strategy has worked effectively and normally, a fire will burn itself out before spreading to other parts of the building.

In a recent poll 77% of respondents agreed that awareness is increasing . This is positive news for fire safety, but there is still much work to do to ensure appropriate product documentation, field of application, and of course compartmentation breaches do not occur when in-use.

Some draw false equivalence between compartmentation failures and other failures such as the application of highly combustible materials to the exterior of buildings. The latter results in incontrollable, extensive and rapid fire spread, it creates a condition where the race between firefighter and fire is un-winnable. Whereas compartmentation failures result in a much more restricted form of fire and smoke spread. Compartmenting is a strategy that has been adopted since we first started building multi-storey buildings and we do need to be vigilant, but analyses and statistical data do not identify the same scale of hazard or risk arising when compared with highly combustible cladding.

Then there is ventilation to protect the stair and compartmentation around the stair and there is not a Housing Association in the country that has not been undertaking fire risk assessments year after year on the same portfolio of buildings, making incremental improvements along the way.

Coordinated firefighting and emergency egress can still occur on a single stair; one doesn’t have to preclude the other.? The UK has average response times, under 10 minutes and the attending fire service can use the Evacuation Alert System to initiate the evacuation of the floor(s) most in need of evacuation whilst using the fire fighting lift for vertical transport of equipment.?Smoke control measures are there to reduce the risk of smoke entering the stair during fire fighting phase, and being able to clear corridors of smoke once the door to the fire flat has closed. This combined with sprinklers, fire detection and alarm systems, compartmentation offer multiple layers of redundancy into the design even without considering a second stair. Of the 200 or so fatalities that sadly occur most die in their own homes, not the common parts i.e. corridors/stairs.

It is easy to jump to conclusions without sufficient evidence or a complete understanding of a given situation. Only having part of the story might lead to an incorrect correlation that a stair is the single point of failure in the fire strategy and that a full package of fire precautions is not provided in today's modern buildings. Incomparable with Grenfell Tower, which did not comply with the Building Regulations/RRFSO in place at the time and suffered uncontrolled external fire spread.

Point 2 – Journalist says “Our faith in high standards of ‘compartmentation’ – the idea that fire will be restricted to the flat it starts in for at least two hours, meaning it can be safely extinguished without a mass building evacuation. But this was before the Grenfell Tower fire of June 2017”

This is not strictly the case. Walls (a) between adjacent apartments and (b) between apartments and the common corridor, can be 60FR (E, I) in compliance with standard UK guidance.?Furthermore there is no direct correlation between fire resistance periods in a furnace test and real time in a real building fire, especially when fire suppression is provided, e.g. steam temperatures would never cause failure of a 60mins FR compartment wall. Adequate operation of the sprinkler system will either extinguish or likely suppress the fire so as to have little or no significant impact on a 60 minute fire resisting compartment line

The ignition of cladding on the external walls was not a failure of the internal compartmentation really; it was a failure in the external wall design and construction which ultimately caused fire to spread across multiple compartments.

Grenfell was not sprinklered, it did have compartmentation issues but, critically it was clad in an inappropriate material which led to the entire fa?ade being ablaze in the early hours of the morning i.e. the worst possible time.

Most multi-fatality fires have a lot of individual failings which unfortunately come together in a compounding effect and result in tragedy.

It was our national tragedy and make no mistake has led to a watershed moment. Two stairs may not have made a significant difference in this instance, and whilst sprinklers may have extinguished the fire in the room of origin they would not have helped a great deal with external fire spread. As has been evidenced from buildings in the Middle East, China and Australia; sprinklers may mitigate the hazard arising from fire spread over combustible wall materials, but not wholly so.

Compartmentation is a critical component of a 'stay put strategy ' however it is important to note that effective compartmentation is critical regardless of evacuation strategy, and since the introduction of the Regulatory Reform (fire safety) Order 2005 and the fire risk assessment process, it has indeed been evident that poor management can lead to compartmentation breaches.

Competent fire professionals have understood the criticality of compartmentation since post war building studies, and the fact it will only be tested in the event. As discussed already, when installed and maintained correctly compartmentation works, and over the last decade the knowledge, and awareness of the criticality of compartmentation has improved . Nevertheless, our UK fire experience would suggest most fire occurrences are confined to the compartment of fire origin.

Point 3 – Journalist says “Buildings will also stand for more than 100 years. It’s possible that, like at Grenfell, their compliance will be eroded years after construction through poor maintenance or dangerous retrofit”.

The thinking behind this has been drawn from this diagram.

This diagram is a representation of a potential hazardous scenario that could occur when there are significant failings in fire safety management. It is of course 'possible' but hazard potential needs to be complimented by an understanding of likelihood/consequences within a risk assessment. It is a fact that our legislation the RRFSO imposes a duty on responsible persons to take general precautions, undertake suitable and sufficient fire risk assessments and crucially ensure that testing and maintenance happens. This legislation has teeth and enforcement can be severe. During the course of my career we have worked with many organisations that do care about fire safety, are taking it seriously and appoint us to deliver their fire risk assessment program. It is true that most multi-fatality fire's have management failings at their root cause and entirely possible that through wear and tear, throughout a building's lifecycle there will be periods of non-compliance with the standards to which it was built, or the current standards of the day. Our national statistics show a general downward trend in the number of fire related incidents year on year, and the number of fire related fatalities. Whether this is simply due to a decrease in ignition caused by careless disposal of cigarettes', the increase in prevalence of fire alarms and now sprinklers or simply an improvement in the level of fire safety it is clear that the likelihood of fire occurrence, and fire related casualties and fatalities is decreasing. The risk to any individual becoming involved in such an event is still extremely small. To put this in perspective, UK COVID fatalities stand at 229,272 and in the year ending March 2023 there were 192 fatal dwelling fires in a population of 67.62 million.

