19thurs 10-50 tu

YF TU / G TIMMS / M DIMASCIO / A CHAU 1 / 21

CORRECTIONAL CENTRE AND DETENTION CENTRE FIRE SAFETY DESIGN

Y.F.Tu1, G.Timms1, M. DiMascio2, A. Chau3

1 Fire Engineering, Arup, Brisbane, QLD, Australia 2 Fire Engineering, Arup, Westborough, MA, United States of America

3 Fire Engineering, Project Services, Department of Public Work, QLD, Australia 1 INTRODUCTION

Fire safety design for correctional / detention centres (prisons) is challenging for fire engineers, authorities and operators. It requires all stakeholders during the design and approvals process to understand the challenges arising from the conflicting requirements for security verses fire safety. Some of these challenges that impact on the building design for this type of facility are outlined in this paper. The International Fire Engineering Guidelines (IFEG) provides a framework for undertaking a performance based design, and an aspect of the design process is to identify the fire scenarios, and subsequent design fires, upon which the design is to be based. Johnson et al [1] have discussed the development of fire scenarios for projects, and suggest a more robust and structured process for design teams to determine the fire scenarios and design fires for ‘design’, ‘high challenge’ and ‘extreme event’ scenarios. A key aspect of this approach suggested by Johnson et al is the proper analysis of the fire hazards as the forerunner to developing the fire scenarios. This paper examines the fire hazards associated with the design of a prison including the review of some statistics that have been published for prison fires in the United States of America (USA), Canada, and Australia. This data indicates that fires in prisons are reasonably common, and that a significant proportion are deliberate fires in the accommodation cells using mattresses and clothing as the fuel and smoking materials as the ignition sources. The data suggests that although there are a reasonable number of fires in cells, the fatality rate is quite low. However, use of this data has to be cautioned as the statistics from one country may not be directly applicable to another if the fire safety measures / systems are different between countries.


2 / 21 YF TU / G TIMMS / M DIMASCIO / A CHAU

Whilst the Building Code of Australia (BCA) [2] has no specific requirements for the design of prisons, other codes such as those in the USA and United Kingdom (UK) do provide design guidance on fire safety measures / systems which can aid in the development of a fire safety design for a prison. 2 DEVELOPMENT OF FIRE SCENARIOS

Johnson, P.F., Boverman, D., and Johnson, C.E., in their paper titled “Scenario Analysis in Fire Engineering of Major Projects” [1] present a structured approach to the development of fire scenarios for performance based designs. The paper indicates that some performance based designs represent only a minor deviation from the Deemed-to-Satisfy Provisions of the BCA (ie the ‘norm’) whilst other more radical or innovative designs are far from the ‘norm’ and are more challenging. They indicate that for designs close to the ‘norm’, fire engineers and certifiers are capable of developing appropriate fire scenarios and design fires for analysis of the building’s fire safety performance. However, for the more challenging designs, far from the ‘norm’, the fire engineer may not perform as well in developing appropriate fire scenarios and design fires for analysis, and that the consequences could be inadequate designs with potentially disastrous outcomes in a fire event. In their paper, they present the following framework (see Figure 1) for identifying all the fire scenarios and developing the design fires for analysis. The output of the process is three groups of fire scenarios; viz: • Design fires • High challenge fires (for sensitivity testing) • Extreme events (scenarios beyond design) They suggest that ‘design’ fires consider reasonable fire growth rates assuming all fire safety systems are operating and a substantial margin of safety. High challenge’ fires would represent fires with higher growth rates and failures of key fire protection systems, and in this case the aim is to test the sensitivity of the design and consequently a reduced safety margin could be considered. The third group is ‘extreme events’ that might involve multiple ignition sources, or multiple failures of fire safety systems, but the scenarios would not require quantitative analysis as they are considered beyond the design requirements.



Figure 1: Fire Scenario and Design Fire Framework

In the paper by Johnson et al [1], they suggest that a key element of the framework is the proper analysis of the fire hazards so as to then develop the fire scenarios. As shown in their framework, the hazard analysis requires a thorough understanding of the building occupants (eg prisoners), fire characteristics (eg cause and origin of fires, item first ignited, likelihood of spread), and hazard analysis / risk assessment (eg frequency and consequences of fires). Development of the fire scenarios will also require an understanding of the trial fire safety design and the fire safety systems to be provided in the building. In the case of prisons in Australia, the BCA provides little guidance on the fire safety design requirements and as such guidance from other codes may be warranted.



