HIGH RISE FORUM SUMMARY PAPER - Fire & Rescue NSW · HIGH RISE FORUM SUMMARY PAPER PAPER PREPARED...

NSW FIRE BRIGADES

HIGH RISE FORUM SUMMARY PAPER

PAPER PREPARED BY;

STATION OFFICER

Mark Porter

STRUCTURAL FIRE SAFETY UNIT

November 2009

NSWFB High Rise Forum 2009 – Summary Document

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1 Executive Summary This paper outlines the major outcomes and issues raised at the two NSW Fire Brigades (NSWFB) High Rise Forums held at the NSWFB Greenacre complex on Wednesday 4th & 11th November 2009. This paper details the following;

• A brief overview of the forums held;

• A brief overview of the capabilities of some NSWFB appliances, fire fighting techniques and their implications for industry and AS2419.1 – 20XX;

• The concerns of industry representatives regarding some of the current provisions of AS2419.1 – 2005. In particular the issues associated with the location requirements and provision for hydrant booster assemblies, fire brigade relay pumps and the use of ‘Insert Type Single Point Boosters’ in fabricated booster assemblies;

• The concerns of the NSWFB regarding the application of some of the design parameters of AS2419.1 [i.e. a design complying with AS2419.1 – 2005 currently allows for attack hydrants to be provided with an unassisted pressure of between 250 and 350 kPa (state or territory dependent). Consequently where a roof top tank is installed; unassisted pressures which meet the prescriptive provisions of AS2419.1 can be obtained 25 metres or more below the level of the tank without the use of pumps. These pressures however in some instances do not meet the needs of attending fire brigades particularly, in regards to high rise incidents.

• Some simplistic schematic drawings of the concept designs developed by forum attendees and associated commentary on these designs;

WARNING: All drawings presented in this document are at best a simple schematic representation of the concept being depicted and as such cannot be considered as the basis for design. Further to this, none of the concept designs developed in collaboration with other forum attendees and presented in this document meets the requirements of AS2419.1 – 2005. It should also be noted that apart from the information relating to the capabilities of the NSW Fire Brigades (e.g. the capability of NSWFB appliances), the concepts and ideas detailed in this document do not have support from regulatory authorities, the NSWFB or interstate or territory fire services; but instead represent a summary of the dialogue that occurred over the two (2) days of the high rise forum.


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1 Executive Summary...............................................................................................2

2 Introduction............................................................................................................4

3 NSWFB Overview.................................................................................................5

3.1 Appliance Capabilities ...................................................................................5

3.2 Fire Fighting Techniques ...............................................................................6

3.3 Fire Fighting Hose .........................................................................................7

4 Design Implications ...............................................................................................7

4.1 General...........................................................................................................7

4.2 Fire Fighting Techniques ...............................................................................7

4.3 Fire Appliances ..............................................................................................8

5 AS2419.1 – 2005: A compliant design? ................................................................9

6 Hydrant Booster Assemblies................................................................................10

6.1 General.........................................................................................................10

6.2 ‘Single insert type booster points’ ...............................................................11

6.3 Commissioning of hydrant booster assemblies............................................13

6.4 The location of hydrant booster assemblies.................................................13

6.5 Comments ....................................................................................................16

7 Relay pumps / Pressure Reduction ......................................................................17

7.1 General.........................................................................................................17

7.2 Multi-outlet pumpsets ..................................................................................18

7.3 Control of on-site pumpsets .........................................................................19

7.4 Pressure Reduction.......................................................................................19

8 Alternative Designs..............................................................................................19

9 Conclusion and implications for AS2419.1 – 20XX ...........................................22

10 High Rise Forum No 1 – Attendees.................................................................23

11 High Rise Forum No 2 – Attendees.................................................................24

12 High Rise Forum Feedback .............................................................................25


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2 Introduction In response to a variety of high rise designs submitted to the NSWFB during the early part of 2009, the NSWFB committed to the undertaking of a number of ‘High Rise Forums’. The aim of these forums was to promote discussion amongst representatives from industry, regulatory authorities and interstate and territory fire brigades about the issues associated with hydrant systems serving multistorey buildings. Consequently over the course of two days some 54 people had the opportunity to air their concerns and propose alternatives to the current provisions of AS2419.1-2005. A similar format was followed for each of the two forums held (i.e. on the 4th & 11th November). For the second forum though participants were provided with a summary of the issues raised and concept designs developed in the first forum. Detailed below is the agenda that was loosely followed for each day of the forum (i.e. the direction of forum was to some degree dependent on the discussion being undertaken within the group on the day).

