The seismic events that have damaged cities and towns in central Italy in recent years destroyed, or irreparably damaged, important examples of architecture. Behind several of these damages, it is known among experts in the sector that bad management of the safety interventions of the buildings must be recognized. Emblematic cases can be identified in the earthquakes that, between 1997 and 2017, struck the regions of Abruzzo and Umbria in Italy.Continue reading “How Cultural Divide can put Cultural Heritage at Risk”
Many historic buildings are made with stone structures. In addition to the various benefits that this type of material, which is diversified by composition, aggregation and geometry according to historical periods and geographical areas, it must be remembered that exposure to fire constitutes in most cases an important vulnerability. Even recently, several cases of fire have highlighted the importance of designing from fire, in buildings belonging to the cultural heritage, building elements to which adequate attention is not always paid.
The case of the fire that seriously damaged the chapel that housed the Holy Shroud in Turin, on April 11, 1997, can be considered iconic in this regard. For its restoration it was necessary to open the quarry near the place from which at the time the stone material with which the supporting structures had been made had been extracted (see reference, page 25) . Among other things, the individual blocks had been designed and installed with techniques of which the memory had been lost and which forced the restorers to a specific study.Continue reading “Fire Threat to Stones of Historic and Cultural Heritage Buildings”
Historic buildings are by their nature subject to the degradation that time and atmospheric agents entail. To limit the damage that degradation causes to heritage artefacts, the first requirement is the periodic or, better, continuous control of their state of conservation. The technologies available for this purpose are constantly evolving.Continue reading “Monitoring and Maintenance of Archaeological Sites: the Conference Proceedings”
It is worldwide known that the restoration of Notre Dame, severely damaged by a massive fire on 15 April 2019 will be supported by the wealth of data acquired few years before, in order to release the Ubisoft’s ‘Assassin’s Creed: Unity. This fortuitous case highlights an aspect that could become critical in the conservation of works of art, starting with buildings and monuments. The meticulous scanning, with a precision of not less than 5 mm, has made evident to the public an aspect already known to the experts: the reconstruction or restoration of assets damaged by time, war events and malicious or negligent actions they can be potentially helped if the goods themselves have been documented with laser scanning or photogrammetry techniques. The same consideration can be applied to the emergency assessments on the damage and on the level of risk of collapse that, for example after an earthquake, the first responders must perform to allow the rescue of people, the recovery of assets and the safety of non-collapsed structures.Continue reading “Results of H2020 STORM Project in the Assessment of Damage to Cultural Heritage Buildings Following Seismic Events”
Climate change, presumably, will affect the way buildings will be designed and managed. Also museums are challenged by such risk and a new kind of approach needs to be studied.
Among the wealth of websites and papers that the internet web allows to read about the climate change issue, Managing Indoor Climate Risks in Museums has the gift of explaining the big picture and, at the same time, giving practical tips to the many professionals that need to be supported in studying and applying real-world solution to a new problem.Continue reading “How Climate Change will affect Museums: a book about Indoor Risks”
CURE (Culture in City Reconstruction and Recovery) is a position paper published in 2018 by UNESCO and the World Bank Group that offers, according the foreword (Mr Enrico Ottone and Mr Ede Ijjasz-Vasquez), “a framework on Culture in City Reconstruction and Recovery and operational guidance for policymakers and practitioners for the planning, financing, and implementation phases of post-crisis interventions for city reconstruction and recovery“. Continue reading “CURE: an UNESCO – World Bank Group Position Paper on Cultural Heritage and Reconstruction”
On October 2018 ICCROM (the intergovernamental organization on International Centre for the Study of the Preservation and Restoration of Cultural Property) has published a couple of documents about “First Aid to Cultural Heritage in times of crisis”: a 176 pages pdf handbook and a 104 pages pdf toolkit. Continue reading “First Aid to Cultural Heritage in Times of Crisis – a double ICCROM publication”
Protecting Cultural Heritage is mainly aimed at avoiding that any kind of hazard could pose an excessive risk to the objects that must be preserved. There are conditions, nonetheless, that oblige to evacuate the artefacts, since the preventive measures cannot be anymore effective. So, in specific situations, museums and their staff may go through challenging times due both to natural disasters and climate change.
In the case of museums, when they are threatened for their role in protecting and valorizing precious witnesses of the past and human creativity, their intrinsic value for intercultural dialogue and mutual understanding must be protected and supported.
A problem neglected by the most of the studies concerning the protection of Cultural Resources against natural hazards deals with the exposition of archaelogical artefacts to vegetation fire risks. All tangible and intangible cultural assets can be damaged by fires. Thus, archaeological remains are exposed to the risk caused by forest fires.
Risks to cultural heritage vary from catastrophic events (such as earthquakes, floods, etc) to gradual processes (such as chemical, physical, or biological degradation). The result is loss of value to the heritage. Sometimes, the risk does not involve any type of material damage to the heritage asset, but rather the loss of information about it, or the inability to access heritage items. So, heritage managers need to understand these risks well so as to make good decisions about protection of the heritage (for future generations) while also providing access for the current generation. ICCROM (Intergovernamental Organisation devoted to protect Cultural Heritage) and the Canadian Conservation Institute have published the “The ABC Method: a risk management approach to the preservation of cultural heritage”.
The standard describes principles and practices of protection for cultural resource properties (museums, libraries, and places of worship etc.), their contents, and collections, against conditions or physical situations with the potential to cause damage or loss. The updates for the 2017 edition include:
- expanded provisions for outdoor collections and archaeological sites and their protection against wildfire;
- further clarification of sprinkler system corrosion protection criteria;
- mandated integrated system testing per NFPA 4, Standard for Integrated Fire Protection and Life Safety System Testing;
- the addition of numerous events to Annex B, Fire Experience in Cultural Properties.
According to the 909 code, libraries, museums, and places of worship housed in historic structures have also to comply with the requirements of NFPA 914 (Code for Fire Protection of Historic Structures).
The standard includes provisions for fire prevention, emergency operations, fire safety management, security, emergency preparedness and inspection, testing, and maintenance of protection systems.
As in the previous editions, criteria are provided for new construction, addition, alteration, renovation, and modification projects, along with specific rules addressing places of worship and museums, libraries, and their collections.