3 BUILDING AND OCCUPANT CHARACTERISTICS

Challenges that impact on the design of a prison include: 1) the inmates’ movement being restricted and locked in their cells, 2) staff are frequently unwilling to release inmates during a fire incident, 3) an inmate’s malicious and self-harm behaviours, 4) difficulty in carrying out maintenance/services to the installed systems, 5) the delay in Fire Brigade attendance time given a lot of the centres are not in the

metropolitan areas, and 6) limited staffing at times when fires are most likely. In a typical prison there are different classifications or levels of security to which the inmate could be incarcerated. Each prisoner is classified based on a number of criteria including their backgrounds, criminal history, the crime committed, their psychological state, character and behaviours, to name just a few. The security level classification could range from low to high, and there could be special areas within the centre with a higher level of observation or care where high risk inmates are housed. The inmates are accommodated into buildings that match their classification. The treatment of the accommodation buildings is different for each risk classification in order to suit the operational need of the prison. Each accommodation building will have its unique design and fire safety features to cater for the security level of the inmates. This paper will focus on accommodation buildings for the high security classification inmates. It could be expected that the lower the security classification, the higher the level of freedom one would have in the prison system and this is translated into the design of the buildings.

3.1 Restriction in Movement

The main difference in the fire safety design between prisons and any other types of residential occupancy is that the occupants are not capable of self-preservation actions as they have limited freedom to evacuate from a cell or a building, and have no access to fire fighting equipment. Unlike other accommodation buildings such as a hotel, the inmates in a detention facility do not have the liberty of leaving their rooms in certain hours of the day. There



are ‘locked down’ periods which typically range from 8.00pm to 7.00am in the morning. Some facilities could have a locked down time during the day for mustering /roll marking and other purposes. During this time the prisoners are locked in their cells and they cannot leave their cells until the doors are released by the officers. When they are not locked in their cells, the prisoners are generally confined to a building. Again, they can only leave the building with the permission of the officers and after the doors are released. In a fire emergency, the prisoners would rely on the officers to unlock the cell doors and then the building before they could reach an area of safety. Therefore, there are obvious differences in this type of facility to other residential buildings. The overall fire safety design strategy of a detention facility must consider the restrictions in leaving the immediate danger areas of the building and then evacuating from the building to a place of safety. At the same time, the officers need to maintain control of the inmates and the situation. To maintain control, there will be times when the staff could be reluctant or unable to release the prisoners from the cells. The staff would need to determine the condition of the cell, if the inmate(s) is in immediate danger, the officers’ own safety, whether to wait for the arrival of reinforcements/assistance and other reasons. This delay would depend on the time of the incident, the ‘mood’ within the building, staff to prisoner ratio, and the security risk posed to the officers from the incident and/or the inmates. An example would be, the officers may be more readily to release an inmate from a low security area than the high security areas of a prison. The restriction in movement can severely endanger the inmates’ life safety. A recent fire occurred in an immigration detention centre at Schiphol airport near Amsterdam on the night of 26 to 27 October 2005, killing 11 people and injuring 15. An investigation paper published in the Interflam 2007 conference [3] has identified that the prison guards evacuated the inmates from the fire origin cell failed to close the door behind them, and the smoke/fire poured into the corridor. The locking devices to the cell doors were designed to be unlocked manually; however, due to the condition in the corridor, the prison guards were not able to open all the cells and left inmates in five cells. The investigation report identified one deficiency in the design is that the detention centre management failed to identify the fire risks in the facility and to set up an adequate emergency organisation able to control the risks. A



recommendation made in the investigation report is to consider self-closing cell doors and central unlocking of cell doors to provide robustness to the fire safety system.

