Real Fire

2015 Dublin Declaration on ‘Fire Safety for All’ Adopted !

2015-04-20:  After a lengthy, constructive and very interesting discussion which resulted in some important text revisions … on Friday afternoon in Dublin, 10 April 2015, at the ‘Fire Safety for All’ Conference (www.fire-safety-for-all.eu) … all participants voted to adopt, support and promote the 2015 Dublin Declaration on ‘Fire Safety for All’ in Buildings !

With regard to International Distribution and Promotion of the Declaration … many readers of this Technical Blog belong to varied professional, social and business networks.  I would earnestly ask you to circulate the Declaration widely within those networks, and to actively seek the support of as many organizations and individuals as possible.  This support should be confirmed by means of a simple e-mail message to: fireox@sustainable-design.ie … and I will then add the names of supporters to the Fire Safety for All WebSite (www.fire-safety-for-all.eu).  Copies of the Declaration, in PDF and WORD Formats, can also be downloaded from the WebSite.

Fire-Safety-4-All_smlThis Benchmark Declaration on Accessibility and Fire Safety for People with Activity Limitations … is an essential reference document for all stakeholders and interested parties.  It draws a long-awaited, broad, distinct and stable line in the shifting sands of a rapidly evolving Sustainable Human Environment (social, built, virtual, economic, and institutional) ….

1.   As of 14 July 2015 … 156 Countries, plus the European Union, have ratified the United Nations Convention on the Rights of Persons with Disabilities (CRPD).  Since the Convention became an international legal instrument in 2008, however, the UN CRPD Preamble’s Paragraph (g): ‘mainstreaming disability in sustainable development strategies’ … and Paragraph (v): ‘the importance of accessibility in enabling people to fully enjoy their rights and fundamental freedoms’ … have tended to receive insufficient public attention and scrutiny.  The Dublin Declaration on ‘Fire Safety for All’ in Buildings and the related CIB W14 Research Working Group 5’s Reflection Document have been drafted with those two paragraphs very much in mind.

2.   Although a situation of serious risk for vulnerable building users … it is not appropriate to deal with Fire Safety for All in Buildings under Article 11: ‘Situations of Risk & Humanitarian Emergencies’ of the U.N. Convention on the Rights of Persons with Disabilities … where situations of grave risk are handled, e.g. Extreme Man-Made Events, Hybrid Disasters, Severe Natural Events, Complex Humanitarian Emergencies … all amid Accelerating Climate Change & Variability.

Take the case of an earthquake, for example … where there will be large-scale serious building damage and many, many building collapses throughout an affected region.  On the other hand, when considering fire safety for all in any building … it is necessary that the building shall remain not just structurally stable, but serviceable.

3.   It is more appropriate, particularly since the publication of International Standard ISO 21542 (2011) with its expanded definition of Building Accessibility, that Fire Safety for All be incorporated into the meaning and implementation of Article 9: ‘Accessibility’ of the CRPD … in exactly the same manner that fire safety is fully integrated into everyday mainstream building use, and mainstream building fire safety codes and standards.

As there are no references, at all, to either ‘fire’ or ‘safety’ in Articles 9 … there is much to be explained and clarified in the 2015 Dublin Declaration on ‘Fire Safety for All’ in Buildings, if ‘real’ implementation is to be both practical and successful.

An improved and updated definition of Building Accessibility is contained in Principle 3 of the Dublin Declaration …

‘Accessibility of a Building encompasses the complete cycle of independent use, in a dignified manner and on an equal basis with others … and includes the approach, entry and use of a building and its facilities, egress during normal conditions and removal from its vicinity … and, most importantly, safe evacuation during a fire incident to a place of safety which is remote from the building and reached by way of an accessible route.’

4.   The Dublin Declaration contains a Preamble, Principles 1-9 which are headlined below, and an Appendix with many Terms and Definitions …

Principle 1 – A Human Right
Principle 2 – Successful Implementation
Principle 3 – Building Accessibility
Principle 4 – Design for Safe Evacuation
Principle 5 – Accessible EICT’s
Principle 6 – Fire Safety Skills
Principle 7 – Reasonable Spatial Provision
Principle 8 – Building Management
Principle 9 – Firefighters

5.   Existing approaches to Fire Safety, Protection & Evacuation in Buildings for People with Activity Limitations … as described and illustrated in the notable examples of British Standard B.S. 9999 (2008), Singapore’s FSR 7 (2011), and Hong Kong’s Fire Safety Code Addendum (2014) … are technically inadequate, tokenistic, discriminatory, create barriers to social participation, and violate human rights.  Therefore, any further use or recourse to such existing approaches must be terminated immediately !