Historic District Protection Planning A Case Study – Lexington, Virginia
The City of Lexington, located in the Shenandoah Valley of Virginia, was established as the town of Lexington in 1778. Today, Lexington has a permanent population of about 7500 with another 4000-5000 students attending Washington and Lee University and the Virginia Military Institute from September through May. Lexington is well known for its architecture and historic preservation. Tourism and higher education are its major industries and its downtown is a thriving collection shops and restaurants, many housed in restored buildings dating from the late 18th to the early 20th century. Lexington is a typical small city in southern America: many buildings in the downtown area have party walls, construction tends to be brick exteriors over wood framing with combustible roofs, and some older buildings are completely wood frame construction. The streets in Lexington, while not as narrow as many streets in Europe, are narrow when compared to the size of most modern fire apparatus.
The Lexington Presbyterian Church Fire
Lexington Presbyterian, a Greek revival style church, was completed in 1845 and it is one of the centerpieces of Lexington’s history and its visual appeal. Lexington was home to Confederate General Thomas J. “Stonewall” Jackson, and he worshipped at the church in the years leading up to the American Civil War. The sanctuary underwent some renovation between 1845 and 2000, but overall the building changed very little and there was no fire detection or fire suppression system installed when in the summer of 2000 the governing board hired a contractor to repaint the exterior of the building. The board, aware that the dry, 155 year old long-leaf yellow pine wood in the building posed a greater fire hazard than newer material, had the contractor chosen for the work demonstrate the hot-iron technique he proposed to use to soften the paint before scrapping it off. The board approved the process and the contractor began work. On Tuesday, July 18, as workmen were using a hot iron to strip paint off of a cornice around the base of the church’s clock tower, the hot iron apparently ignited a fire in the roof area of the wood frame structure that destroyed one sanctuary and caused the clock tower to collapse.
According to fire investigators from the Virginia State Fire Marshall’s Office, workmen removing paint from a cornice at the base of the clock tower noticed smoke at about 9:30 a.m. The workmen searched for the source of the smoke and found a fire inside the clock tower behind the cornice they had been working on. The workmen attempted to extinguish the fire, and when they could not, they notified the Lexington Volunteer Fire Department. Some volunteer firefighters responded quickly, but since it was a normal workday and most of the members were at work, many were delayed getting to the church and calls for mutual aid went out to other nearby jurisdictions. By 10:00 a.m., heavy smoke was pouring out around the base of the clock tower.
Fire fighters began to battle the blaze with ladder pipes shortly after 10:00 a.m., but by that time the fire in the clock tower was fully developed. Firefighters worked to save the clock tower through the morning; however, the combination of the highly combustible wood frame construction of the church and the amount of water needed to fight the blaze put a strain on the city’s aging water system.
At about noon the clock tower finally collapsed. Fire investigators pointed out that the firefighters did an excellent job keeping the fire from spreading to other structures and because of their efforts no one was injured when the clock tower collapsed into the street.
￼￼Damage to the building was estimate at $2.5 million, and shortly after the fire the church board announced the church would be restored to its original condition and restoration work began soon afterward. The restoration was substantially completed when a new clock tower was installed on March 5, 2002.
A senior architectural historian with the Virginia Department of Historic Resources pointed out after the fire that using heat to strip paint on old wood fixtures that are hollow or that cannot be seen from behind, like the cornices that were being stripped at Lexington Presbyterian where rats or birds sometimes build nests, can cause combustible materials to catch fire without workers knowing it.
In August 2000 the president of the Rockbridge County Historic Society called and asked me to come to Lexington to share information about how Colonial Williamsburg protects its historic buildings and to see if some of those things might be adapted to help Lexington improve protection in its historic district. She also wanted to know how the concepts in the 1997 edition of NFPA 909, Standard for Protection of Cultural Resources might be applied to historic districts. As a first step she arranged a one-day workshop for members of Lexington’s city government, merchants, and other interested parties. The workshop was surprisingly well attended and during the discussions it became evident to the political leaders that much of what made Lexington an attraction for tourism could be lost in a single fire. After the workshop I met with the mayor, the chief of the volunteer fire department, and the president of the Rockbridge County Historic Society to brainstorm ideas to improve fire safety in Lexington’s historic district. In the discussion we identified four major challenges:
- Many of the buildings in the historic district have party walls, and some interconnect at the attic level. The fire department was aware of some of the interconnections; however, the fire chief suspected many more existed that were not on any drawings or building plans.
- The Commonwealth of Virginia has a statewide fire prevention code, but in a city as small as Lexington that has a volunteer fire department no one locally enforces the code and any inspections have to be done by the State Fire Marshall’s office. As with most state agencies, the Virginia State Fire Marshall’s office has a small staff to cover a very large area. In practice, the only inspections the State Fire Marshall’s office can do are in the largest state-owned facilities; so, there is very little, if any, enforcement of fire prevention regulations in privately owned buildings in cities like Lexington.
- Lexington’s aging water supply system was challenged to provide enough water to fight the fire in the church and the fire chief expressed concern about its ability to handle a fire spreading from building to building in the downtown area through interconnecting attics.
- Access is difficult for fire apparatus in many parts of the downtown area because of traffic congestion and narrow streets, particularly during the summer when tourism is at its height.
Two initiatives were undertaken as a result of the discussion:
- The Rockbridge County Historic Society and the Lexington Volunteer Fire Department agreed to focus efforts on a public education program in fire safety management. To help with the project, local residents with backgrounds in fire protection and fire suppression were recruited to conduct public awareness campaigns, fire safety educational programs, and voluntary fire safety inspections for merchants and home owners. Lexington is a popular retirement area for professionals from urban areas in the northeast United States, and several highly qualified individuals volunteered to assist with the project.
- The Lexington City Council agreed to create a position in the Building Department for an inspector who would devote 50% of his time to building code issues and the other 50% to conducting inspections to enforce the Virginia Statewide Fire Prevention Code
More than a decade has passed and over those years I’ve drawn the following lessons from my experience in Lexington.
1. The fire codes and standards in place at the time, and since, including the most recent editions of NFPA 909, Code for the Protection of Cultural Resource Properties – Museums, Libraries and Places of Worship and NFPA 914, Code for Fire Protection of Historic Structures provide no guidance on planning and implementing fire protection programs for historic districts. The NFPA Cultural Resources Committee has been discussing the issues for several years, and it hopes to provide some guidance on the subject in the 2015 edition of NFPA 914. In 2000, the NFPA Cultural Resources Committee was several years away from the paradigm shift it made in the 2010 and 2013 editions of NFPA 909 and the upcoming 2015 edition of NFPA 914 that take an all-hazards approach to protection planning. The shift was crucial because it focused protection planning efforts on the outcome of a comprehensive vulnerability analysis. Such an approach is especially important when thinking of protection in historic districts where one way to approach the issue is to think of the historic district as a very large multiple use occupancy building with multiple owners /tenants (like an apartment building or condominium). From that perspective the district is analogous to a museum building that contains a collection – that is the individual buildings inside the district – and provides the support infrastructure, utilities, and services to maintain them. The planning issues are similar, as well. For example, egress is a primary concern in both, particularly during an earthquake, flood, or conflagration; however, ingress is also a significant issue for both because the collection (buildings, artifacts, or works of art) must be protected in place and to do that, emergency responders must have ready access. Other common issues include water supply (or lack thereof), occupant notification, fire department response time, fire prevention, security and planning for emergency operations and damage limitation.