3.2 Arson Fire

There is a high tendency for arson in prisons, and this can range from a fire in a cell through to a co-ordinated protest or riot where combustibles from multiple cells are combined to create a fire much larger than that anticipated for the occupancy. It can be demonstrated that smoke from any size fire could fill a cell and cause untenable condition in a very short time. This is particularly true if mattresses are involved, as these will give off a large volume of toxic smoke even with a small flaming fire. Other common combustibles used are paper, clothing, bed sheets and television sets. In general anything that burns could be used. Fire retarded mattresses have been used to reduce the potential fire load and the impact of a fire. However, this would not be sufficient by itself given the confined space of a prison cell. In response to this threat and to safeguard the inmates, early fire detection and other active fire safety systems combined with appropriate staff response strategies have to be developed to minimise this risk. The fire systems must have redundancies, be reliable and sufficiently robust to withstand tampering and interference from the inmates. To be successful, the response strategy must be tested and continually practiced to ensure its effectiveness.

3.3 Malicious Behaviour and Self-harm

To come up with the reasonable fire scenarios, it is important to understand the reason behind the deliberately lit fires. Carson [4] explains the motives for the malicious lit fire may include: • Increased chances of escape • Malicious damage as a protest against conditions • Show of force during a riot • Suicide attempt • Divert attention from other activities Another dilemma that arises with this type of occupancy is that the occupants may, in extreme situations, intend to harm themselves with the facilities that are accessible to them to attract attention. Dear [5] interviewed some prisoners who were involved in



self-harm incidents, and concluded that the four main motives for self-harming are: • Relief from psychological distress (40%), • Escape from one’s circumstances (32%; often with high suicidal intent), • To get someone to listen to them, or to be treated seriously (13%), and • To force a change in the prisoner’s circumstances (8%) One method of reducing the tampering of the systems inside a cell is to install equipment such as smoke sensors at a location out of the reach of inmates, in high ceiling areas or outside the cells. There must not be parts that could be easily dislodged from the system without raising an alarm. The system should have a high level of redundancy, to allow for the failure of the primary devices. In the design of these systems, one must be the devil’s advocate and think like the inmates for ways of defeating or destroying the systems provided. An example is the use of institutional sprinklers. These have been specifically design to minimise that risk of inmates using the sprinklers as a hanging point for self harm. However, the fact that the sprinklers are designed to ‘break’ under a moderate force also means that they become more susceptible to malicious behaviour and potential damage. The design must be able to overcome these issues before it can be put into service. In advancing towards this goal, the systems may not be able to fully conform to the Australian Standards and therefore have to be a modified system. Performance designs and real life test demonstrations may have to be carried out to demonstrate the desired outcomes could be achieved.

3.4 Difficulty in System Maintenance

The buildings and the systems in this type of facilities have to be “vandal resistant/proof”, “self-harm proof”, and “hang proof”, but reliable to ensure they could respond in an emergency. Any maintenance required to the systems can be disruptive to the operation of the facility and should be minimised as much as possible. It could also create a risk and affect the security of the prison. The on-going maintenance to the systems could also impose a budgeting issue for the state owned premises. The designer of the fire systems must appreciate the above issues and take them into consideration in the design process. Where possible, the equipment that requires



regular maintenance should be installed in a prisoner free zone to reduce supervision and allow greater free access for the maintenance personnel.

3.5 Delay in Fire Brigade Intervention

As many of the prisons are not situated in the metropolitan areas, the fire brigade could take longer to attend to a fire call. In addition, the security procedures required in a prison system especially during an emergency may further delay the intervention of fire brigade. This should be taken into consideration if the designer wishes to rely on fire brigade intervention as part of the fire safety design. In most of the Australian States, there is legislation governing the attendance of the fire brigade in prisons. Usually, the brigade will respond to a fire call but will not enter the facility without the centre manager’s permission. This is designed to protect the fire fighters, the prison staff and the inmates. Usually this permission will only be given after the inmates are under control and pose no danger to the responding personnel. Once inside the centre, the brigade is escorted to the fire to carry out their fire fighting operations. Some of the prisons may not have automatic brigade monitoring in order to avoid false alarm call outs. The call out of the brigade relies on the officers in the master control room pushing a call point which is connected to the brigade communication centre for the alarm notification. 4 HAZARD ANALYSIS

4.1 Australia

The Victorian Department of Justice document “Cell & Fire Safety Guidelines” [6] provides a summary of fire statistics for the period 1st July 1997 to 1st July 2001. This document indicates that there were only 5 major fires and no fire fatalities. There were 209 minor fires with known cause and 136 (65%) were deliberate. The majority of deliberate fires were located in cells. Most fires, irrespective of cause, tended to occur in maximum security facilities. This review was for the period 1997 to 2001. However, there have been at least two notable fires in prisons in Victoria that have resulted in fire fatalities. In 1982 a fire at Fairlea Women’s Prison resulted in the death of three (3) inmates. The fire in the dormitory was believed to be deliberately lit to highlight the poor living standards of the



prison which was originally constructed in 1957. Another fire occurred in Jika Jika in 1987 that claimed the lives of five (5) inmates. This was a deliberate fire lit during a protest and riot.

