Construction Organizations

England’s 2017 Grenfell Tower Fire – Never Again Elsewhere ??

2018-06-12 …

As we approach the First Anniversary of the Grenfell Tower Fire Tragedy, in England, on 14 June … a few days ago, on 4 June 2018, the first batch of Grenfell Expert Witness Reports were uploaded (https://www.bbc.com/news/uk-44356660) to the Grenfell Tower Inquiry Website (https://www.grenfelltowerinquiry.org.uk/) for public view.

At this time, in London … multiple, fragmented investigations are taking place into the actual fire incident … the role of the Local Authority, and building management … those involved in the refurbishment (‘tarting up’) design and construction … the fire services, particularly their ‘Stay Put’ Policy and how it adversely impacted on vulnerable Tower occupants during the emergency … and the highly flawed regulatory model of Building and Fire Codes with light-touch Control, which is still operating in England.  One of Murphy’s Laws immediately springs to mind with regard to the intended ineffectiveness of this overly-complex process !

Colour photograph showing Grenfell Tower in the background … undergoing an almost complete ‘cover-up’ … with, in the foreground, mementos of the Fire Tragedy fixed to railings by local residents. Click to enlarge. Photograph taken by CJ Walsh. 2018-04-29.

Many other countries have adopted some or all of this modern English regulatory model which, after the repeal of an older Bye-Law format, has been shaped by political expediency, cost-effectiveness and general ineptitude … with little or no adaptation to local conditions in the adopting jurisdictions.  Ireland adopted this model with some, but not a lot, of adaptation.

Fire Safety In Ireland ?

On 6 June 2018 … while that investigative activity was hitting the headlines in England … Minister Eoghan Murphy, T.D., Ireland’s Minister for Housing, Planning and Local Government, quietly published the Report: ‘Fire Safety in Ireland’http://www.housing.gov.ie/local-government/fire-and-emergency-management/fire-safety/eoghan-murphy-publishes-report-fire … by a High-Level Task Force within his Department’s National Directorate for Fire and Emergency Management, after serious concerns and fears had been expressed in the public media that a similar fire tragedy might also occur in this jurisdiction.

To be crystal clear … this Report is a Bureaucratic Whitewash … an insult to the Public !  Nice sounding technical ‘blarney’ camouflages a failure to deal directly with critical issues, and answer concerns … while other important issues are avoided altogether.

.May 2018 – Ireland’s Department of Housing, Planning & Local Government Report

Fire Safety In Ireland    (PDF File, 2.55 MB)

Expanding on my comments in the Interview with Barry Lenihan, on RTE Radio 1’s Drive Time early evening news programme on Friday (2018-06-08) …

A.  Initially, Irish Local Authorities were requested to carry out a preliminary survey to identify all buildings of more than six storeys, or 18m in height.  Specifically, they were asked to identify those buildings which had an external cladding system which might be a cause for concern.

This height threshold of six storeys/18m is arbitrary … an external cladding system can be just as much a cause for concern in a building which is lower.  Imagine discarded cigarette butts or a rubbish fire at the base of such a system … and the resulting speed of fire spread and development across a building façade !

B.  The highly flawed regulatory model of Building and Fire Codes, with light-touch Control, which resulted in the Grenfell Tower Fire Tragedy … we also have.  Wake up and smell the coffee Ireland !

At the beginning of the 1990’s, when Ireland had been persuaded by the European Commission to finally introduce legal, national building regulations having a functional format … our National Authority Having Jurisdiction, in desperation, grabbed the then Approved Documents for England & Wales … brought them back to Ireland, put Irish covers on them, and originally called them ‘Technical Documents’ … but, after seeing a tiny ray of inspiring light, later changed their title to the more accurate ‘Technical Guidance Documents’ !  This hunger for adopting all things English which are fire safety related continues to this day … with a similar, ongoing division of Technical Guidance Document B: ‘Fire Safety’ into 2 Separate Volumes.

This may have been a convenient response under pressure … but it has been very short-sighted.  It has impeded the growth of a comprehensive and coherent philosophy on Safe, Inclusive, Age-Friendly, Resilient, Sustainable Planning, Design and Construction Codes/Controls which is suited to an Irish context and responsible local needs (not desires!).

C.  Everywhere … this Report has a lot – too much – to say about Fire Risk Assessment !  After the Grenfell Tower Fire, however, Fire Risk Assessments must only be carried out by competent persons … and the process of Fire Risk Assessment, itself, must be radically improved !  And of course, prior to any Risk Assessment … a proper Fire Hazard Appraisal must be carried out.

D.  To accurately present Fire Safety Trends in Ireland … it is not enough to furnish reliable fire fatality statistics.  It is also necessary to produce reliable fire injury statistics … and reliable information on direct/indirect socio-economic losses.

E.  The quality of fire safety related construction on Irish Building Sites continues to be very poor and problematic.  Fire Compartmentation is nowhere near being adequately – never mind acceptably – reliable !  And during the last few years we have had quite a number of close-calls concerning fire incidents in medium-rise residential buildings.