2. The assessment we did in Lexington was flawed because it addressed only a few of the vulnerabilities, so the resulting action plans only scratched the surface of the problem. The steps taken in Lexington after the fire in 2000 only addressed two limited aspects of the problem (education and enforcement) but failed to address the significant infrastructure issues (water supply, limited availability of volunteer firefighters during the normal work day, fire department access during the busy summer months in the downtown area, installation of automatic sprinklers, etc.). A comprehensive vulnerability assessment of all the hazards is the key to a successful protection plan in a building or in an historic district.
3. Dividing an inspector between building department duties and fire prevention code enforcement probably is not a sustainable model. Building departments are partially self-sustaining because they generate revenues from building permits and plan reviews while fire prevention activities generate no direct revenue. As a result, when municipalities face budget shortfalls, as they have since 2008, they tend to focus on activities that generate income and that moves fire prevention code enforcement to the back burner. After all, governmental memories are short and fires are low probability events even if the consequences can be devastating.
Deborah Freeland (Area Senior Vice President Property Loss Control Arthur J Gallagher & Co.)and Donald Moeller (Principal The Fire Consultants, Inc.) explain the activity of the NFPA Committees 909 e 914 to improve fire protection of cultural and historical heritage.
Download the pdf (without slides with pictures) presented during the september 20, 2012, Venice meeting about emergencies in historical centers: 1
Steve Emery, Fire Safety Adviser for English Heritage, has presented in Venice, during the September 20th international meeting, how English Heritage is training firefighters to rescue operations when historical buildings are interested.
The key points of the presentation are:
1. Standardise Emergency Plans
2. Standardise Training
3. Trainwith Fire Services
4. Maintain the Plans
5. Desktop Exercises
6. Cross Organisation Help and Liaison
The presentation: Emery
VENICE – SCUOLA GRANDE DI SAN GIOVANNI EVANGELISTA
20 September 2012: International Workshop – Protecting historic centres during emergencies
The Italian National Fire Corps (CNVVF) has organized the meeting, which will address to historical centers emergencySeptem,nbre . The use of IT technologies in this field and the techniques used to put in place provisional works to save historical buildings after an earthquake will be shown, with reference to the l’Aquila earthquake experience.
Some presentation will show problems of fire protection in historical buildings.
Session 1 – Technical codes and case studies –
Chairman Maurizio Crovato (Chief editor of RAI International)
- 10.00 Nfpa 909 and 914 and statistics – Donald Moeller – Deborah Freeland (NFPA)
- 10.20 Fire standards in Italy: problems and solutions – Luca Nassi (CNVVF)
- 10.40 Toronto Distillery district – Fred Leber (Leber/Rubes Inc.)
- 11.00 Protection of the Historical Architecture and criteria of Equivalent Safety – Renata Codello (Soprintendency of Venice)
- 11.50 Thun Castle – Francesco Notaro, Emanuele Gissi (CNVVF)
- 12.10 Lexington Historic district – Danny Mac Daniel (Colonial Williamsburg Foundation)
- 12.30 FSE applied to historical building in Venice – Andrea Ferrari – Luciano Nigro (AIIA – SFPE Italian Chapter)
- 12.50 Alaska Historic Area – Steve Peterson (US Department of the Interior)
13.10 Questions and discussion
Session 2 – Emergency management – Chairman Loris Munaro (CNVVF)
- 14.30 ICT and emergencies in historic districts – Stefano Marsella (CNVVF)
- 14.50 Mass Notification – Tom Norton (Norel Service Company) – Wayne Moore (Hughes Associates, Inc)
- 15.10 Heritage buildings and the L’Aquila and Emilia earthquakes: lessons learnt – Marco Cavriani (CNVVF) – Stefano Grimaz (Udine University)
- 15.30 Training the staff to fire and other emergencies: the National Trust experience – Steve Emery (English Heritage)
DOWNLOAD THE LEAFLET: Venice Provisional Program – vers. 29.8.2012
Photogrammetry and Remote Sensing is the art, science, and technology of obtaining reliable information from noncontact imaging and other sensor systems about the Earth and its environment, and other physical objects and processes through recording, measuring, analyzing and representation.
The International Society for Photogrammetry and Remote Sensing, devoted to the development of international cooperation for the advancement of photogrammetry and remote sensing and their applications.
The society has published on its website among other conference proceedings the paper concerning “fire detection, and 3D fire propagation estimation for the protection of cultural heritage areas“.
In the abstract of the paper the Authors (Kosmas Dimitropoulos, Kovanc Köse, Nikos Grammalidis, and Enis Cetin) statesthat beyond taking precautionary measures to avoid a forest fire, early warning and immediate response to a fire breakout are the only ways to avoid great losses and environmental and cultural heritage damages. To this end, this paper aims to present a computer vision based algorithm for wildfire detection and a 3D fire propagation estimation system. The main detection algorithm is composed of four sub-algorithms detecting:
- (i) slow moving objects,
- (ii) smoke-coloured regions,
- (iii) rising regions,
- (iv) shadow regions.
After detecting a wildfire, the main focus should be the estimation of its propagation direction and speed. If the model of the vegetation and other important parameters like wind speed, slope, aspect of the ground surface, etc. are known; the propagation of fire can be estimated. This propagation can then be visualized in any 3D-GIS environment that supports KML files.
In the conclusions, the Authors state that “Early warning and immediate response to a fire breakout are the only ways to avoid great losses and environmental and cultural heritage damages. Hence, the most important goals in fire surveillance are quick and reliable detection and localization of the fire. It is much easier to suppress a fire when the starting location is known, and while it is in its early stages. Information about the progress of fire is also highly valuable for managing the fire during all its stages. Based on this information, the fire fighting staff can be guided on target to block the fire before it reaches cultural heritage sites and to suppress it quickly by utilizing the required fire fighting equipment and vehicles.“
This database was set up by the public body English Heritage to enable all those responsible in any capacity for historic buildings to share information on related fire safety matters.