The NSW Department of Corrective Services [7] provided a summary of fire incidents for 2002 through to 2007 which indicated that there were 417 fires in the six year period, of which 272 (65%) were deliberate (rubbish, bedding, paper and clothing), 98 (23%) classified as ‘other’ (foodstuffs, electrical, rubbish) and the remaining 42 fires (10%) classified as ‘undetermined’. During this period there were a total of 61 inmate injuries (smoke, burns, self harm) and 21 staff injuries which corresponds to approximately 0.2 injuries per fire. The extent of these injuries was not defined and no fatalities were reported. Of these 417 fires, the NSW Fire Brigade attended 297 but only extinguished 50 fires (ie 12% of fires were extinguished by the fire brigade). The vast majority were extinguished by staff using either portable fire extinguishers or hose reels. The Queensland Department of Corrective Services [8] recorded a total of 26 incidents of fire, or suspected fire, in the 2005/06 financial year. Apart from 2 fires, the remaining 24 were relatively small and quickly extinguished. One of the two more significant fires broke out in a furniture workshop and within minutes 18 staff were on-site evacuating their colleagues and prisoners with some people suffering smoke inhalation and injuries. This fire was thought to have been deliberately lit. The other fire incident occurred in the kitchen area headquarters facility that was decommissioned and being retrofitted.

4.2 Canada

The fire statistics for Canadian prisons for the period 1995 to 2000 [9] are shown in the following table. Figure 2: Extent of fire spread in Canadian federal prison facilities 1995-2000 Fire Spread Number of

Fires Percent Deaths Injuries

Confined to Object Ignited 173 63% 0 24 Confined to Room (Cell) of Origin 100 36% 1 25 Confined to Floor of Origin 2 1% 0 0

Total 275 100% 1 49



The above statistical data indicates that fires in the Canadian federal prisons were effectively contained within the room of origin, i.e. 99% of the reported fires are confined to either the object ignited or within the fire origin room. The possible reason for the effective control of these fires could be because that all Canadian federal prison living units are fully sprinkler protected. With the provision of the sprinkler system, it effectively prevents significant and life threatening fires from occurring.

4.3 USA

The NFPA publication [10] on fires in Prisons and Jails in the USA indicates that 52% of the fires from 1999 to 2002 were intentionally lit, and 55% of prison and jail fires started in bedrooms or cells. The following table is extracted from the report and presents the sources of heat for these fires. Figure 3: Heat Source 1999-2002 Annual Average

This data indicates the most likely source of fire ignition is due to match, lighter and smoking materials, which suggest most of the fires started either by careless or malicious behaviour. Radiated or conducted heat from operating equipment, arcing



and heat from powered equipment are the next grouping of significant ignition sources. Another finding from the above table is that there were no deaths reported. Like the Canadian data, this may be attributed to the NFPA 101 [11] and NFPA 5000 [12] requirement for sprinklers in new prisons, although the report does not indicate whether some or all of these fires occurred in sprinkler protected prisons. The following table extracted from the NFPA report lists the item first ignited. Figure 4: Item First Ignited 1999-2002 Annual Average

This data indicates that the most likely first ignited material will be the prisoner’s bedding material (30%), which is far higher than any other first ignited item, either electrical wire or cable insulation (7%) or clothing (7%), which supports the earlier



information that 55% of fire occur in the cells. Data on the extent of fire damage, refer extract from NFPA report below, indicates the fires in the USA prisons were effectively contained within the room of origin, i.e. 98% of the reported fires are confined to either the object ignited or within the fire origin room. Figure 5: Extent of fire damage 1999-2002 Annual Average