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2015  DUBLIN  DECLARATION  ON  ‘FIRE SAFETY FOR ALL’  IN  BUILDINGS
A Call to Action and Successful Implementation !

(Adopted in Dublin, 2015-04-10)

Meeting In  Dublin, Ireland … on Thursday and Friday, 9 and 10 April, 2015

In Co-Operation With  the International Council for Research & Innovation in Building & Construction (CIB), Rehabilitation International’s International Commission on Technology & Accessibility (RI-ICTA), the Global Alliance for Accessible Technologies & EnvironmentS (GAATES), and the EUropean Concept for Accessibility Network (EuCAN) ;

Recognizing  the integral and interdependent nature of the natural and human environments (social, built, virtual, economic and institutional) on this small planet Earth, our common home … and the need for harmonized principles to inspire and guide the peoples of the World in the enhancement of a human environment which cherishes the dignity, worth and many abilities of every person ;

Whereas  in the United Nations Charter, the U.N. Member States pledged their respect for, and the protection and observance of, fundamental human and social rights … and have determined to promote social development and better standards of living for all ;

Recalling  the Universal Declaration of Human Rights (UDHR), adopted on 10th December 1948 … which established a global framework of human and social rights – basic needs and protections – and fundamental freedoms for every person and communal gathering ;

Recalling Also  the Rio de Janeiro Declaration on Sustainable Social Development, Disability & Ageing, adopted on 11th December 2004 … which stressed the importance of the social aspects in Sustainable Human & Social Development ;

Mindful Especially  of the United Nations Convention on the Rights of Persons with Disabilities (CRPD), adopted on 13th December 2006 … the principal aim of which is to ensure that the human environment is sufficiently accessible to permit a vulnerable and major population group in all communities to safely exercise and enjoy the human and social rights and fundamental freedoms described in the 1948 UDHR ;

Working Towards  the achievement of justice, equality of opportunity, social inclusion, active participation and development for every person with an activity limitation in all communities … and recognizing that accessibility of the human environment is an essential prerequisite for the above, and that fire safety for all is a critical life safety component of that accessibility ;

Aware Always  of the universal reality that there is still a strong social stigma associated with disability and, particularly, mental ill-health … that much of the human environment is not accessible for all, and even where it is robustly mandated in law, the quality of that accessibility is poor … and that fire safety guidelines for people with activity limitations in buildings, if they exist, are inadequate and/or tokenistic, and rarely implemented ;

Welcoming the launch of the CIB Working Commission 14: Fire Safety – Research Working Group 5’s Reflection Document: Buildings & ‘Fire Incident Human Behaviour and Abilities’ which presents a practical examination and general overview of fire safety for all

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Addressed to every Country and the European Union – those many Voluntary Parties to the U.N. Convention on the Rights of Persons with Disabilities – and the Politicians, Authorities Having Jurisdiction, State Agencies, Professional Bodies & Institutions, Non-Governmental Organizations, Charitable & Private Organizations, etc., based within those separate jurisdictions:

We Declare That The Following Principles Must …

Be carefully studied, successfully implemented, and independently monitored … supported by Benchmarking, reliable Data and Statistics, and the informed use of pertinent Accessibility & Fire Safety Related Performance Indicators …

Principle 1 – A Human Right

Full and effective accessibility of the Human Environment (social, built, virtual, economic and institutional) is a fundamental human and social right, i.e. a basic need, for people with activity limitations – it is an essential prerequisite for the safe exercise and enjoyment of those rights, protections and freedoms set down in the 1948 Universal Declaration of Human Rights and subsequent international rights instruments … and crucially, for their health, participation, inclusion and development in all communities.