The database has now been expanded to allow PDFs of research reports to be attached, as well as giving contact points for current or planned projects and details of published reports.
this is the link to FReD Web page:
Improving fire safety level of historical buildings is one of the most common problems to deal with after a fire risk assessment. The theme is not easy, since fire safety technical issues are relevant as conservation ones. In August 1989, the US Government Agency General Service Administration published the paper “Fire Safety Retrofitting in Historical Buildings” in cooperation with the Advisory Council on Historic Preservation.
The document provides guidance to ensure that fire safety retrofitting has minimal impact on the historic features of the property.
State of New South Wales (Australia) has published the Guidelines on fire safety in heritage buildings. In the introduction to the guidelines it is stated that fires in buildings are life threatening and often occur without warning. This gives building occupants little time to react – to fight the fire or evacuate the building. Prevention of fires is the most effective method of dealing with this threat and is the responsibility of both building owners and statutory authorities.
Current building regulations are encompassed in the Building Code of Australia (BCA). Most of NSW heritage buildings were built prior to the adoption of these regulations. In fact some of our very old buildings predate the existence of any formal building regulations in Australia. Many heritage buildings do not meet the full requirements of current building regulations and may need upgrading for fire safety.
The Guidelines, published also in the official Cost C17 Action website, can be downloaded also from this post:
We publish the paper concerning the arson threat to the built heritage already published by the COST Action C17: Built Heritage: Fire Loss to Historic Buildings in its Final Report Part 1 (pages 90-92)
La Fenice Venice
On Friday 30 March 2001, a court in Venice found two electricians guilty of setting fire to La Fenice opera house in the city in 1996. Enrico Carella and his cousin, Massimiliano Marchetti, were found to have set the building ablaze because their company was facing heavy fines over delays in repair work. Mr Carella, the company’s owner, was sent to prison for seven years, while Mr Marchetti received a six-year sentence. The rebuilding of the famous theatre, for which Giuseppi Verdi composed several operas, was delayed and did not re-open until 2004. The fire on 29 January 1996 happened as the Teatro La Fenice was being renovated. The subsequent rebuilding did not go according to plan and the original German-Italian consortium of Holzmann-Romagnoli had asked for supplementary and fee waivers before the work was re-tendered by the City Mayor Paolo Costa.
Sinsheim Mosque, Germany
On the 18 November 2004 unknown individuals threw a Molotov cocktail at a mosque near Heidelberg in Germany. A glass bottle filled with flammable liquid was tossed against the entrance of the Sinsheim mosque. The fire was discovered and extinguished after it caused around €10,000 damage to the wooden door and the glass window.
Wooden Churches, Poland
In Poland, wooden church were found to be particularly at risk. Between 1999 and 2000, 50 churches burnt down. The most frequent cause of fire is not damage to electric installations, but a fire lit deliberately. Poland has a substantial amount of sacred wooden architecture, which make an important, often unique, contribution to European heritage. It consists in part of wooden churches, built between the C14 and C19, mainly Catholic, but there are also other churches, including Protestant, Orthodox, Catholic-orthodox, Dukhobor, Jewish and Mariavites churches. Wooden religious architecture also includes chapels, belfries and morgues. The scale of the task is significant, given that presently there are 2,785 items of religious wooden architecture in Poland and six of them (from the C15 and C16) are on the World Heritage List.
The Arson Threat
It is difficult to be precise about the growth in arson globally due to statistical variations, but there is good evidence that in many developed countries arson is a growing problem. The CTIF Centre of Fire Statistics demonstrated that, in 8 selected countries [Canada, Germany, New Zealand, Russia, South Korea, Japan, USA and UK] between 1993 and 1999, intentional fires accounted for 18 percent of all building and structure fires. This represents a huge level of unwanted and unwelcome activity, given the fact that a significant part of any country’s built environment contains numerous heritage sites (in some major cities like Edinburgh, Venice, and Rome the figure is very high) and that certain property classifications (like religious buildings) are subject to regular attacks of the sort identified earlier. To illustrate the growth trend in the UK, according to the UK Arson Prevention Bureau, the incidence of arson in occupied buildings has steadily increased over the past decade, as shown in the following Table.
Arson is now one of the most serious threats to heritage buildings throughout the world. The reasons for this form of attack vary enormously, from economic fraud to cultural disaffection. The nature of the attack can likewise arise from sophisticated fire raising by criminals using science and technology, to sudden unplanned attacks by vandals using any locally available materials. The impact however, regardless of the initiating event, may be the total loss of all the physical property both of contents and structure. The following real examples illustrate that the target can be a high-profile internationally-known building or a more generalised category of building-type. They serve to illustrate the task being confronted.
Whilst there are many documented causes and solutions to the arson threat, there are also particular circumstances related to heritage buildings that raise the risk presented from intentional attacks. For example, historic structures may
• Contain or be constructed in materials particularly vulnerable to fire, like wood
• Elements of structure will contain voids due to adaptations that spread fire and its products
• Modernisation may hide building services and associated features or structural elements that heighten the risk of undetected initiation or early structural failure
• Transfers and unclear ownership may lead to poor risk management
• Economic and funding priorities sometimes prevent investment in mitigating passive or active systems of fire defence
• Hazardous materials may be present on industrial or military heritage sites
• Criminal activity such as smuggling or theft may give rise to arson to cover the original crime
There are many documented responses to combating arson that suggest there is a strong onous on the heritage community to develop a sustainable and internationally-supported strategy to help preserve the national heritage of each country.
This is especially so when it is realised that within the European Union there are few special requirements placed in law on heritage buildings. A recent study supported by the European Union Community Action Programme in the Field of Civil Protection coordinated by Raddnings Verket, the Swedish Rescue Services Agency, found that no heritage-specific fire safety legislative requirements were in force in Austria, Belgium, Denmark (except a 5 yearly inspection), Finland, Germany (other than a building permit for certain uses), Greece, Sweden, The Netherlands (subject to some heritage and safety controls) and the UK. In Ireland, Italy and Norway, guidance or in Italy’s case technical controls, exist.
The proposal, therefore, is that the Cost Action C17 Working Group 3 should consider extending its investigations into the area of arson reduction and protection. This will require research into national statistics, identification of the national risk profile and subsequent identification of preventative action. Whilst there are cultural and national variations in the risk presented in any approach, there is high value in sharing best practice to help improve sustainability and add intelligence to create an effective response to what is an increasingly alarming threat.