4.4 UK

Although the UK document “Custodial Property – Fire Safety Design Guide for Custodial Property” [13] does not provide any statistical data, it does provide an insight in the nature of fires in UK facilities. The document indicates that the number of ‘accidental’ fires is considered to be ‘low’ but the number of ‘deliberate’ fires is considered to be high, with an estimate that over 90% of fires in prisons are started deliberately. Similar to what was previously discussed; this document indicates that some of the reasons for these fires are: • Cause disruption as part of a disturbance or incident; • Seek attention; • Cause self-harm; • Retaliate against another person; and • Part of a diversionary tactic

4.5 Review of statistics

The statistical data presented here provides an insight in the fire hazards in prisons, although care has to be used when applying this data to projects in Australia. The data suggests that deliberate fires are common in prisons, and that these tend to be small and lit in the prison cells. The data from the USA and Canada provides insight



into the extent of spread of fires, and that the majority tend to be confined to the room of origin. The data did not indicate whether these were or were not sprinkler protected prisons, but the design requirements for new prisons in these countries require sprinkler protection. The recent Australian data indicates fire fatalities are rare, but, as stated previously, more historical data (1980’s) gave example of two significant fires in Victoria that resulted in fatalities. In the case of Jika Jika, it is understood that the inmates barricaded themselves inside the building. The general conclusions that could be reached from this data, for application to Australian projects, are that: • Most of the prison fires were intentionally lit, and the majority of the deliberate fires

were located in cells. • The most likely first ignited material in a prison fire is the prisoner’s bedding

material. • The majority of the reported prison fires were confined to the object ignited or to

the room of origin. Fire spreading beyond the cell of origin is unlikely. • The number of injuries caused by the prison fires was low, and death is rare. 5 PRISON DESIGN CODES

In Australia prisons are required to comply with the Building Code of Australia. However, the Deemed-to-Satisfy (DtS) provisions of the BCA do not provide specific guidance on the design of prisons and thus a performance based design would be required. In Victoria there is a guideline document [6] to aid in the design of prisons in Victoria, and there was but now withdrawn document in Queensland (Queensland Development Code (QDC) Part 3 – Detention Centres). To aid in the development of a performance based design, to determine suitable trial concept designs for the scenario development, guidance can be taken from other codes that specifically address prison fire safety. Two examples are the NFPA Codes (NFPA 101 and NFPA 5000) and the UK document ‘Fire Safety Design Guide for Custodial Property’

5.1 NFPA 101 & NFPA 5000

Both the Life Safety Code (NFPA 101) and Building Construction and Safety Code (NFPA 5000) provide guidance on construction of new detection facilities. These two



codes are very similar, and the safety requirements are almost identical. The two NFPA Codes recognise that the safety of all occupants in prisons cannot be adequately ensured solely by dependence on evacuation of the building, their protection from fire shall be provided by appropriate arrangement of facilities; adequate, trained staff; and development of operating, security, and maintenance procedures composed of the following: (1) Design, construction, and compartmentation (2) Provision for detection, alarm, and extinguishment (3) Fire prevention; and planning, training, and drilling in programs for the isolation

of fire, transfer of occupants to areas of refuge, evacuation of the building, or protection of occupants in place

(4) Provision of security to the degree necessary for the safety of the public and the occupants of the facility

The prescriptive requirements are impart dictated by the use of the facility and the ability of detainees to evacuate from their sleeping accommodation to safety. The codes define five (5) levels of ‘Use Condition’ ranging from ‘Use Condition I’ where detainees are able to freely move to an exit, to ‘Use Condition V’ where there movement is restricted and all doors in the egress path are controlled by staff. Depending on the various Use Conditions, there are special requirements for the subdivision of the resident housing spaces. A key aspect of the NFPA requirements is that all the new residential housing buildings for the prisons classified as Use Condition II to V are to be protected throughout by an approved, electrically supervised automatic sprinkler system installed in accordance with NFPA13. Condition Use I (where inmates have the ability to move to an exit) is not required to have a sprinkler system.