Principle 2 – Successful Implementation

Successful accessibility implementation … meaning high quality accessibility performance in the built environment … is reliant upon:

  • A robust legal base mandating accessibility for all and fire safety for all ;
  • Determined political will ;
  • Sufficient public financial resources ;
  • A compassionate and understanding bureaucracy at all levels ;
  • Competent … meaning duly educated, trained and experienced in accessibility and fire safety design … spatial planners, architects, structural engineers, fire engineers, quantity surveyors, technical controllers, industrial designers, building managers, and people at all levels in construction organizations ;
  • Independent monitoring of accessibility and fire safety performance ;
  • Innovative, well-designed accessibility and fire safety related products and systems which can be shown to be ‘fit for their intended use’.

Principle 3 – Building Accessibility

Accessibility of a Building encompasses the complete cycle of independent use, in a dignified manner and on an equal basis with others … and includes the approach, entry and use of a building and its facilities, egress during normal conditions and removal from its vicinity … and, most importantly, safe evacuation during a fire incident to a place of safety which is remote from the building and reached by way of an accessible route.

Principle 4 – Design for Safe Evacuation

Accessibility design criteria must be infused into all of the practical, day-to-day work of building designers and, especially, in the development of project-specific fire engineering design objectives … and be applied from the initial stages of building design, through to the construction and reliable life cycle operation of vertical and horizontal fire evacuation routes facilitating contraflow, areas of rescue assistance, fire safety related signage, controls and fittings, fire prevention and protection measures, fire safety management procedures, routes to and locations of places of safety, etc., etc.
• Evacuation way finding in buildings must be intuitive and obvious ;
• 3 Keywords for building designers must be: reality – reliability – redundancy.

Principle 5 – Accessible EICT’s

Electronic, information and communication technologies are ubiquitous in today’s complex built and virtual environments.  During a real fire incident in a building, they serve a function which is critical for the safety of all building users and firefighters, property protection, minimizing environmental damage and harm, and sustainability. For that reason, they must have a control and/or user interface which is accessible for all.

Principle 6 – Fire Safety Skills

People with activity limitations who occupy or use a building frequently must be included in all practice fire evacuations, in order to learn the skill of safe independent evacuation to an accessible place of safety remote from the building.  During a real fire incident, evacuation assistance provided by other building users or rescue by firefighters, and the time spent waiting for that assistance or rescue in the building must be kept to an absolute minimum.

People with activity limitations must be actively encouraged to participate in fire safety preparatory planning and regular practices … and, without exception, must be consulted and included in all activities concerning their own evacuation from a building.

Management systems and fire protection measures in buildings are never 100% reliable.  People with activity limitations must, therefore, be actively encouraged to be self-aware in situations of risk, and facilitated in learning the skill of self-protection.

Principle 7 – Reasonable Spatial Provision

Reasonable spatial provision must be allocated in a building for the needs of real users, who vary in the range of their individual behaviour and abilities … and for the real building user population profile which, avoiding discrimination, must reflect a society as a whole.  Concerning fire safety for all and the necessary size, for example, of an area of rescue assistance which adjoins a fire evacuation staircase on every floor in a building … the following indicators, exclusive of extra provision for assistants, must guide the architect and fire engineer in the collaborative design process:

(a)  Minimum reasonable provision for people with disabilities in a building – 10% of design occupant/user population ;

(b)  Minimum reasonable provision for people with activity limitations in a building … 15% of design occupant/user population.

Principle 8 – Building Management

Building managers must ensure that fire safety for all preparatory planning is effective, and that practices are held regularly … before any real fire incident occurs.  And as part of their normal, day-to-day functioning … managers must be fully aware that, without due attention to accessibility-related services, product maintenance and occupant/user welfare policies, the quality of accessibility in a building will rapidly deteriorate.

Personal Emergency Evacuation Plans (PEEPS) must not be used to limit or restrict access to any part of a building and its facilities.

Principle 9 – Firefighters

Firefighters must be trained to interact with and rescue people with activity limitations from buildings, using procedures and equipment which will not cause injury to either.  Fire services must ensure that they operate such procedures and possess such regularly serviced equipment.

Emergency service organizations must operate reliable systems to notify the fire services of emergency situations, which are accessible for all and useable by the public at all times.