F.  Fire Evacuation for people with activity limitations is still handled atrociously in our current building regulations.  This is ironic because, on 20 March 2018 last, Ireland had to be dragged screaming to ratify the U.N. 2006 Convention on the Rights of Persons with Disabilities (CRPD) !

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Positive Progress By Another Path !

1.  Abandon the outdated English functional requirements in THEIR building regulations … and adopt a far better, more up-to-date body of functional requirements which is already on the Irish Statute Books … Annex I of the European Union’s Construction Products Regulation 305/2011.  And because there are important horizontal linkages between requirements … immediately finish the ridiculous current separation between Fire Safety requirements and all of the other requirements.  And yes … new Technical Guidance Documents will have to be drafted.

.Regulation (EU) No 305/2011 of the European Parliament and of the Council, of 9 March 2011, laying down harmonized conditions for the marketing of construction products and repealing Council Directive 89/106/EEC

EU Regulation 305/2011 – Construction Products.  See Annex I

(PDF File, 998 Kb)

2.  Yes … ‘Persons Having Control’ of buildings have responsibilities with regard to fire safety.  But that is only one side of the coin !  National and Local Authorities Having Jurisdiction have greater responsibilities.

If we are at all serious about Consumer Protection … bad, inadequate, faulty construction must be prevented beforehand … it is too late, too costly and, in many cases, too impractical to correct afterwards.  Self Regulation by building design professions and construction organizations is NO Regulation !  Stringent, independent technical control inspections must be carried out on all projects by Building Control personnel … which used to happen in Dublin City/County and Cork City/County prior to the introduction of legal building regulations in the early 1990’s … and, depending on complexity, must also be carried out at critical stages during the construction process.

Building Control Sections in all Local Authorities must be properly resourced with competent personnel, equipment, training and support infrastructure.

Inspections concerning compliance with all functional requirements in the building regulations, including fire safety, must be carried out only by Building Control Personnel.  Chief Fire Officers must not be allowed to manage or be involved in any aspect of Building Control.  On the same project … a Disability Access Certificate Application and a Fire Safety Certificate Application must be inter-linked and overlap sufficiently, showing no gaps in compliance.  Inspections must be carried out in connection with all Certificate Applications.  Building Control personnel must satisfy themselves that actual construction at least matches, if not improves upon, what is shown in design documentation.

Building Control Inspection Reports must be made available for public view.

3.  Firefighters are NOT a disposable Social Asset !  National and Local Authorities Having Jurisdiction … and some Chief Fire Officers … must begin to understand this fundamental truth !

Fire Services in all Local Authorities must each be properly resourced according to local needs … with competent personnel, equipment, training and support infrastructure.  Shared provision of resources looks very neat on paper but, in practice, works very badly.  Refer to the Grenfell Tower Fire and London Fire Brigade having to borrow firefighting equipment from other Fire Services.

After the 2015 Tianjin Regional Fire Devastation, in China, and the 2001 WTC Attacks on 9-11, in New York City … front line firefighters must be supported by Specialist Hazard Appraisal and Structural Engineering Units.

For Firefighter Safety in buildings and to quickly find people with activity limitations waiting in Areas of Rescue Assistance and/or other survivors in different locations … a portable and reliable Thermal Imaging Camera is an essential piece of every firefighter’s equipment.

And Firefighter Safety begins with good building design.  In all but the most simple building types, Circulation Routes must be designed for Contraflow … people moving away from a fire in a building and towards safety while, at the same time, heavily equipped firefighters are entering the building and moving towards the fire.

Colour photograph showing Contraflow on a building staircase … people moving down a staircase away from a fire and towards safety while, at the same time, heavily equipped firefighters are moving up the staircase towards the fire. Click to enlarge.

There is no place for ‘Stay Put’ Policies in Irish Residential Buildings of any height.

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Ireland’s 2017 Oireachtas Report: ‘Safe As Houses’ …

December 2017 – Houses of the Oireachtas – Joint Committee on Housing, Planning & Local Government

Safe As Houses ?  A Report On Building Standards, Building Controls & Consumer Protection

(PDF File, 1.01 MB)

This was a good effort by our public representatives … but they missed core issues !

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After The Grenfell Tower Fire !

Further to my last Blog, dated 2017-10-10 …

The 2017 Fire in England was not an extraordinary fire.  Since the beginning of this decade, we continue to see a series of such fires: South Korea (2010) – UAE & France (2012) – Chechnya (2013) -Australia (2014) – UAE, Azerbaijan & UAE again (2015) – UAE (2016) – UAE & Russia (2017) – Turkey (2018).

With regard to Command & Control of Large Scale Emergencies … English AHJ’s should have paid attention to the 2005 & 2008 U.S. National Institute of Science & Technology (NIST) Recommendations following the 9-11 WTC Buildings 1, 2 & 7 Collapses.