In the earlier section, threats arising from vandals, criminals and activists have been described. Unfortunately, it is now necessary to add to that form of attack the increased threat of extremist action from disaffected groups in society. Prior to 11 September 2001, it was the case that the number of lethal terrorist incidents in Europe had declined, although the total number of incidents rose. The escalation of the terrorist incidents that had occurred in Europe and Eurasia were, in fact, often acts of arson or vandalism. However, terrorism has become an increasingly worrying threat to all those responsible for national icons or places of large public assembly. This, in part, reflects the paradigm shift that occurred in New York when vehicles like aircraft became weapons, instead of buildings being defended against weapons. Major sites that have crowds offer the terrorist anonymity and are internationally recognisable. Frequently, they offer hard construction materials that cause maximum personal damage and lead to economic losses, including tourism. They have become the new targets. Well-known and frequently visited heritage buildings and sites that fall into this category are therefore susceptible. In addition, security measures at higher-risk sites like government centres, can serve to move the terrorist further away from the obvious iconic or transport centres to softer geographically open locations. It is, of course, important to retain a sense of perspective. Lethal events are often infrequent, and in comparison to the routinely accepted loss of life in any country, are of a low order of magnitude. Usually, the risk is simply disruptive, as with left luggage (one example is 2.5 million emergency calls to unattended bags in a 10-year period in a transport environment, with no active explosive devices found). Society, however, demands active consideration of this threat and positive action to reduce both the possible occurrence and mitigate impact. This demands a sensible and systematic review of the likelihood and practical measures. In many areas action taken to reduce prevalent and active life-threatening events such as fire and security, will coincide with action designed to contain this extremist threat. There are many previous examples of this type of attack, especially where intolerance has existed, when individuals over generations have attempted and sometimes succeeded in destroying artefacts or symbols that they consider represent that intolerant burden.
Currently trans-national ideology based upon an Islamic fundamentalist cause that is globally, not geographically, regionalised, together with localised extremism, is seen as the new threat. This, some commentators suggest, is a misunderstanding of a threat that in reality comes from local groups that may share a common ideology, but act independently and in sympathy, without any central direction or control. Personal relationships and sympathetic supporters therefore form the basis of the unstructured network of loose alliances. This is considerably different to the earlier, and in some cases still current, more usual form of threat, in which the perpetrator belonged to an organisation that wanted to find a balance between mass innocent casualties and its political aim. That form of terrorist attack was often characterised by a warning and the terrorist seeking to escape and survive.
The economic cost of mounting a terror attack is low, yet the economic impact can be extremely high. Reducing the risk is also difficult from the perspective of vigilance, since the defender has to be systematically in advance of the terrorist, who needs only one success. This is a problem that some observers say will remain a real issue for some time, with terrorism of this kind expected to last the next 20-30 years.
Again, the practice of risk evaluation supported by sound policy and practice is the key. Co-ordination of best practice, education, investigation, advice, crisis management, business continuity planning, threat monitoring and risk assessment are all required. Technical issues that arise include the threat to people and contamination of the heritage site or workplace, physical violence, and detection of weapons and malicious actions. The identification of specific high-risk sites and event scenarios, like those affecting faith premises as already observed in acts against Muslim and Jewish places of worship, is priority action, since in this threatening environment, physically high levels of protection of all sites is impractical.
Intelligence, and the recognition of connections attributed between causes (as with the desire to see the USA leave Islamic countries or resolve the Palestine issue) are important features to research and understand. Whilst these are simplifications, they do serve to raise the matter as an important concern for those who have a responsibility to protect national heritage.
There is a real and urgent need to evaluate the risk presented at heritage sites from malicious acts of vandalism, criminal attack and local or international terrorism. Many of the issues have common features. There would be a benefit in gathering intelligence and knowledge collectively. That task could be an extension of the current role of the COST Action C17 activities. The proposal would require modest financial support, to initially scope the issue and to prepare a more definitive action programme bid, seeking financial support from the European Union.
Report on a Fire Test of a Ceiling in a Georgian Dwelling House on 2 March 1967, published in the Cost C17 Final Report vol 2 (pages 73-80)
RF Little, Chief Building Inspector, Bath City Council
Note that many of the technical testing methods described in this report will now have been superceded.
The test was carried out by Bath City Council under the supervision of the Chief Building Inspector of the City Engineers Department and the Senior Fire Prevention Officer of the Bath Fire Brigade. Observers form other authorities included
• Mr WH Cutmore, Ministry of Housing and Local Government
• Mr PMT Smart, Ministry of Technology & Joint Fire Research Organisation
• Mr Gibbs, Home Office, Fire Prevention Department
• Senior Building Inspectors from neighbouring authorities
• Senior Fire Prevention Officers from neighbouring authorities
At the time of the test (1967), no amendments to the English Building Regulations Part E had been made. The Regulations referred to are those current at that time.
Reason For Test
With the need to provide more units of accommodation, many large multi-storey houses previously occupied by one family were being converted into separate dwellings. In most cases, it was impossible to comply with the degree of fire resistance required by the Building Regulations, or the provision of non-combustible elements of structure. It therefore follows that applications for relaxation or dispensation of the Building Regulations were sought in the majority of cases.
In a building of three or four storeys which was to be converted into flats or maisonettes, if alternative means of escape could be achieved at parapet or roof level, and the main means of escape was protected by walls and doors having half hour fire resistance, it was considered that the provisions of Building Reulgations E5, E9 (7), E10 and E12 were unreasonable for the following reasons
• A ceiling consisting of at least 1 inch thick plaster on laths, with square-edged flooring over joists 2 inches thick, will provide half hour fire resistance, which is a reasonable time for vacating the rooms of a building in case of fire
• The British Standard 476 Fire tests on building materials sets out conditions which are far more severe than those actually experienced in a room of a dwelling when a fire occurs
• Compliance with the Regulations would not be possible, economically or structurally, in this type of building
In order to test this theory, it was necessary to simulate the behaviour of a typical domestic fire, from the time of ignition, through the build-up period, for at least 30 minutes and then having extinguished the fire, to examine the condition of the ceiling and the floor above, and having established that the theory is correct, to use such information to support future applications for relaxation of the Building Regulations where similar conditions occur.
The house chosen was No.12 Chatham Row and was an end-of-terrace house, built about 1760 and comprising a basement, with an open area at the front, to one side and to the rear, and three additional storeys. The external walls were of 5 inch thick Bath ashlar stone. The interiors of the rooms were lined with timber panelling to a height of 3 feet above floor level and plastered above.
The wall separating the ground floor room (the one under test) and the entrance passage was constructed of lath and plaster on a timber studding.