I doubt there is a Housing Association or Housing provider in the UK that has not been undertaking fire risk assessments regularly on their building portfolios, and not spending a significant sum of money to improve fire safety. The Regulatory Reform (Fire Safety) Order 2005 enacted on the 1st October 2006 has been the subject of at least three reviews and the conclusion is that it's impact has been broadly positive and the number of unsatisfactory audits carried out by fire and rescue services has decreased significantly over the last decade.

Point 4 – Journalist says “As we race ahead with modern construction methods, we also introduce new risks, some of which are known and some of which are not. The country that saw Grenfell happen should not be so quick to rule out the possibility of black swan events in its high-rise building stock”.

Whilst we should rule out, designing for 'black swan events' is neither practical nor proportionate. Especially when a very clear and proven existential threat of climate change is likely to require our finite resources. Governments have a crucial responsibility to make sensible and well-informed decisions that benefit their constituents and the broader society, we should legislate or provide guidance that tackles white/grey swans, which are somewhat predictable, and fall within the realm of normal probability.

Progress and innovation are important to our sector, industry and planet. Modern methods of construction aim to improve construction speed, reduce waste, enhance sustainability, and achieve higher-quality results. What are we actually talking about? Prefabrication and modular construction, off-site construction and innovations in materials, such as engineered wood products, carbon fiber, and high-performance concrete, contribute to more sustainable and resilient construction. These methods can have significant safety benefits, i.e. improvement in quality control. It's easier to install effective passive fire precautions and get compartmentation details right off-site than up a ladder in the rain onsite. In any event they must satisfy the functional requirements of the Building Regulations and adhere to associated guidance, and yet MMC is often treated by some in the fire industry as if it is some sort of witchcraft.

It's not uncommon to hear the old "they don't build em, like they used too' line, and when I was a Building Control Surveyor I would say "no, they don't and that's because of technological advancement". It's called progress and modern methods of construction should not be treated as a social pariah.

Point 5 – Journalist says “this shows a level of naivety. Our system of building control remains flawed, and it is perfectly possible that future buildings may not be compliant with the rules”.

The Building Safety Act, BSR and Gateways are a direct means of combating the failures in the existing Building Control system.? Providing a second stair case should not be a direct response to considered failures of an approvals system.?

Inclusion of a second stair recommendation in guidance should be a response to clear failures in a single stair design condition, which to my mind the UK has not experienced. There has been a global cladding crisis, and the UK Government acted quickly to tackle that problem.

The evolving landscape of Building Regulations in England & Wales since 2017 reflects a commitment to safety, sustainability, and improved living conditions. We have a far more robust system in place and greater focus on quality from all those involved in the process, and there is not a need to mandate a second stair to all new buildings with a full package of fire precautions in place.

Point 6 – Journalist says “Professional bodies representing fire chiefs and architects have lobbied for second stairs, and other experts have spoken in favour of them”.

The original article published by Inside Housing observed that the NFCC supported a single stair approach under the legacy building regulation system in Scotland, but appears to oppose it under the revised system in operation in England, however..

Professional bodies are quite often a 'broad church' and when they speak it is not always the voice of their members. Fire safety engineering is quite a small niche within the built environment professions, Chartered Engineers that specialize in fire safety with a track record in consulting are a minority group, but what is crystal clear, is that the signatories to the letter in question are everyone of them Chartered Professionals with demonstrable experience specifically in fire safety engineering.

Point 7 - Journalist says “They are also commonplace globally – a study of building codes in more than 30 countries”

The countries mentioned may not recommend single stair buildings, importantly a number of these have performance based systems and therefore do not mandate two stairs either. It is important to separate legislation and guidance.

The guidelines present in other countries are based on local fire statistics, local fire service capabilities, and available research in each country. Additionally, they may reflect somewhat arbitrary views of experts within the country in question.

Many countries have longer travel distances than the UK and they may not all mandate sprinklers or benefit from legislation such as the RRFSO, so it is information taken out of context unless there is a proper study undertaken.

If we are to copy what other countries do, then by mandating an extra stair, should we extend travel distances, and dispense with the RRFSO?

What works well in one country may not be suitable for another due to political, economic, social, technological, environmental, social and legal differences. These rather simplistic comparisons should be treated with some caution, before concluding UK fire safety is broken and our nation is some sort of outlier.

In summary

Our Government has an overarching duty to act in our best interests and to ensure the overall well-being, security, and prosperity of the society they govern. They must be supported by sound advisors to make informed and effective decisions. While public opinion is an important factor in democratic governance, there are valid reasons for governments to exercise caution and discretion when considering public sentiment, fueled by misinformation in the media . Transparency is important, which is why we ask for the impact analysis.

Whilst I might take a different position most of the points this inside housing article makes, there is one point on which we agree. There is a lack of clarity on what the Government are trying to achieve with this move and we are yet to see a comprehensive and convincing impact analysis, which considers the potential unintended consequences of this decision. Some shrug their shoulders and say "it's a political decision, triggered by ministerial discomfort, and so don't try and make engineering sense of it".

However, good governance includes openness about decision-making processes, if the Government are making decisions in the name of fire safety, and many leaders in that specific field are questioning the logic. To say there is a lack of clarity is an understatement and on that point we can agree.

Ben Bradford BSc MSc MBA CEng PPCABE FIFireE FRICS

Chief Executive - BB7 Group Limited