The Fire Safety Objectives in current Building & Fire Codes/Regulations are very limited.  In Ireland, this is clearly stated in Technical Guidance Document B …

‘ Building Regulations are made for specific purposes.  Part B of the Second Schedule to the Building Regulations is therefore primarily concerned with the health, safety and welfare of persons.  The fire safety measures outlined in this guidance document are intended for the protection of life from fire.’

Only insofar as it is necessary to protect the lives of able-bodied building users/occupants … is there a concern for property protection.

There is only inadequate, token concern for the protection of people with disabilities.

Client organizations, facility managers, building designers, construction organizations … and journalists … must fully comprehend these limits.

In the photograph below … look closely at the External Firefighting Operations at the bottom of the Tower.  There are limits to what can be achieved from outside a building !

Colour photograph showing the developed fire at Grenfell Tower, in London. At the bottom of the Tower, external firefighting operations can be viewed. Click to enlarge.

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  • A Fire Suppression System (Water Sprinklers/Mist/Hybrid) is an essential Fire Protection Measure in ALL Medium and High-Rise Residential Buildings … which include Apartment Blocks, Hotels, Hostels, Student Accommodation & Social Housing, i.e. ANYWHERE there is a Sleeping Hazard.

 

  • A Reliable and Credible Fire Detection & Warning System is an essential Fire Protection Measure in ALL Buildings … and must be capable, under the control of Building Management, of transmitting warnings in many formats, i.e. Audible + Visual + Multi-Lingual Voice + Tactile.

 

  • Fire Evacuation Routes in Buildings must be designed for CONTRAFLOW … people moving away from a fire and towards safety while, at the same time, heavily equipped firefighters are entering the building and moving towards the fire.

 

  • Good Fire Evacuation Route Design is INTUITIVE and OBVIOUS.  In many buildings, however, this is not always the reality.  Effective Fire Evacuation Signage … comprising high-level signage, low-level signage, with both supplemented by photoluminescence … must be installed in ALL Buildings.

 

  • For the purpose of protecting Vulnerable Building Users in Fire Emergencies, ALL Lifts/Elevators in Buildings must be capable of being used for Evacuation.

 

  • Fire Risk Assessments must NO LONGER be carried out by people WITHOUT COMPETENCE in Fire Engineering AND Building Design & Construction … and the Fire Risk Assessment Process itself must be thoroughly re-examined and upgraded.

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END

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Conventional Structural Fire Engineering Design – How Flawed ?

2012-05-18:  Déjà-vu …

” In the early hours of the morning of Saturday, 14th February 1981, a disastrous fire swept through a building called the Stardust in the North Dublin suburb of Artane during the course of a St. Valentine’s Night ‘disco’ dance.  Forty eight people were killed and one hundred and twenty eight seriously injured.  The overwhelming majority of the victims were young people. “

‘Introduction’, Report of the Tribunal of Inquiry on the Fire at the Stardust, Artane, Dublin, on the 14th February 1981.  Report dated 30 June 1982.

As a young architect in private practice … I witnessed, at first hand, the Dublin Fire ‘Establishment’ disappear from public view, without trace, after the Stardust Fire Tragedy.  It was almost impossible, for at least a year afterwards, to have a meeting with any Fire Prevention Officer in the Dublin Fire Authority.  This was a very valuable lesson.

Later, following the publication of the Stardust Tribunal Report … were its Recommendations implemented … with urgency … and conscientiously ?   No way.  For example, it was more than ten years after the Stardust Fire before an inadequate system of legal National Building Regulations was introduced in Ireland.  And to this day, the system of AHJ monitoring of construction quality, throughout the country, is weak and ineffective … lacking both competent personnel and resources !

The proof of the pudding is in the eating … and one of the results, also in Dublin, has been last year’s debacle at the Priory Hall Apartment Complex … where all of the residents had to leave their expensive apartments for fire safety (and many other) reasons.  The tip of a very large iceberg.  See my post, dated 18 October 2011 .

And this is where the problems usually begin …

” There has been a tendency among students of architecture and engineering to regard fire safety as simply a question of knowing what is required in terms of compliance with the regulations.  The recommendation of the Tribunal of Enquiry into the Summerland Disaster that those responsible for the design of buildings should treat fire safety as an integral part of the design concept itself, has not yet been reflected in the approach to the subject at university level.  There is still clearly a need for a new approach to the structuring of such courses which will in time bring to an end the attitude of mind, too prevalent at the moment, that compliance with fire safety requirements is something that can be dealt with outside the context of the overall design of the building. “

‘Chapter 9 – Conclusions & Recommendations’, Report of the Tribunal of Inquiry on the Fire at the Stardust, Artane, Dublin, on the 14th February 1981.  Report dated 30 June 1982.

This Recommendation has still not been implemented … and note the reference to the earlier fire at the Summerland Leisure Centre in 1973, on the Isle of Man, when 50 people were killed and 80 seriously injured.