• The floors were seven inch by one inch square edged flooring on eight inch by two inch joists
• The ceilings were constructed of one inch plaster on laths with ornate cornices
• The roof of timber trusses and rafters with slate covering
• The house on plan measured twenty seven feet by eighteen feet, while the room (the ceiling of which was under test) measured twelve feet, five inches by thirteen feet and was nine feet high
Measures Taken Prior To The Test
A visit was made to the Fire Research Station at Boreham Wood to ensure that the test would be similar to tests carried out by the Joint Fire Research Organisation (JFRO), and the preparations were made strictly in accordance with the advice given at that visit.
Firstly, the room was brought up to the standard one would expect to achieve after conversion, except for decoration, and this entailed the following work
• Reglazing the windows and replacement of sash cords to enable the windows to operate normally
• Testing the key between the ceiling plaster and the laths, and infilling cracks in the plaster
• Replacing floorboards in the room over the test room
• Re-floating a concrete hearth in the room over the test room
• Covering the partition wall between the test room and ground floor passage with quarter inch insulation board and plasterboard to ensure half hour fire resistance
• Infilling the door panels and covering the whole internal surface of the door with quarter inch insulation board to give half hour fire resistance and increasing the door stops to a thickness of one inch
In addition, it was necessary to provide a suitable fire load, and the JFRO indicated that it was desirable to have a fire load of five to six pounds per square foot of floor area. Better results would be obtained if this was provided by cribs of rough cut timber rather than by articles of furniture.
Four cribs were prepared. Each crib weighed 216.67lbs. which gave a fire load of 5.67 lbs. per sq. ft. of floor area. In addition to this imposed fire load, each wall had the original panelling to a height of 3 inches above the floor level.
The floor covering was removed from the floor of the room over the test room with the exception of a narrow strip of standard hard board covering a crack between two floor boards. It was essential that the temperatures during the test were accurately recorded and accordingly five thermocouples were installed in the ceiling of the test room to record the temperatures at a position 3 inches below the ceiling at intervals over the area of the ceiling.
Arrangements on the Day of the Test
Recording instruments, to which the thermocouples were connected, were installed in the first floor rear room. The floor of the test room was covered all over with 1” of damp sand and at the points where the cribs were to stand, sheets of insulation board were placed on the sand. These measures were to ensure that the fire would not burn downwards and affect the floor structure. Four cribs were set up in the test room in the positions shown on the plan.
The ignition pyre was built at a central point between the four cribs and trails led away to the cribs. The pyre and trails were of wood shavings, wood chips and sawdust and was 1’ 6” high and the trails 6” high. Immediately prior
to the ignition of the pyre three pints of paraffin were poured on the pyre to simulate similar conditions to that of an overturned oil heater. The Fire Brigade Officer assumed responsibility for fire control during the test and also provided observers to record conditions during the test.
The test required that the temperature at five points, 3 inches below the ceiling, of the test room, should be measured at short intervals from the time of ignition of the fuel, affording the fire load, in that room. Thermocouples were used and the wire selected was nickel-chromium/nickel aluminium T1/T2.
Duration Of Test
In order to simulate as near as possible the conditions and development of a normal fire in a dwelling, it was decided to allow the fire to burn 45 minutes from the time of ignition. The reasons for this period being chosen are as follows
• In a normal domestic fire with oxygen supply limited to that found in a room with doors and windows closed, severe smoke logging occurs at an early stage and the fire could be self-extinguished through lack of oxygen. Under these conditions the ceiling of the test room would not be given a satisfactory test as maximum temperatures would not be reached. Therefore, a flow of air to the fire had to be guaranteed in order to ensure it would continue to burn. Accordingly, a 2 ½” gap was left above the top sash window from the beginning of the experiment and at zero + 3 minutes a gap of 3” was opened at the bottom of the lower sash window. This was at zero + 9 minutes, increased to 6”. During the whole of the experiment the normal flue from the grate of the room was providing a cross draught.
• As the structure of the ceiling was to be tested for a period of at least 30 minutes under normal conditions appertaining at a domestic fire, and at the end of the first 15 minutes approximately, of such a fire, it is usual for a ‘fall off ’ of temperature to occur until the fire is ventilated in some way, e.g. breaking of glass in a window, it was decided that the 30 minute period of test for the ceiling should take place after that initial 15 minutes period has passed. This meant that from the time of ignition of the pyre, to the time of completion of the experiment, a 45 minute period was indicated.
• Although, in some circumstances it would have been desirable to allow the fire to burn until the ceiling under test had collapsed, in this instance it was necessary to submit the ceiling to the heat from a normal domestic fire for a period of at least 30 minutes and then, if the ceiling still remained intact, to extinguish the fire and carry out a close examination of the fire damage done to the materials forming the construction of the ceiling and the floor above.
• The door and the partition wall, between the Test Room and the passageway from the staircase to open air, had been modified to conform with normal half hour fire resisting standards. A 30 minute fire test was, therefore, demanded and again the extra 15 minutes initial burning period, appeared to be indicated in order that the performance of the door and partition could be measured against that of the ceiling.
The day was dry with cloudy and bright periods. There was a slightly westerly wind. The front window of the room under test, faced west.
Summary Of Test
Zero: At 1205 hours the incendiary materials forming the ignition pyre and comprising wood chips, wood shavings and sawdust over which 3 pints of paraffin had been poured were ignited. When reference is made to this time in the following report it will be as ‘zero’.
Zero + 2½: Within the first 2½ minutes the pyres and trails were burning well, with some build up of heat and then smoke became quite dense as oxygen in the air within the room was rapidly reduced.
Zero + 5: At zero plus 5 minutes some temperature reduction showed on the thermocouple readings and a very slight percolation of smoke occurred at the top of the half hour fire resisting door, into the passage. The window at this point of the room was opened 3” at the bottom in addition to the 2½” at the top, in order to encourage air circulation. The cribs were now alight at the bottom. Quite heavy smoke logging of the room was apparent but the cribs were still visible.
Zero + 7½: In the next 1/2 minutes (zero 5 – 7½) the top pane of the front window cracked in two places and all cribs were alight at the inner corners with smoke issuing from the tops. Temperatures started to take an upward curve.
Zero + 10: Temperatures continued to rise and a slight increase of smoke penetration was noticed around the top of the half hour fire-resisting door. The front window was opened another 3” at the bottom ( 6” in all) and flames were noted coming from the tops of the cribs at all inner corners. Vision across the room improved.
Zero +12½: Continued rise in temperature. First signs of smoke on first floor – very slight percolation between the fireplace and the door, at base of wall. Cribs now burning well on inner surfaces. Side window glazing very hot.