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APPENDIX – Terms & Definitions

Area of Rescue Assistance:  A sufficiently large building space directly adjoining, and visible from, a main vertical evacuation route – robustly and reliably protected from heat, smoke and flame during and after a fire – where people may temporarily wait with confidence for further information, instructions, and evacuation assistance or rescue, without obstructing or interfering with the evacuation travel of other building users.

Contraflow Circulation in a Fire Building:  Emergency access by firefighters or rescue teams into a building and towards a real fire … while building users are still moving away from the fire and evacuating the building.

Evacuation from a Fire Building:  To withdraw, or cause to withdraw, all users from a building which is on fire … in pre-planned and orderly phased movements to an accessible place of safety remote from the building.

Fire Compartmentation:  The division of a building into fire-tight compartments by fire, smoke and heat resisting elements of construction, in order to …
a)  contain an outbreak of fire, including any smoke and heat generated by the fire ;
b)  prevent damage, within the building, to other adjoining compartments and spaces ;
c)  protect a compartment interior from external fire attack, e.g. fire spread across the building’s facade or from an adjacent building ;
d)  minimize adverse, or harmful, environmental impacts outside the building.

Human Health:  A state of complete physical, mental and social wellbeing, and not merely the absence of disease or infirmity.

People with Activity Limitations (E) / Personnes à Performances Réduites (F):  Those people, of all ages, who are unable to perform, independently and without aid, basic human activities or tasks – because of a health condition or physical / mental / cognitive / psychological impairment of a permanent or temporary nature.

The above Term includes …

  • wheelchair users ;
  • people who experience difficulty in walking, with or without a facilitation aid, e.g. stick, crutch, calliper or walking frame ;
  • frail, older people ;
  • the very young (people under the age of 5 years) ;
  • people who suffer from arthritis, asthma, or a heart condition ;
  • the visually and/or hearing impaired ;
  • people who have a cognitive impairment disorder, including dementia, amnesia, brain injury, or delirium ;
  • women in the later stages of pregnancy ;
  • people impaired following the use of alcohol, other ‘social’ drugs e.g. cocaine and heroin, and some medicines ;
  • people who suffer any partial or complete loss of language related abilities, i.e. aphasia ;
  • people impaired following exposure to environmental pollution and/or other irresponsible human activities, e.g. war and terrorism ;

and …

  • people who experience a panic attack in a real fire situation or other emergency ;
  • people, including firefighters, who suffer incapacitation as a result of exposure, during a real fire, to smoke and poisonous or toxic substances, and/or elevated temperatures.

Place of Safety:
•  Any accessible location beyond a perimeter which is [100] metres from the fire building or a distance of [10] times the height of such building, whichever is the greater ;   and
•  Where necessary triage can safely be rendered … and from where effective medical care and supervision can be organized and provided within one hour of injury (the ‘golden hour’) ;   and
•  Where people can be identified.

Note: If there is a risk of an explosion associated with a fire – multiply the numbers in square brackets above by 4.

Progressive Damage in Fire / 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.

Note: Fire-induced progressive damage may commence long before there is any breach in the integrity of a fire compartment’s boundaries.

Real Fire:  A fire which develops in a building and is influenced by such factors as the type of building and its occupancy (numbers, abilities and activities) ;  the combustible content (fire load) ;  the ventilation, geometry and thermal properties of the fire compartment or building space (should no fire compartmentation exist) ;  the fire suppression systems in the building, and the actions of firefighters.

Skill:  The ability of a person – resulting from proper training and regular practice – to carry out complex, well-organized patterns of behaviour efficiently and adaptively, in order to achieve some end or goal.

Social Environment:  The complex network of real and virtual human interaction – at a communal or larger group level – which operates for reasons of tradition, culture, business, pleasure, information exchange, institutional organization, legal procedure, governance, human betterment, social progress and spiritual enlightenment, etc.

Social Rights:  Rights to which an individual person is legally entitled, e.g. the right to free elementary education (Art.26(1), UDHR), but which are only exercised in a social context with other people, and with the active support of a competent legal authority, e.g. a Nation State.

Social Wellbeing:  A general condition – in a community, society or culture – of health, happiness, creativity, responsible fulfilment, and sustainable development.

Virtual Environment:  A designed environment, electronically generated from within the built environment, which may have the appearance, form, functionality and impact – to the person perceiving and actually experiencing it – of a real, imagined and/or utopian world.