Today … the same attitude of mind, described so well above, stubbornly persists in all sectors, and in all disciplines, of the International Construction Industry … even within ISO Technical Committee 92: ‘Fire Safety’ !

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Which brings me, neatly, to the recent question posed by Mr. Glenn Horton on the Society of Fire Protection Engineers (SFPE-USA) Page of LinkedIn ( http://www.linkedin.com/groups?gid=96627 ).   As usual, the shortest questions can prove to be the most difficult to answer …

” Can you expand on, or point to where anyone has discussed, the ‘very flawed design approach’ please ? “

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ESSENTIAL PRELIMINARIES …

     1.  Foundation Documents

I am assuming that ‘people-who-need-to know’, at international level, are familiar with the Recommendations contained in these 2 Reports …

  • NIST (National Institute of Standards and Technology).  September 2005.  Federal Building and Fire Safety Investigation of the World Trade Center Disaster: Final Report on the Collapse of the World Trade Center Towers.  NIST NCSTAR 1   Gaithersburg, MD, USA ;

and

  • NIST (National Institute of Standards and Technology).  August 2008.  Federal Building and Fire Safety Investigation of the World Trade Center Disaster: Final Report on the Collapse of World Trade Center Building 7.  NIST NCSTAR 1A   Gaithersburg, MD, USA ;

… and the contents of the CIB W14 Research WG IV Reflection Document … which, together with its 2 Appendices, can be downloaded from this webpage … https://cjwalsh.ie/progressive-collapse-fire/ … under the section headed: ‘April 2012’.

However … I am utterly dismayed by the number of ‘people-who-need-to know’ … who do not know … and have never even bothered to dip into the 2 NIST Reports … or the many long-term Post 9-11 Health Studies on Survivors which have already revealed much priceless ‘real’ information about the short and medium term adverse impacts on human health caused by fire !

CIB W14 Research Working Group IV would again strongly caution that Fire-Induced Progressive Damage and Disproportionate Damage are fundamental concepts to be applied in the structural design of all building types.

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     2.  Technical Terminology

While attending the ISO TC92 Meetings in Thessaloniki, during the last week of April 2012, I noticed not just one reference to ‘fire doors’ in a Draft ISO Fire Standard … but many.  It surprised me, since I thought this issue had been successfully resolved, at ISO level, many years ago.  There is no such thing as a ‘fire door’ … and the careless referencing of such an object, which has no meaning, in building codes and standards has caused countless problems on real construction sites during the last 20-30 years.

Please follow this line of thought …

Fire Resistance:  The inherent capability of a building assembly, or an element of construction, to resist the passage of heat, smoke and flame for a specified time during a fire.

Doorset:  A building component consisting of a fixed part (the door frame), one or more movable parts (the door leaves), and their hardware, the function of which is to allow, or to prevent, access and egress.

[Commentary: A doorset may also include a door saddle / sill / threshold.]

Fire Resisting Doorset / Shutter Assembly:  A doorset / shutter assembly, properly installed or mounted on site, the function of which is to resist the passage of heat, smoke and flame for a specified time during a fire.

… and so we arrive at the correct term … Fire Resisting Doorset … which, as an added bonus, also alerts building designers, construction organizations, and even AHJ inspectors, to the fact that there is more involved here than merely a door leaf.

Now then, I wonder … how, in any sane and rational world, can the term Fire Resistance be used in relation to structural performance during a fire, and the cooling-phase afterwards ?   Yet, this is exactly what I read in the building codes of many different jurisdictions.  Do people understand what is actually going on ?   Or, is the language of Conventional Fire Engineering so illogical and opaque that it is nearly impossible to understand ?

And … if this problem exists within the International Fire Science & Engineering Community … how is it possible to communicate effectively with other design disciplines at any stage during real construction projects.  The artificial environments found in academia are not my immediate concern.

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     3.  Fire Research & Development outside CIB W14 & ISO TC92

In 2012 … there is something very wrong when you have to struggle to persuade a group of people who are developing an ISO Standard on Design Fire Scenarios … that they must consider Environmental Impact as one of the major consequences of a fire to be minimized … along with ‘property losses’ and ‘occupant impact’.  This is no longer an option.

Environmental Impact:  Any effect caused by a given activity on the environment, including human health, safety and welfare, flora, fauna, soil, air, water, and especially representative samples of natural ecosystems, climate, landscape and historical monuments or other physical structures, or the interactions among these factors; it also includes effects on accessibility, cultural heritage or socio-economic conditions resulting from alterations to those factors.

So … how timely, and relevant to practitioners, are ISO Fire Standards ?   Perhaps … obsolete at publication … and not very ??

And … there is lot more to the Built Environment than buildings …

Built Environment:  Anywhere there is, or has been, a man-made or wrought (worked) intervention in the natural environment, e.g. cities, towns, villages, rural settlements, service utilities, transport systems, roads, bridges, tunnels, and cultivated lands, lakes, rivers, coasts, and seas, etc … including the virtual environment.