Zero + 15: Temperatures still rising. Highest recorded at No. 3 thermocouple 3270 C. Smoke percolation at 1/2 hour fire resisting door very slight. Small increase in temperature of door panels. Lower pane of front window cracked. Cribs burning well with flames 2’ 6” high from inner surfaces. Good vision most of room but ceiling obscured by smoke.
Zero + 17½: One thermocouple showed slight decrease in temperature recorded (No. 5) others a slight increase.The Yale lock on the half hour fire resisting door, hot but bearable to touch. Slight percolation of smoke around the door jamb. Molten paint dripping from framework of front window and top pane cracked in the side window.
Zero + 20: Slight decrease in temperature readings of thermocouples 1 and 3. Increases on all others.Yale lock too hot to touch. Smoke becoming dense inside room and flames less visible, but cribs showing increased burning.
Zero + 22½: Increase all round in temperature recordings of thermocouples. Increase in smoke percolation around door stops and door jambs. Cribs well alight nearest door. Increased number of cracks in front top window. Severe discolouration of side window by smoke.
Zero + 25: Temperature reading of centre thermocouple (No. 3) same as zero + 22½ . Slight decrease in reading from
No. 5. All others slightly up. First signs of smoke through cracks between floorboards at a point immediately above the partition wall between the test room and the passage. Slight smoke also showing in corner of room at side of the door. Again over the passageway. No apparent increase in temperature of the half hour fire-resisting door frame but slight increase evident on panels. Fire in cribs sluggish. Sash cords to lower half of front window burnt through and window dropped. Glass only slightly broken away and a reduction of visible flame with a corresponding increase of smoke evident.
Zero + 27½: Considerable drop in temperature readings of thermocouples 1, 2, 3, & 4. Slight drop in case of No. 5. Smoke now coming through crack at end of another floorboard over the ground floor passage and some percolation of smoke into the Recording Room, first floor, rear. No smoke coming from around the door stops and jambs. Pegs removed from below top section of front window to simulate sash cords burning through. Window dropped and glass dislodged where cracks had already been apparent. Smoke seen to be issuing from cracks in walls and lintel over the side window.
Zero + 30: Sudden rise in temperature recording of all thermocouples other than No. 5. Smoke now increased from the base of both door jambs near landing at first floor level and also issuing in centre of room near the thermocouple (No. 3). Very slight smoke percolation around the half hour fire-resisting door. Flames in the room high and licking the ceiling. Slight flaking from ceiling, possibly distemper or similar decorative material. Bottom pane of glass in side window cracked.
Zero + 32½: Steady increase in temperature recordings of No. 1-4 thermocouples. Slight decrease in temperature recorded at No. 5. Smoke convected from window of room on fire below, through the unglazed first floor window. Signs of smoke from the top of the wooden wainscoting near front window. Paint softening on the top rail of the half hour fire-resisting door and smoke issuing under pressure from the Yale lock. Smoke also apparent from between the top of the door and the door stops. Cribs well alight and tops of window frames and frame around window opening burning.
Zero + 35: General rise in temperature recordings. In the case of No. 2, 3, 4, 5 from 800 C – 1050 C, and No. 1 a very slight increase of 60 C. At first floor front room level considerable smoke percolation was apparent from around the sill of the front window. Smoke also percolating between the skirtings and the floorboards all along the wall between the front room and the centre of the room. The paint on the panels of the half hour fire-resisting door started to blister. The top pane of glass in the side window blown outwards by excessive pressures in the test room.
Zero + 37½: Rapid rise in temperature recorded. In the case of thermocouple No. 5 – 2260. Following a crash of glass breaking (side window – see Zero + 35) the smoke and heat entering by the first floor front window became less. Some smoke started to come up the staircase. A greater quantity of smoke apparent through the Yale lock on the half hour fire-resisting door and smoke around the door increased.
Zero + 40: Continued rapid rise in temperature recordings. 3200C in the case of thermocouple No. 1. Smoke percolation continued at first floor front room level and fire observed for the first time at the side of the front window. Heat through the unglazed windows, rising from the room below became intense. A slight increase of smoke noticeable from the upper area of the door around the stops. Fire in ground floor room at peak with plenty of ventilation by way of the two windows which were now without glazing. Slight flaking of ceiling is still all that is apparent. No breaking down of separation.
Zero + 42½ : Highest temperature reached No. 3 thermocouple, 10000 C. All others, 8950 C. or above. Fire still at its peak. Half hour fire door shows slight burning at the top. Upper panels still comparatively cool. The ceiling of the room was intensely white and appeared to be glowing. No signs of failure.
Zero + 45: Temperature still between 8430 C and 9870 C. The latter being the measurement at No. 3, thermocouple. Most smoke percolation at the first floor front room was between the chimney breast and the door. Smoke percolation also quite heavy around the base of the wainscoting panelling on the wall between No. 12 and No. 11 Chatham Row. Inspection afterwards showed that this smoke had entered the hollow partition wall around the door at ground floor level and had then risen into the void between the ceiling and floor above which was situated over the passage. The room was now becoming smoke logged. The half hour fire-resisting door was starting to warp at the top allowing smoke to pass more freely. The whole of the ceiling still apparently sound. None of the stopped in cracks had broken down. Cornices still in position. Fire still extremely hot but showing signs of being past its peak.
Zero + 45½: Temperature reading No. 1 thermocouple -7650 C, a fall of 1750 C. Ceiling still apparently sound.
Zero + 46: Extinguishing of the fire commenced using 1” hose reel jet. This was augmented by 1/2 “ jet. Steam produced, caused rapid cooling of the surface of the ceiling, and the first cracks appeared. These seemed to be in positions where original cracks had been repaired. Approximately 8 sq. ft. of ceiling then fell away and access of air to the ceiling void and exposed laths resulted in some of the laths, already conditioned by conducted heat, catching on fire. Extinguishment was carried out without undue disturbance of tested material, but water hitting the door surface caused the asbestos fibre board surface to split and curl. This same effect was produced where water hit panels of asbestos fibreboard which had been fitted over recesses which were suspected of not being up to half hour fire-resisting standards. The plasterboard covering the partition wall was damaged considerably during extinguishing because fire had entered the hollow partition and water had to be directed through into the hollows at various points causing spalling of the plasterboard and plaster of the partition itself.
Observations during the test.
