Peter Barker, Senior Consultant at Chiltern International Fire externallink, outlines the issues and offers practical advice on managing the fire risk in historic buildings.

Introduction

Under the requirements of the Regulatory Reform (Fire Safety) Order a suitable and sufficient fire risk assessment (FRA) is required for all premises other than private dwellings. For historic buildings it is of paramount importance that a well structured and properly implemented fire safety management plan accompanies the FRA.

In fact it is recognised in Approved Document B (ADB) that the most appropriate means of ensuring life safety in an historic building with respect to fire, is to take into account a range of fire safety features and set these against an assessment of the hazard and risk peculiar to the particular case.

The essential components of an FRA and fire safety plan for a historic building can be broken down into four steps: preparation, prevention, protection and management. There is no standardised format for recording or presenting the findings of a risk assessment or safety plan, but in every case the goal should be to produce clear and comprehensive documentation that is regularly reviewed.

Preparation - Before undertaking an FRA it is necessary to obtain accurate plans of the building, as this will not only save time and effort in the long run, but can also be useful when preparing business continuity plans, inventories of artefacts, cleaning regimes and security assessments.

Ultimately it will be the building plans, with relevant and up-to-date information on hazards, fire fighting equipment and salvage strategies, which will form the basis of how the fire and rescue service will respond in the event of a fire.

Prevention - Preventing a fire in the first place is the obvious ideal situation and is the first stage of physically assessing the risk of fire within any building. By identifying ignition sources and flammable materials and either removing them or introducing alternative methods of storage, the fire risk will be greatly reduced.

Identifying measures to reduce the risk of fire in historic buildings makes eminent sense, as remedial measures can often be put in place almost immediately. Some approaches can be relatively inexpensive and involve minimum intervention in the fabric of the building.

Relevant questions to ask when looking at preventing fire within a historic building could include the following (not exhaustive):

  • When were the electrical circuits last tested and have all appliances both fixed and portable been tested for safety?
  • Are all drapes/curtains/tapestries a suitable distance from potential ignition sources (such as halogen lamps)?
  • If smoking is allowed outside the building, have adequate precautions been taken e.g. dedicated smoking shelters located away from the building?
  • Are waste and/or flammable materials appropriately stored?
  • Is there significant threat from arson and can it be deterred?

Protection – Once the risk of fire has been mitigated as far as practicable, protective measures need to be introduced to safeguard occupants, the property and important artefacts in the event of fire.

Although the guidance in ADB can be unduly restrictive for historic buildings, the philosophy behind the five sections (B1 – B5) of Part B of the Building Regulations comprehensively covers all aspects of fire protection within a building. Therefore, by dealing with each of the requirements in turn, and introducing practical solutions suited to the building and its contents, a holistic fire safety strategy can be developed that will not only satisfy the functional requirements of the building regulations but ensure a safer environment for occupants, reduce the risk of fire and minimise the impact of fire should one occur.

Protective measures are often controversial because they can be disruptive to the original fabric of the building, and the physical installation of the systems can sometimes be difficult in a heritage building.

It is possible, however, to take suitable protective measures that are sympathetic to the historic fabric of the building, but which can also be designed for individual premises. It is highly recommended that a third party-approved company with a proven track record of installations in historic buildings is chosen for this.

Examples of protective measures, their relationship to the five sections of Part B and common issues and potential solutions with respect to heritage buildings are given below:

Building Regulation requirement Common issues in heritage buildings Potential solution(s)
B1 – Means of warning and escape
  • Room geometry can render British Standard recommendations for use of detectors unsuitable
  • Large windows or ornate ceilings can allow a large flow of air over detectors preventing them from responding quickly enough
  • Installation of systems disruptive to historic fabric of building
  • Escape routes longer than that recommended in current guidance
  • No alternative exit in certain parts of building.
  • Careful selection of detectors can greatly improve the chance of detecting a fire before it becomes too large. Beam detectors can cover large areas with relatively few detectors and reflectors therefore reducing the disruption to the fabric of the building. Wireless systems are available that can be used in areas of a historic building where the installation of wires is not acceptable or possible
  • ‘Hidden’ aspirating detectors have been used in historic buildings where by the detector head is concealed within a wall or ceiling and therefore minimises aesthetic impact. Further to this, aspirating detectors continually sample the air and will decrease the time it takes to detect a smoke signal
  • Focussing detection on higher risk areas, whether this is to safeguard areas that pose greater risk to occupants (extended travel times for escape, sleeping risk, people with special needs etc.) or protect areas of special historic importance
  • Linking the automatic fire detection to fire suppression systems, fire curtains and fire doors to ensure that the fire is isolated as quickly as possible
  • Introducing detection in areas of the building that could pose a risk from hidden fire spread such as floor/ceiling voids, redundant goods lifts/chimneys etc.
  • Training of staff to respond immediately to a fire signal and to begin implementing evacuation and artefact salvage plans will greatly increase available safe egress time (ASET).
B2 – Internal fire spread (linings)
  • Variation of linings – exposed brick, timber panelling, wall-hung fabrics
  • Enhancement of timber panelling/linings by surface applied fire retardant/ intumescent treatments affecting the aesthetics of the original fabric of building.
  • Re-positioning of wall-hung fabrics away from key circulation areas and escape routes will greatly reduce the risk of fire spread and smoke compromising evacuation from the building
  • Upgrading the fire performance of timber panelling (in terms of reaction to fire classification – class 0, class 1 etc.) in key circulation areas and escape routes to minimise the impact on the historic fabric.
B3 – Internal fire spread (structure)
  • Installation of fire stopping measures can involve removing ornate panelling and can potentially affect the airflow within a building creating problems with moisture and damp
  • Upgrading fire performance of doors and wall disruptive to historic fabric of building
  • Listed status of doors and panelling restricts upgrading and remedial work
  • Installation of fire suppression systems can be disruptive to the fabric of the building and water resources and tanks can be limited or difficult to site
  • The use of sprinkler systems can be damaging to valuable artefacts and archived objects/materials.
  • Taking care to install fire stopping measures at critical junctions with minimum disruption to the aesthetics of the panelling. If it is necessary to remove original or ornate features a restoration specialist should be consulted. It may also be worth taking advice from a historic building specialist as to whether the fire stopping measure will affect the airflow within a building creating problems with moisture and damp
  • Careful selection of methods for upgrading the fire performance of joinery doors in terms of supporting fire test evidence and impact on the doors aesthetics. If the available methods do not have suitable supporting test evidence or the impact of the method on the fabric of the door is deemed unacceptable, it may be desirable to commission an assessment in lieu of a fire test. Such an assessment can be used as a design appraisal of an existing doorset design so that a fire-rated copy can be constructed; the original can then be placed in safe storage for as long as necessary
  • Active suppression systems need to be carefully considered and designed with respect to the location of the sprinkler heads, pipes, water resource, the building and its contents to ensure it is able to control a fire should one occur
  • Ensuring availability of first aid fire fighting equipment and comprehensive training of staff in its use. The appropriate fire extinguishers and blankets, when used correctly, can tackle the fire at source and prevent it from becoming serious. First aid fire fighting equipment requires little or no interference with the fabric of the building
  • Use of an oxygen reduction system will avoid damage to valuable artefacts and archived objects/materials. If appropriate to the risk, a water mist suppression system will use considerably less water than a sprinkler system.
B4 – External fire spread
  • Risk of external fire spread predominately applicable to buildings with combustible facades – limited to working with existing fabric of building, options for upgrading fire performance is limited.
  • Surface applied treatments for timbers are available but are restrictive for external applications because they will need re-applying on a regular basis due to weathering effects – UV degradation and freeze-thaw
  • Water mist suppression systems have been used to shroud a building in water mist to prevent fire from engulfing it, such as: wooden churches, parts of buildings such as thatched roofs and historic timber ships.
B5 – Access and facilities for the fire brigade
  • Access for fire tender vehicles can be limited
  • Historic buildings can be remote from nearest fire and rescue service
  • Limited water resources (no fire mains).
  • Liaise with local fire and rescue service regarding access and facilities to develop and agreed ‘planned response’. If access to the building is restricted it may necessitate attendance by a different type of tender vehicle with specialist equipment
  • Use local resources such as lakes or rivers to supply water for the fire hoses rather than relying on a potentially inadequate mains supply
  • Accurate site plans with access points and other important information need to be supplied to fire and rescue service to maximise efficiency on site
  • Develop artefact salvage plans in co-operation with the local fire and rescue service.

 

Management - Once the FRA has been completed and suitable protective measures are in place, a robust management system in the form of a fire safety management plan must be drawn up, as poor management can render the most comprehensive risk assessment and protective measures ineffectual.

Key points to incorporate within any fire safety management plan are:

  • Measures identified during the prevention step are regularly reviewed/revisited to prevent fires from developing
  • Maintenance schedules to ensure the protective measures put in place are still capable of performing as intended
  • Comprehensive and regular training of staff in evacuation procedures, raising the alarm, first aid fire fighting and salvage plans
  • Emergency drills must be performed and any shortcomings recorded and rectified as soon as possible
  • Periodic review of the risk assessment and fire safety management plan, especially after a change in use of the building or a 'near-miss' incident.

A business continuity plan should be integrated within the fire safety management plan so that in the event of fire, restoration work can proceed as quickly as possible. Being prepared for an emergency will significantly improve recovery rate.

Conclusion

Safeguarding our heritage from the ravages of fire should be considered as conservation of our historical record for future generations. Provided that there is co-operation between all persons with a vested interest (e.g. building owners, the fire and rescue service, fire safety consultants, historians, architects, staff and visitors), historic buildings and the treasures within will be preserved and enjoyed for many years to come.