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We should be very conscious that valuable fire-related research takes place outside, and unrelated to, the established fire engineering groupings of CIB W14 & ISO TC92.  But I am curious as to why this research is not properly acknowledged by, or encouraged and fostered within, the ‘system’ ?

Example A:  Responding to Recommendation 18 in the 2005 NIST WTC Report … a Multi-Disciplinary Design Team published an article in the magazine Bâtiment et Sécurité (October 2005) on The PolyCentric Tower.  I very much enjoy giving practitioners a small flavour of this work, whenever I make presentations at conferences and workshops …

Colour image, from one of my Overhead Presentations ... showing The PolyCentric Tower (2005), developed by a French Multi-Disciplinary Design Team in response to Recommendation 18 in the 2005 NIST WTC Report. Click to enlarge.

Colour image, from one of my Overhead Presentations ... showing The PolyCentric Tower (2005), developed by a French Multi-Disciplinary Design Team in response to Recommendation 18 in the 2005 NIST WTC Report. Click to enlarge.

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Example B:  In spite of a less than helpful submission (to put it mildly) from ISO TC92 Sub-Committee 4 … ISO 21542: ‘Building Construction – Accessibility & Usability of the Built Environment’ was finally published in December 2011 … but it was developed by a Sub-Committee of ISO TC59: ‘Buildings & Civil Engineering Works’

Colour image, from one of my Overhead Presentations ... showing the design of a notional Fire Evacuation Staircase, with an adjoining Area of Rescue Assistance, which responds directly to the 2005 NIST WTC Recommendations. See Figure 62 in ISO 21542:2011. Click to enlarge.

Colour image, from one of my Overhead Presentations ... showing the design of a notional Fire Evacuation Staircase, with an adjoining Area of Rescue Assistance, which responds directly to the 2005 NIST WTC Recommendations. See Figure 62 in ISO 21542:2011. Click to enlarge.

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With the involvement and support of ISO Technical Committee 178: ‘Lifts, Elevators & Moving Walks’ during its long gestation … ISO 21542 is now able to indicate that all lifts/elevators in a building should be capable of being used for evacuation in the event of a fire.  This is already a design feature in a small number of completed Tall Building Projects.  Once more, this is no longer an option.

In addition … if a Fire Evacuation Staircase has a minimum unobstructed width of 1.5 m (from edge of handrail on one side of the staircase to edge of handrail on the opposite side) … this will be sufficient to facilitate the following tasks …

  • Assisted Evacuation by others, or Rescue by Firefighters, for those building users who cannot independently evacuate the building, e.g. people with activity limitations … shown above, on the right, is assistance being given by three people (one at each side, with one behind) to a person occupying a manual wheelchair ;
  • Contraflow Circulation … emergency access by firefighters entering a building and moving towards a fire, while people are still evacuating from the building to a ‘place of safety’ remote from the building … shown above, bottom left, is how not to design an evacuation staircase (!) ;
  • Stretcher Lifting … lifting a mobility-impaired person, who may be conscious or unconscious, on a stretcher ;
  • Firefighter Removal & Contraflow … shown above, top left, is removal of a firefighter from a building by colleagues in the event of injury, impairment, or a fire event induced health condition … while other firefighters may still be moving towards the fire.

Note that in a Fire Evacuation Staircase … all Handrails are continuous … each Stair Riser is a consistent 150 mm high … each Stair Tread/Going is a consistent 300 mm deep … and there are No Projecting Stair Nosings.

Most importantly … in order to assign sufficient building user space in the design of an Area of Rescue Assistance … ISO 21542 also provides the following Key Performance Indicator … just one aspect of a ‘maximum credible user scenario’ …

10% of people using a building (including visitors) have an impairment, which may be visual or hearing, mental, cognitive or psychological, or may be related to physical function, with some impairments not being identifiable.

Is There Any Connection Between Examples A & B ?   There is, and it is a connection which is critical for public safety.  The following Performance Indicator illustrates the point …

Innovative Structural Design – Perimeter Core Location – Design for Fire Evacuation – Evacuation for All

” A Building must not only remain Structurally Stable during a fire event, it must remain Serviceable for a period of time which facilitates:

  • Rescue by Firefighters of people with activity limitations waiting in areas of rescue assistance ;
  • Movement of the firefighters and those people with activity limitations, via safe and accessible routes, to Places of Safety remote from the building ;
  • With an assurance of Health, Safety & Welfare during the course of this process of Assisted Evacuation. “

[Refer also to the Basic Requirements for Construction Works in Annex I of the European Union’s Construction Product Regulation 305/2011 – included as Appendix II of the CIB W14 WG IV Reflection Document.  Are the Basic Requirements being interpreted properly … or even adequately ??]