The ceiling under test registered the passage of flame for the whole of the test period of 45 minutes. There was no sign of cracking, distortion or material breakdown during the whole of the test other than a brief period, in the early stages, when some initial flaking occurred on some parts of the surface of the ceiling eg distemper. The fire had reached its peak at zero + 42½ and then the temperature curve had started to descend. At the peak period it was noted that the fuel cribs in the test room were almost exhausted having burned down to within 6” of the floor. It is, therefore, reasonable to assume that a continual drop in recorded temperature could have been expected had the fire been allowed to burn after zero + 46. The treatment of the inner surface of the door and partition, between the ground floor passage and the Test room, to afford half hour fire-resistance was completely successful in spite of the fact that the plasterboard additional covering had not been skimmed with plaster to seal the joints. The penetration of the fire which did occur into the hollows of the laths and plaster partition over the door, was not through the protected surface but by way of the architrave over and to the side of the door opening. The fire thus by-passed the protection. Even so this must have occurred at the very late stages of the test as no flame was noticed on the floor above until extinguishing the fire in the test room well under way. It was then necessary to remove some of the lath and plaster surface of the partition in order to extinguish the hot spot.
At no time during the whole of the test was the escape route from upper floors so affected by smoke or heat that it could not be used. The separation afforded by the half hour fire-resisting partition wall and door was adequate for the whole 45 minute period of the test. Although some smoke percolation occurred past the ends of floorboards in the front room at first floor level, no flame penetrated at any time through that area of the floor over the test room. Considerable pressures were applied by hot gases both to the ceiling and the walls. This was most evident at zero + 32½ when smoke issued in the form of a horizontal jet from the Yale lock on the door, and at zero + 40 when the glass of the upper sash window at the side of the test room blew out with considerable force. The fire followed the usual pattern which can be expected when a fire occurs in a room in domestic property in which there is a normal fire load, the fire has some ventilation and is not disturbed for some period by opening doors or breaking windows. In the case of this test there was an early rise in temperature, brought about by the paraffin soaked pyre burning fiercely and then as the cribs became involved and oxygen in the atmosphere of the room became rare, a sluggish period followed. This occurred during the first ten minutes after which, by increasing the flow of air over the window sill of the front window, more rapid combustion took place. A gradual rise in temperature for a further 15 minutes when again some smoke logging developed and temperatures dropped. This was at the time that sash cords burnt through, which were holding up the bottom section of the front window. When the top window section was dropped the new supply of air stimulated the fire and a general very rapid rise in temperature resulted culminating in the peak of 10000C. being reached at zero + 41½. Fuel was at this time becoming exhausted and in the next 2 minutes a decline in temperature commenced. The heat of the test fire was sufficient to cause almost all of the 11/4” plaster skimming on the inside of the front wall of the room to leave the stonework.
Observations after the Test
The ceiling under test withstood the application of heat from a normal fire load underneath for the whole of the 45 minute test period without any visible signs of deterioration. No cracks were apparent, and after the initial flaking of surface decorative materials no further spalling or flaking was noted. The plaster cornice around the room also remained intact, other than in one short section immediately above the front window where it cracked and dropped slightly.
When water was applied to the fire in the remains of the cribs, the steam created caused, after approximately halfminute, sudden contraction of the ceiling and cracks opened up at points where previously cracks had been undercut and sealed with plaster during the preparation period. A few moments later approximately 8 sq. ft. of ceiling plaster fell to the floor. It was noticed that although some of the laths had carbonised due to heat conducted through the plaster they were not on fire, but as soon as they were exposed small flames appeared on the carbonised surfaces. These had to be extinguished to prevent further damage and during the extinguishing, further collapses of ceiling plaster took place.
With greater exposure of the underside of the floor and the joists it was most apparent that the floorboards were undamaged and the lower edge of only some of the joists, although charred in places, the charring was not of sufficient depth to measure with any accuracy. A considerable portion of the laths still remained undamaged.
A composition gas pipe passing through the void between the floor and the ceiling was undamaged. In addition, an accumulation of small twigs and fibrous material, possibly collected by mice and in itself readily combustible, found in a void between floor joists, resting immediately on top of the laths supporting the plaster ceiling, was not damaged in any way by fire or heat. The plaster decorative cornice around the room was intact after the fire on three sides of the room. In the case of the fourth side, it was only the section immediately above the front window that some signs of damage occurred. At this point the cornice cracked vertically and a section approximately 18” long dropped slightly but did not become dislodged.
Although during the whole of the 45 minutes covered by the test, some smoke did percolate into the passage and also into the first floor room above the test room, at no time was the movement of people prevented along the passage, up the staircase or around the rooms.
The fire, during the period of the test, did not penetrate the ceiling and floor structure to the room above. At zero + 58, after extinguishing had commenced, a small flame was noticed at a crack between floorboards which had been covered with a strip of standard hardboard. The hardboard was burning and flame started to travel rapidly over its surface. When the source of the flame was investigated it was found that the fire from the test room had penetrated the architrave of the door at a point over the top of the half hour fire-resisting door, and had then by-passed the ceiling of the test room by travelling up the hollow of the partition wall. This was also the route by which most smoke percolation occurred into the first floor room.
The partition and door which were converted to half hour fire-resisting standards stood up to the test remarkably well. Some percolation of smoke and heat by-passed the test ceiling by way of the hollow partition. This, however, would possibly not have occurred, had the partition been skimmed with plaster and cracks filled in accordance with normal procedure.
The door reacted extremely well. It was only at zero + 45 that the door began to warp and allow smoke to escape in increasing volume. When the remains of the asbestos fibreboard cladding was removed from the inner face of the door including the panel infills, some of the original green paint was still intact under the infills.
The fire resistance of a normal ceiling in a middle class Georgian house is such that it is capable of preventing fire from spreading to the floor above for at least a 30 minute period. It is normal for vertical separation between rooms and exit routes to afford half hour fire-resistance. To be consistent, therefore, a ceiling between such rooms and rooms above should also be half hour fire-resisting and a fire resistance of one hour plus, as required in some circumstances by the building Regulations 1965, between floors, would appear to be excessive. It would appear that the tests applied under furnace conditions to ceiling and partitions, to assess fire resistance, is too stringent and does not simulate conditions as they really occur in a fire in a building. Under the circumstances it would appear that the fire resistance of a sound Georgian ceiling does not require to be upgraded to one hour. Such an upgrading could result in the fire below the ceiling breaking out horizontally into the exit route and preventing escape by that route, before any warning of a fire is transmitted to persons living above.
Mr. A. E. Loveridge (then Chief Building Inspector, City of Bath)
The Chief Fire Officer, Bath Fire Brigade.
The Principal, Bath Technical College.