5.2 Fire Safety Design Guide for Custodial Property in UK

Prisons constructed in the UK under the auspices of the Crown are exempt from procedural control of the Building Regulations. However they are generally designed to comply with the substantive requirements of the Regulations. To aid with the design of prisons to comply with the Building Regulations, the Ministry of Justice has produced a design guide called “Fire Safety Design Guide for Custodial Property” [13]. The Guide indicates that Custodial Property is considering the need for active fire suppression systems in these types of facility. The Guide indicates that BRE were



commissioned to carry out a fire safety survey of prisons and provide recommendations, and a copy of the BRE Executive Summary is provided in the Guide. The BRE indicate from tests carried out that the installation of sprinklers would provide life safety benefits for cell occupants from a fast flaming fire. However BRE question the benefit of sprinklers when considering the risk reduction against the deliberate interference with safety equipment by inmates and the overall cost of the system. The Guide provides some prescriptive requirements, but allow for performance based design. Prescriptive requirements include distance to exits, exit widths, minimum periods of fire resistance and compartmentation sizes, and that cells should form their own fire contained room. Automatic detection and warnings systems must be provided unless the designer can demonstrate that they are not required or are impractical. A fire engineer should be engaged to demonstrate that the smoke hazard management system will maintain tenable conditions in the evacuation routes outside the cells. Hose reels are provided with inundation points in cells doors to allow staff to introduce water into the cells. 6 FIRE SCENARIO SCREENING AND GROUPING

One approach to assessing fire safety in a prison is to undertake a quantitative analysis such as the Available Safe Egress Time (ASET)/Required Safe Egress Time (RSET) comparison. The ASET/REST assessment can be used to determine if the proposed fire safety design will meet the performance requirements of the local code. Therefore, it is important to choose which fire scenarios are to be studied. Johnson et al [1] suggest that three groups of fire scenarios are to be considered: • Design fires • High challenge fires (for sensitivity testing) • Extreme events (scenarios beyond design)

6.1 Design Fire Scenario

The design fire category is an approximation of the reasonable worst-case fire scenario expected over the life of the building. Consideration should be given to the type of furniture, furnishings and textiles to assess the design fire growth rate,



maximum heat release rate, and the fire products that would be produced. The review of statistical data in Section 4 shows that the majority of the reported prison fires were confined to the object ignited. The reason for these confined fires might be because of the early detection system, early intervention by the prison guards, the suppression system, and/or the inmates’ intention for starting the fire. As mentioned in Section 3.3, Carson [4] suggests the main motives for the malicious lit fire is to cause aggravation or irritation. Therefore, it might be appropriate to consider a minor arson fire within the cell for the design fire scenario. The inmate is assumed to start the fire with the intention to catch the prison guards’ attention or to protest against conditions and not for self-harm. In the design fire scenario, it is suggested to assume that all the fire safety systems provided activate as expected, typical fire growth rates as expected from the fuel package available in the studied area are used, and the prison guards attending the fire incident within the expected time limit. In each ASET/RSET assessment, it is important to include a factor of safety in the design. According to the International Fire Engineering Guideline [11], the margin of safety for a particular design fire scenario should be assessed based on a range of variables such as: • Extent of redundancy in the trial design • Method of analysis and modelling assumptions • Variability of the input parameters • Potential consequences of the design fire scenario • Expected return period of the design fire scenario As the design fire scenario makes the optimistic assumptions, a generous margin of safety should be used for the design fire scenario for the ASET/RSET comparison. It is therefore suggested a factor of safety of 2 could be applied to the prison guards’ response time to allow for the unanticipated delay in the evacuation time.

6.2 High Challenge Design Fire Scenario

For this high challenge design fire scenario, a more severe arson fire within the cell is suggested. This might be a deliberately lit fire is because the inmate is attempting self-harm.



With the self-harm intention in mind, the inmate might gather more fuel packages to build a bigger fire with a faster fire growth rate. The designer should make a judgement on the appropriateness of assuming a failure of one fire protection system. The fire is assumed to start in a particularly onerous location for the evacuation. As the high challenge design fire scenario has allowed the onerous assumptions, the margin of safety could be reduced for the ASET/RSET comparison of this high challenge design fire scenario.