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NIST WTC Recommendations 4-7 > Structural Fire Endurance

First Post in This Series …

2011-10-25:  NIST’s Recommendations on the 9-11 WTC Building Collapses … GROUP 1. Increased Structural Integrity – Recommendations 1, 2 & 3 (out of 30)

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2011-11-18:  SOME PRELIMINARY COMMENTS …

  1.     Before launching into the next Group of NIST WTC Recommendations, it would be useful to distinguish between the following technical terms … which have been adapted from ISO/TR 10158: ‘Principles and Rationale Underlying Calculation Methods in Relation to Fire Resistance of Structural Elements’

Real Fire:  A fire which develops in a building and which is influenced by such factors as the type of building and its occupancy;  the combustible content (fire load);  the ventilation, geometry and thermal properties of the fire compartment, or building space (should no fire compartmentation exist);  the fire suppression systems in the building and the actions of the fire services.

Real Fires are complex phenomena.  Consequently, in structural fire engineering, idealized versions of ‘real fires’ are employed.

Experimental Fire:  A full or reduced scale fire with specified and controlled characteristics.

Design Fire:  A fire with specified exposure data intended for use in connection with structural fire engineering calculations.

A Design Fire may either be representative of the thermal exposure described by the standard time-temperature-pressure relationship in an International/European/National Standard, or some non-standard exposure intended to simulate particular fire exposure conditions.

However, in SDI Technical Guidance Note 95/102: ‘Proper Evidence of a Fire Test Result within the European Economic Area (EEA)’, issued on 22 May 1995, I included the following caution …

#1.7  A Fire Test in a Fire Test Laboratory, involving exposure of a test specimen or prototype to ‘test fire’ conditions, gives only a limited indication of:  (a) the likely performance of a particular product, material or component when exposed to ‘real fire’ conditions;  and (b) the suitability of a product, material or component for a particular end use.

  2.     In conventional fire engineering, much confusion arises because of a failure to properly distinguish between these two concepts …

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.

Structural Reliability

The ability of a structural system to fulfil its design purpose, for a specified time, under the actual environmental conditions encountered in a building.

[ In structural fire engineering, the concern must be that the structure will fulfil its purpose, both during the fire – and for a minimum period afterwards, during the ‘cooling phase’.]

  3.     Therefore, with regard to Recommendation 6 … it is more correct and precise to refer to ‘Steel Fire Protection Systems’, rather than to ‘steel fire resisting materials’ !   AND … the same questions must be asked about All Lightweight Steel Fire Protection Systems … not just the sprayed systems.

Lightweight Fire Protection Systems are also used to protect concrete in buildings and tunnels.

  4.     These 2005 NIST Recommendations will later be confirmed, and further reinforced, by the 2008 NIST Recommendations.  Bringing Recommendation 7, below, closer to home … it is interesting to note that a very necessary discussion on the technical adequacy of the approach taken to structural performance in fire … in both Technical Guidance Document B (Ireland) and Approved Document B (England & Wales) … has yet not even commenced !

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2005 NIST WTC RECOMMENDATIONS

GROUP 2.  Enhanced Fire Endurance of Structures

The procedures and practices used to ensure the fire endurance of structures should be enhanced by improving the technical basis for construction classifications and fire resistance ratings, improving the technical basis for standard fire resistance testing methods, use of the ‘structural frame’ approach to fire resistance ratings, and developing in-service performance requirements and conformance criteria for sprayed fire resisting materials.

NIST WTC Recommendation 4.

NIST recommends evaluating, and where needed improving, the technical basis for determining appropriate construction classifications and fire rating requirements (especially for tall buildings) – and making related code changes now, as much as possible – by explicitly considering factors including: *

[ * F-23  The construction classification and fire rating requirements should be risk-consistent with respect to the design-basis hazards and the consequences of those hazards.  The fire rating requirements, which were originally developed based on experience with buildings less than 20 storeys in height, have generally decreased over the past 80 years since historical fire data for buildings suggest considerable conservatism in those requirements.  For tall buildings, the likely consequences of a given threat to an occupant on the upper floors are more severe than the consequences to an occupant on the first floor or the lower floors.  For example, with non-functioning elevators, both of the time requirements are much greater for full building evacuation from upper floors and emergency responder access to those floors.  It is not clear how the current height and areas tables in building codes consider the technical basis for the progressively increasing risk to an occupant on the upper floors of tall buildings that are much greater than 20 storeys in height.]