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ANSWERS TO THE QUESTION …

The Greek Paper is included as Appendix I of CIB W14 WG IV Reflection Document … in order to show that Fire-Induced Progressive Damage is also an issue in buildings with a reinforced concrete frame structure.  It is more straightforward, here, to concentrate on buildings with a steel frame structure.

a)  Use of ‘Fire Resistance'(?) Tables for Structural Elements

We should all be familiar with these sorts of Tables.  The information they contain is generated from this type of standard test configuration in a fire test laboratory …

… and this sort of criterion for ‘loadbearing horizontal elements’ in a fire test standard …

A single isolated loaded steel beam, simply supported, is being tested.  As deflection is the only type of deformation being observed and measured … the critical temperature of the steel, i.e. the point when material strength begins to fail rapidly and the rate of beam deflection increases dramatically … is the sole focus for all stakeholders.

Using these Tables, it is very difficult to escape the conclusion that we are merely interior decorators … applying flimsy thermal insulation products to some steel structural elements (not all !) … according to an old, too narrowly focused, almost static (‘cold form’) recipe, which has little to do with how today’s real buildings react to real fires !

This ‘non-design’ approach is entirely inadequate.

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With regard to the use of these Tables in Ireland’s Building Regulations (Technical Guidance Document B), I recently submitted the comments below to the relevant Irish AHJ.  These same comments could just as easily apply to the use of similar Tables in the Building Regulations for England & Wales (Approved Document B) …

” You should be aware that Table A1 and Table A2 are only appropriate for use by designers in the case of single, isolated steel structural elements.

In steel structural frame systems, no consideration is given in the Tables to adequate fire protection of connections … or limiting the thermal expansion (and other types of deformation) in fire of steel structural elements … in order to reduce the adverse effects of one element’s behaviour on the rest of the frame and/or adjoining non-loadbearing fire resisting elements of construction.

In the case of steel structural frame systems, therefore, the minimum fire protection to be afforded to ALL steel structural elements, including connections, should be 2 Hours.  Connections should also be designed and constructed to be sufficiently robust during the course of a fire incident.  This one small revision will contribute greatly towards preventing Fire-Induced Progressive Damage in buildings … a related, but different, structural concept to Disproportionate Damage

Disproportionate Damage

The failure of a building’s structural system  (i) remote from the scene of an isolated overloading action;  and (ii) to an extent which is not in reasonable proportion to that action.

Fire-Induced Progressive Damage

The sequential growth and intensification of structural deformation and displacement, beyond fire engineering design parameters, and the eventual failure of elements of construction in a building – during a fire and the ‘cooling phase’ afterwards – which, if unchecked, will result in disproportionate damage, and may lead to total building collapse.

Coming from this background and heritage … it is very difficult to communicate with mainstream, ambient structural engineers who are speaking the language of structural reliability, limit state design and serviceability limit states.

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b)  NIST Report: ‘Best Practice Guidelines for Structural Fire Resistance Design of Concrete and Steel Buildings’ (NISTIR 7563 – February 2009)

At the end of Page 18 in NISTIR 7563 …

2.7.2 Multi-Storey Frame Buildings

In recent years, the fire performance of large-frame structures has been shown in some instances to be better than the fire resistance of the individual structural elements (Moore and Lennon 1997).  These observations have been supported by extensive computer analyses, including Franssen, Schleich, and Cajot (1995) who showed that, when axial restraint from thermal expansion of the members is included in the analysis of a frame building, the behaviour is different from that of the column and beam analyzed separately.

A large series of full-scale fire tests was carried out between 1994 and 1996 in the Cardington Laboratory of the Building Research Establishment in England.  A full-size eight-storey steel building was constructed with composite reinforced concrete slabs on exposed metal decking, supported on steel beams with no applied fire protection other than a suspended ceiling in some tests.  The steel columns were fire-protected.  A number of fire tests were carried out on parts of one floor of the building, resulting in steel beam temperatures up to 1000 °C, leading to deflections up to 600 mm but no collapse and generally no integrity failures (Martin and Moore 1997). “

Those were Experimental Fire Tests at Cardington, not Real Fires … on ‘Engineered’ Test Constructions, not Real Buildings !!   And … incredibly, for a 2009 document … there is no mention at all of World Trade Center Buildings 1, 2 or 7 !?!   Where did they disappear to, I wonder ?   Too hot to handle ???

Computer Model Verification and Validation (V&V) are very problematic issues within the International Fire Science and Engineering Community.  The expected outcome of a Model V&V Process, however, is a quantified level of agreement between experimental data (and, if available, real data) and model prediction … as well as the predictive accuracy of the model.

Now … please meditate carefully on the following …

” NCSTAR 1A (2008)  Recommendation D   [See also NCSTAR 1 (2005)  Recommendation 5)

NIST recommends that the technical basis for the century-old standard for fire resistance testing of components, assemblies and systems be improved through a national effort.  Necessary guidance also should be developed for extrapolating the results of tested assemblies to prototypical building systems.  A key step in fulfilling this Recommendation is to establish a capability for studying and testing components, assemblies, and systems under realistic fire and load conditions.