6.3 Extreme Fire Scenario

For the extreme fire scenario, it is not suggested to carry out an ASET/RSET assessment. This type of fire scenarios could include multiple ignition sites starting by organised crime, riots in the prison, and the inmates barricade the prison guards’ ability to intervene with the fire, etc. For this type of fire, it is not practicable to design, and it would require many mitigation measures in place to fail before such an extreme fire could occur. The suggested ways to approach the extreme fire scenario are to mitigate it from happening, control the likely fire spread area, and have procedure in place to deal with this rare event. Some feasible options in addition to the normal passive and active fire safety measures might be: • Limit/restrict the ignition sources – such as prohibit smoking in the cells • Use fire retardant furniture in the cells • Limit/restrict the fuel load in the cells • Use robust fire rated construction to contain the fire within the incident origin • High level of surveillance to interfere with the inmate’s unusual behaviour

7 CELL BLOCK FIRE DESIGN EXAMPLE

To illustrate the how the above suggested processes as indicated in Figure 1 flowchart could be used in the cell block fire scenario, the following example is used. The building occupant and fire characteristics analysis might be based upon a cell



block accommodating high security classification inmates under a high level of surveillance. The inmates’ movement is restricted to be within the cell block during the day time and they will be locked in their cells during the “locked down” periods. Each cell only accommodates up to two inmates and both beds are fixed to the ground, i.e. not bunk beds that can be placed one above the other. For the hazard/risk analysis, the following conditions are used in this example: To consider the general layout, the inmates have restriction in their movement and they would need the prison guards to assist them with egress. In this high security classification cell block, the inmates are prohibited from smoking, which reduces the inmates’ access to the ignition source. The prison management has the policy to empty the rubbish bin every day in the cell block area, and no rubbish bins are provided within the cell. This management procedure reduces the fuel sources in the cell block. The high security classification cell block also has a very strict allowance on the amount of personal belongings that inmates are permitted to have within their cell. They are provided with fire retardant mattress/bedding/pillows and non-combustible furniture (e.g. tables and chairs) in the cell block. As concluded in Section 4.5, the most likely first ignited material is the prisoner’s bedding material, and the fire is most likely to be confined to the object first ignited. With all the above information, consideration is given to the possible fire scenarios, they might include: • a fire involving the fire retardant mattress (30% of the prison fires starts from this

source) • a fire involving clothing (7% of the prison fires starts from this source); and • a fire involving paper (6% of the prison fires starts from this source); Data may be available to help quantify the size and character of the design fires. As an example, fire tests may have been done on the type of mattress/beddings to be used in the facility. In a recent project, a fire test report has shown that a fire retardant mattress has a slower than slow “t2” fire growth rate with the peak heat release rate of around 130kW and a burning duration greater than 15 minutes.



Lawson [15] has carried out a fire test on a metal wardrobe with clothes as the fire load. In the fire test, these clothes were placed into a wardrobe on 16 clothes hangers which were evenly distributed across the wardrobes. The result from the test showed that the hanging clothes fire has a fire growth rate between “medium” and “fast” t2 fire, and the peak heat release rate from a fire load of 16 clothes (total mass of 1.93kg) is about 270kW. However, once the fire reaches its maximum heat release rate, it starts to decay, and the burning was not sustained for a long duration (less than 5 minutes). It should also be noted that with in prison cells, it is unlikely cloth hangers will be provided as they could be a self-harm source; it is less likely for the clothes to be hung up to encourage vertical fire growth. Therefore, the cloth fire is expected to have a slower fire growth rate than the tested results. Initial Fire [16] has shown that for a 14L polyethylene waste basket with net walls (mass of 0.53kg) filled with 0.2kg shredded paper, the maximum heat release rate is approximately 20kW. Then the fire growth rate starts to decay and remains steady at a heat release rate of approximately 4kW. The results from the above tests showed that the waste paper basket has a fire growth rate between “medium” and “fast” t2 fire. The fire burns itself out in approximately 5 minutes. From the above information, a design fire scenario that could be chosen is a mattress fire with a “medium” t2 fire growth rate with a peak of around 260kW (the peak heat release rate of two mattresses) for the cell with two inmates. The reasons for this decision are: • The mattress/bedding fire represents the majority of the prison fire • The mattress/bedding used in the cell is fire retardant; therefore, the inmate might

have to use some paper or a piece of cloth to start the mattress fire. For this reason, the fire growth rate chosen is to be medium growth rate.