  • timely access by emergency responders and full evacuation of occupants, or the time required for burnout without partial collapse ;
  • the extent to which redundancy in active fire protection systems (sprinklers and standpipe, fire alarm, and smoke management) should be credited for occupant life safety ; *

[ * F-24  Occupant life safety, prevention of fire spread, and structural integrity are considered separate safety objectives.]

  • the need for redundancy in fire protection systems that are critical to structural integrity ; *

[ * F-25  The passive fire protection system (including fire protection insulation, compartmentation, and fire stopping) and the active sprinkler system each provide redundancy for maintaining structural integrity in a building fire, should one of the systems fail to perform its intended function.]

  • the ability of the structure and local floor systems to withstand a maximum credible fire scenario* without collapse, recognizing that sprinklers could be compromised, not operational, or non-existent ;

[ * F-26  A maximum credible fire scenario includes conditions that are severe, but reasonable to anticipate, conditions related to building construction, occupancy, fire loads, ignition sources, compartment geometry, fire control methods, etc., as well as adverse, but reasonable to anticipate operating conditions.]

  • compartmentation requirements (e.g. 1,200 sq.m *) to protect the structure, including fire rated doorsets and automatic enclosures, and limiting air supply (e.g. thermally resisting window assemblies) to retard fire spread in buildings with large, open floor plans ;

[ * F-27  Or a more appropriate limit, which represents a reasonable area for active fire fighting operations.]

  • the effect of spaces containing unusually large fuel concentrations for the expected occupancy of the building ;   and
  • the extent to which fire control systems, including suppression by automatic or manual means, should be credited as part of the prevention of fire spread.

Adoption of this Recommendation will allow building codes to distinguish the risks associated with different building heights, fuel concentrations, and fire protection systems.  Research is needed to develop the data and evaluate alternative proposals for construction classifications and fire ratings.  Model Building Codes:  A comprehensive review of current construction classifications and fire rating requirements and the establishment of a uniform set of revised thresholds with a firm technical basis that considers the factors identified above should be undertaken.*

[ * F-28  The National Fire Protection Association (NFPA) 5000 model code and the International Building Code (IBC) both recognize the risks associated with different building heights and accepted changes in 2001 and 2004, respectively.  Both model codes now require that buildings 126 metres and higher have a minimum 4 hour structural fire resistance rating.  The previous requirement was 2 hours.  The change provides increased fire resistance for the structural system leading to enhanced tenability of the structure and gives firefighters additional protection while fighting a fire.  While NIST supports these changes as an interim step, NIST believes that it is essential to complete a comprehensive review that will establish a firm technical basis for construction classifications and fire rating requirements.]

NIST WTC 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.

This effort should address the technical issues listed below: *

[ * F-29  The technical issues were identified from the series of four fire resistance tests of the WTC Floor system, and the review and analysis of relevant documents that were conducted as part of this Investigation.]

a.     Criteria and test methods for determining:

  • structural limit states, including failure, and means for measurement ;
  • effect of scale of test assembly versus prototype application, especially for long-span structures that significantly exceed the size of test furnaces ;
  • effect of restraining thermal expansion (end-restraint conditions) on test results, especially for long-span structures that have greater flexibility ;
  • fire resistance of structural connections, especially the fire protection required for a loaded connection to achieve a specified rating ; *

[ * F-30  There is a lack of test data on the fire resistance ratings of loaded connections.  The fire resistance of structural connections is not rated in current practice.  Also, standards and codes do not provide guidance on fire protection requirements for structural connections when the connected members have different fire resistance ratings.]

  • effect of the combination of loading and exposure (time-temperature profile) required to adequately represent expected conditions ;
  • the repeatability and reproducibility of test results (typically, results from a single test are used to determine the rating for a component or assembly) ;   and
  • realistic ratings for structural assemblies made with materials that have improved elevated temperature properties (strength, modulus, creep behaviour).

b.     Improved procedures and guidance to analyze and evaluate existing data from fire resistance tests of building components and assemblies for use in qualifying an untested building element.

c.     Relationships between prescriptive ratings and performance of the assembly in real fires.