Of particular concern is that the Standard Fire Resistance Test does not adequately capture important thermally-induced interactions between structural sub-systems, elements, and connections that are critical to structural integrity.  System-level interactions, especially due to thermal expansion, are not considered in the standard test method since columns, girders, and floor sub-assemblies are tested separately.  Also, the performance of connections under both gravity and thermal effects is not considered.  The United States currently does not have the capability for studying and testing these important fire-induced phenomena critical to structural safety.

Relevance to WTC 7:  The floor systems failed in WTC 7 at shorter fire exposure times than the specified fire rating (two hours) and at lower temperatures because thermal effects within the structural system, especially thermal expansion, were not considered in setting the endpoint criteria when using the ASTM E 110 or equivalent testing standard.  The structural breakdowns that led to the initiating event, and the eventual collapse of WTC 7, occurred at temperatures that were hundreds of degrees below the criteria that determine structural fire resistance ratings. “

The design approach outlined in NISTIR 7563 is not only very flawed … it lacks any validity … because very relevant and important real fire data has been totally ignored.  The Cardington Experimental Fires were not all that they seemed.

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c)  Current ISO TC92 International Case Study Comparison

Structural Fire Engineering Design of an Airport Terminal Building serving the Capital City of a large country (which shall remain nameless) … constructed using Portal Steel Frames …

My first concern is that the Structural Fire Engineering Design has been undertaken in isolation from other aspects of the Building’s Fire Engineering Design.

On Page 3 of the Case Study Report …

4.2 Objectives & Functional Requirements for Fire Safety of Structures

The fire safety objectives of the airport terminal emphasize the safety of life, conservation of property, continuity of operations and protection of the environment. “

Should these not be the Project-Specific Fire Engineering Design Objectives ?   Since when, for example, is ‘continuity of operations’ a concern in building codes ??

On Page 7 of the Case Study Report …

5.3  Identify Objectives, Functional Requirements & Performance Criteria for Fire Safety of Structure

The Fire Safety Objective of the Steel Structure:  There should be no serious damage to the structure or successive collapse in case of fire.

The Functional Requirements are defined as the followings:

(1)  Prevent or limit the structural failure in case of fire so as to prevent the fire from spreading within the compartment or to the adjacent fire compartment or the adjacent buildings (to prevent fire spread) ;

(2)  Prevent or limit the partial structural failure in case of fire so as to protect the life safety of the occupants and firefighters (to protect life safety) ;

(3)  Prevent or limit the structural deformation or collapse so as not to increase the cost or difficulties of the after-fire restoration (to reduce reconstruction cost).

One of the following Performance Requirements shall be met:

(1)  The load-bearing capacity of the structure (Rd) shall not be less than the combined effect (Sm) within the required time, that is Rd ≥ Sm.  (The maximum permitted deflection for the steel beam shall not be larger than L/400, and the maximum stress of the structure under fire conditions shall not be larger than fyT) ;   or

(2)  The fire resistance rating of the steel structure (td) shall not be less than the required fire resistance rating (tm), that is, td ≥ tm ;   or

(3)  Td – the critical internal temperature of the steel structure at its ultimate state shall not be less than Tm (the maximum temperature of the structure within required fire resistance time duration), that is Td ≥ Tm.  (300 ℃) “

Once again … we see an emphasis on critical temperature, beam deflection (only), and material strength.  L/400 is an impressive Fire Serviceability Limit State … a different world from L/20 or L/30 … but what about other important types of steel structural member deformation, e.g. thermal expansion and distortion ??

Furthermore … if there is a major fire in the area under the lower roof (see Section above) … because of structural continuity, any serious impact on the small frame will also have an impact on the large frame.  For Structural Fire Engineering reasons … would it not be wiser to break the structural continuity … and have the small and large portal frames act independently ?

It is proposed that the Portal Frames will NOT be fully fire protected … just the columns, up to a height of 8 metres only.  If ‘conservation of property’ and ‘continuity of operations’ are important fire engineering design objectives in this project … why isn’t all of the steel being fully protected ???   What would be the additional cost, as a percentage of the total project cost ?

What exactly is infallible about current Design Fires and Design Fire Scenarios ???   Not much.  And in the case of this particular building, should a ‘maximum credible fire scenario’ be at least considered ?

And … what is the fire protection material, product or system being used to protect the Portal Frames ?   Will it be applied, fixed or installed correctly ?   What is its durability ?   Will it be able to resist mechanical damage during the construction process … and afterwards, during the fire event ?   What is the reliability of this form of fire protection measure ??

So many questions …

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Disability Access Certificates (DAC’s) – Parts M & B ? (II)

2009-10-18:  In everyday practice, the usual short introductory text in Technical Guidance Document M (Ireland) which refers to a linkage between ‘access and use’ of a building with ‘fire safety’ has little impact, because it is not explained … and is typically ignored.