As discussed in Section 6.2, the high challenge fire scenario considers the scenario when the inmate starts the fire with the intention to injure oneself. For this scenario, the inmate might use readily accessible fuel packages to build a bigger fire with a faster fire growth rate. From the above information, the high challenge design fire scenario might be a fire with a fast fire growth rate with a peak of 400kW which is approximately 50% greater than the peak heat release rate of the design fire scenario for the cell with two inmates. It should be noted that each prison is unique as to the permitted fire load in the cell,



management procedure, smoking policy, etc. therefore the design fire and the high challenge design fire scenarios shall be considered separately and there is no one fire that would fit all situation. The flowchart in Figure 1 provides a good guideline as how to formulate the appropriate design fire scenarios. 8 CONCLUSION

The methodology suggested by Johnson et al [1] for determining design fires for ‘design’, ‘high challenge’ and ‘extreme events’ scenarios requires a thorough understanding of the building and its use, occupant characteristics, fires hazards and trial concept. This paper has summarised some of the key issues associated with the operation of a prison that will impact on the development of a trial concept design, in particular the conflict of security requirements against fire safety requirements, the nature of the inmates with their malicious and self-harm behaviour, and the high number of fire deliberately lit. As guidance in the BCA is limited for developing a trail concept design for prisons, guidance can be obtained for other codes and guidelines, although these may differ in their approach. The NFPA codes (NFPA 101 and NFPA 5000) require automatic sprinklers in prisons where inmates cannot evacuate to an exit, whilst the UK guidance document is reviewing the requirement for sprinklers but does require smoke hazard management systems to maintain tenable conditions in the egress paths. It would appear from the statistical data that fires in prisons are quite common, but are relatively small and extinguished by staff, and although there is a high number of fire starts fatalities appear to be rare. However, fire fatalities have occurred, and these might be as a result of more extreme circumstances. 9 REFERENCES

1. Johnson, P.F., Boverman, D., Johnson, C.E., 2008, “Scenario Analysis in Fire Engineering of Major Projects” at The International Bushfire Research Conference 2008, The Adelaide Convention Centre, Australia, 1 September 2008.

2. Australian Building Codes Board, “Building Code of Australia 2008”, Canberra, Australia, 2008.

3. “Investigations of the Fire in the Detention Centre at Schiphol-East, 26 October



2005”, Interflam 2007. (Interflam '07). International Interflam Conference, 11th Proceedings. September 3-5, 2007, London, England, 1193-1204 pp, 2007. P.H.E. vande Leur, F.P.H. Jakobs, M. Haas, M. Klein

4. Carson, W.G., “Detention and Correctional Facilities”, Section 9 Chapter 7, NFPA Fire Protection Handbook, 18th ed., National Fire Protection Association, Quincy, MA, USA, 1997

5. Dear, G., “Preventing Self-Harm in Prison: Do We Need Different Strategies for Indigenous and Non-Indigenous Prisoners?”, School of Psychology, Edith Cowan University, WA, 1999

6. Department of Justice, “Cell & Fire safety Guidelines for Victoria”; Corrections Victoria, Australia, 2003.

7. Statistical Data, Fires in NSW DCS 2002-2007, Private Correspondence provided by NSW Department of Corrective Services, NSW, Australia, 2008

8. Statistical Data, Fires in QLD DCS 2005-2006, Private Correspondence provided by QLD Department of Corrective Services, QLD, Australia, 2008

9. Su J., Gaw R., Richardson K., Taber B. and Carpenter D., “Smoke Detectors in Prison Cells”, Fire Protection Engineering, October 1, 2006

10. Ahrens, M. , “Selections from U.S. Fires in Selected Occupancies – Prisons and Jails”, National Fire Protection Association, Quincy, MA, 2006

11. NFPA 101, Life Safety Code, National Fire Protection Associate, Quincy, MA, 2009

12. NFPA 5000, Building Construction and Safety Code, National Fire Protection Associate, Quincy, MA, 2009

13. Custodial Property, “Custodial Property – Fire Safety Design Guide for Custodial Property”, London, UK, 2008

14. Australian Building Codes Board, "International Fire Engineering Guidelines”, Edition 2005, Canberra, Australia, 2005.

15. Lawson, J.R et al, “Fire Performance of Furnishings As Measured in the NBS - Furniture Calorimeter. Part I”, National Bureau of Standards, NBSIR 83-2787, U.S.A. 1983

16. Sardqvist, S, “Initial Fires”, Lund, ISSN 1102-8246, Lund University Institute of Technology Department of Fire Safety Engineering, 1993

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