Affected National and International Standards: * ASTM E 119, NFPA 251, UL 263, and ISO 834.  Model Building Codes:  The standards should be adopted in model building codes by mandatory reference to, or incorporation of, the latest edition of the standard.

[ * F-31  While the NIST Recommendations are focused mainly on U.S. national standards, each U.S. standard has counterpart international standards.  In a recent report (ISO/TMB AGS N 46), the International Organization for Standardization (ISO), through its Advisory Group for Security (AGS), has recommended that since many of the ISO standards for the design of buildings date back to the 1980’s, they should be reviewed and updated to make use of the studies done by NIST on the World Trade Center disaster, the applicability of new technology for rescue from high buildings, natural disasters, etc.  ISO’s Technical Advisory Group 8 co-ordinates standards work for buildings.]

NIST WTC Recommendation 6.

NIST recommends the development of criteria, test methods, and standards:  (1) for the in-service performance of Sprayed Fire Resisting Materials (SFRM, also commonly referred to as fire protection insulation) used to protect structural components;  and (2) to ensure that these materials, as installed, conform to conditions in tests used to establish the fire resistance rating of components, assemblies, and systems.

This should include:

  • Improved criteria and testing methodologies for the performance and durability of SFRM (e.g. adhesion, cohesion, abrasion, and impact resistance) under in-service exposure conditions (e.g. temperature, humidity, vibration, impact, with/without primer paint on steel*) for use in acceptance and quality control.  The current test method to measure the bond strength, for example, does not distinguish the cohesive strength from the tensile and shear adhesive strengths.  Nor does it consider the effect of primer paint on the steel surface.  Test requirements that explicitly consider the effects of abrasion, vibration, shock, and impact under normal service conditions are limited or do not exist.  Also, the effects of elevated temperatures on thermal properties and bond strength are not considered in evaluating the performance and durability of SFRM.

[ * F-32  NIST tests show that the adhesive strength of SFRM on steel coated with primer paint was a third to half of the adhesive strength on steel that had not been coated with primer paint.  The SFRM products used in the WTC towers were applied to steel components coated with primer paint.]

  • Inspection procedures, including measurement techniques and practical conformance criteria, for SFRM in both the building codes and fire codes for use after installation, renovation, or modification of all mechanical and electrical systems and by fire inspectors over the life of the building.  Existing standards of practice (AIA MasterSpec and AWCI Standard 12), often required by codes for some buildings need to be broadly applied to both new and existing buildings.  These standards may require improvements to address the issues identified in this Recommendation.
  • Criteria for determining the effective uniform SFRM thickness – thermally equivalent to the variable thickness of the product as it is actually applied – that can be used to ensure that the product in the field conforms to the near uniform thickness conditions in the tests used to establish the fire resistance rating of the component, assembly, or system.  Such criteria are needed to ensure that the SFRM, as installed, will provide the intended performance.
  • Methods for predicting the effectiveness of SFRM insulation as a function of its properties, the application characteristics, and the duration and intensity of the fire.
  • Methods for predicting service life performance of SFRM under in-service conditions.

Affected Standards:  AIA MasterSpec and AWCI Standard 12 for field inspection and conformance criteria; ASTM standards for SFRM performance criteria and test methods.  Model Building Codes:  The standards should be adopted in model building codes by mandatory reference to, or incorporation of, the latest edition of the standard.  (See Recommendation 10 for more on this issue.)

NIST WTC Recommendation 7.

NIST recommends the adoption and use of the ‘structural frame’ approach to fire resistance ratings.  This approach requires that structural members – such as girders, beams, trusses, and spandrels having direct connection to the columns, and bracing members designed to carry gravity loads – be fire protected to the same fire resistance rating as columns.  This approach is currently required by the International Building Code (IBC), one of the model codes, and is in the process of adoption by NFPA 5000, the other model code.  This requirement ensures consistency in the fire protection provided to all of the structural elements that contribute to overall structural stability.*  State and local jurisdictions should adopt and enforce this requirement.

[ * F-33  Had this requirement been adopted by the 1968 New York City building code, the WTC floor system, including its connections, would have had the 3 hour rating required for the columns since the floors braced the columns.]

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