In general … the basic problem is that this issue is hardly dealt with … at all … by Local Fire Authorities right across the country in their handling of Fire Safety Certificates … and where it does become part of the process, it receives inadequate attention.  There are exceptions.

A major drawback with the current vertical approach to our Building Regulations … each of the Parts has its own separate Supporting Technical Guidance Document … is that people are not sufficiently aware of the important horizontal linkages between the different Parts.  For example, all of the other Parts must be linked to Part D.  Quick, run to find out what Part D covers !   Another two examples … Part B must also be linked to Part A and Part M … and Part M must also be linked to Part K and Part B.

So … while grudgingly having to accept that the scope of TGD M should have some limit, under the current flawed system … a precise intervention with just one or two sentences, at critical places in the guidance text, would help to improve the overall consideration of fire safety issues, relevant to Part M, by building designers … and client or construction organizations.

Here are a Few Suggestions for Discussion …

1.  Revise Paragraph #0.6 of Draft TGD M (2009) & Add a Title …

Fire Evacuation for All

” Accessibility encompasses the full range of activity related to buildings: to approach, enter, use, egress from under normal conditions, and evacuate a building independently during a fire emergency, in an equitable and dignified manner.  Provision for access and use must, therefore, be linked to provision for fire evacuation.  For guidance on design for evacuation, reference should be made to Technical Guidance Document B (Fire Safety).”

Note:  No such guidance is contained in TGD B (2006).  It would be a great wonder if any person with a disability could actually evacuate a building which had been designed in accordance with TGD B.  To take a simple example … all of the ‘stairways’ in Table 1.5 of TGD B – Minimum Width of Escape Stairways will not facilitate contraflow or the assisted evacuation of mobility and visually impaired people.  Furthermore, those minimum widths specified in the Table may have a clear width which is 200 mm less.  See Methods of Measurement, Paragraph #1.0.10 (c) (iii) … ” a stairway is the clear width between the walls or balustrades, (strings and handrails intruding not more than 30 mm and 100 mm respectively may be ignored) ” !   What an incoherent mess !!

2.  Insert New Sentence at the End of Paragraph #1.1.1 of Draft TGD M (2009) …

Objective (Approach to Buildings)

” Consideration should be given to the use of the approach and circulation routes around a building as accessible routes to a ‘place of safety’ during a fire emergency.”

3.  Insert New Sentence at the End of Paragraph #1.2.1 of Draft TGD M (2009) …

Objective (Access to Buildings)

” Consideration should be given to the use of all entrances to a building as accessible fire exits during a fire emergency.”

4.  Insert New Paragraph at the End of Paragraph #1.3.4.1 of Draft TGD M (2009) …

Passenger Lifts

” Manual handling of occupied wheelchairs in a fire evacuation staircase, even with adequate training for everyone directly and indirectly involved, is hazardous for the person in the wheelchair and those people – minimum three – giving assistance.  The weight of an average unoccupied powered wheelchair, alone, makes manual handling impractical.  Lifts in new buildings should, therefore, be capable of being used for evacuation in a fire situation.  For guidance on the use of lifts for fire evacuation, reference should be made to Technical Guidance Document B (Fire Safety).”

5.  Insert New Paragraph and New Sentence at the End of Paragraph #1.3.4.2 of Draft TGD M (2009) …

Internal Stairs

” To allow sufficient space to safely carry an occupied wheelchair down or up a fire evacuation staircase, and to accommodate contraflow, i.e. emergency access by firefighters entering a building and moving towards a fire, while people are still evacuating from the building to a ‘place of safety remote from the building, the clear unobstructed width (exclusive of handrails and any other projections, e.g. portable fire extinguishers, notice boards, etc.) of the flight of a single, or multi-channelled, stairs should not be less than 1 500 mm.  The surface width of a flight of stairs should not be less than 1 700 mm.”

Note:  See Footnote (5) to Table 1.5 in TGD B (2006) … ” The minimum widths given in the table may need to be increased in accordance with the guidance in TGD M: Access for People with Disabilities.”   DUH ?

And …

” For the purpose of safe assisted fire evacuation of people, the rise of a step should not have a height greater than 150 mm, and the going of a step should not have a depth less than 300 mm.”

6.  Insert New Sentence at the End of Paragraph #1.5.1 of Draft TGD M (2009) …

Objective (Facilities in Buildings)

” Consideration should be given to the use of relevant facilities within a building, by people with disabilities, for the purposes of fire safety, protection and evacuation.”

7.  Insert New Sentence at the End of Paragraph #1.6.1 of Draft TGD M (2009) …

Objective (Aids to Communication)

” Consideration should be given to the use of relevant aids to communication, by people with disabilities, for the purposes of fire safety, protection and evacuation.”

Note:  More guidance could be provided under each of the individual paragraphs of Section #1.6 of Draft TGD M (2009).  See Draft International Accessibility-for-All Standard ISO 21542.

8.  Insert New Section #2.6 of Draft TGD M (2009) …

Fire Safety in Dwellings for People with Disabilities

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