Agenda Item Speaker

Opening Forum No1. Chief Superintendent Greg Buckley

Forum No2. Assistant Commissioner Jim Smith

Topic 1 – Hydrant booster locations Open Forum

NSWFB Standard Operational Guidelines High Rise Fires

Presenter / guest speaker

NSWFB Pump Performance Presenter / guest speaker

Multistage Pumpsets Presenter / guest speaker

Topic 2 – Fire Brigade Relay Pumps Open Forum

Topic 3 – Pressure Management Open Forum

Reticulated Water Supplies Presenter / guest speaker

Topic 4 – Water Supplies Open Forum

Topic 5 – Other Open Forum

FEEDBACK – In an attempt to determine participants thoughts on the high rise forums held (i.e. was it a worthwhile exercise or not) a pro-forma feedback sheet is provided at the end of this document. It is hoped that all participants of the forum will take the time to complete this pro-forma document and forward it to one of the following addresses;

• Email: [email protected] .au; or

• Post: Attention Mark Porter C/O NSW Fire Brigades Locked Bag 12, Amarina Avenue GREENACRE 2190


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3 NSWFB Overview

3.1 Appliance Capabilities The NSWFB currently (i.e. in 2009) have two standard type pumpers in their fleet these being the Class 2 and Class 3 Urban pumpers. It should be noted that the NSWFB have other urban pumpers which provide an equivalent performance to the Rosenbauer Pumps discussed below. The Class 2 Urban Pumper is fitted with a 2000 litre water tank and a Rosenbauer NH30 pump. The Rosenbauer NH30 is a multi-pressure pump with a single-stage gearbox driven by the appliance’s engine via a split-shaft PTO. The pump is a multi pressure type (high and normal pressure) capable of flows up to 3000 litres per minute. The Class 3 Urban Pumper is fitted with an 1800 litre water tank and a Rosenbauer NH40 pump. The Rosenbauer NH40 is a multi-pressure pump with a single-stage gearbox driven by the appliance’s engine via a PTO. The pump is a multi pressure type (high and normal pressure) which has been internally geared for a pump flow rate of 3500 L/min. Figure 1 below details the pump curve for the Rosenbauer NH40 pump. The dotted line has been added to highlight the capability of the pump. In this instance when delivering 1600 litres at 1400 kPa the pump’s power consumption is approaching 100% (i.e. the pump is approaching its maximum performance at this pressure).

Figure 1


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These pumps also allow the NSWFB appliances to draft water from static / open water supplies. Figure 2 below details the maximum static lift these pumps can achieve without loss of performance (i.e. 3 metres). At depths below this level a progressive loss of pump performance occurs until the theoretical maximum of 9.8 metres is reached where no lift is possible.

Figure 2

3.2 Fire Fighting Techniques

NSWFB firefighters, indeed all fire fighters throughout Australia, when involved in structural fire fighting and depending on the circumstance (i.e. size of fire) will initially employ ‘gas cooling’ techniques (i.e. cooling of the hot gas layer) that involves applying short pulses of water under high pressure (i.e. 700 kPa) into the hot layer. However once the area of fire origin has been reached firefighters will typically alter their approach (i.e. no longer apply the ‘gas cooling technique’) and employ higher flows to extinguish the fire. In the control of a hostile fire environment firefighters upon making entry into the fire compartment will direct these short pulses into the hot gas layer immediately above or directly in front of them. The application of these short pulses from hand held hose streams allows fire fighters too;


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• control and manage the surrounding environment; and

• extinguish the fire in the most effective manner

3.3 Fire Fighting Hose The NSWFB fire appliances typically carries Class M lay flat non-percolating fire hose designed in accordance with AS2792 on all its urban pumpers. Table 1.1 of AS2792 is reproduced below.

CLASSIFICATION OF FIRE HOSE

Class Working Pressure

kPa

Proof Test Pressure

kPa

Burst Pressure

kPa

L (Low) 1000 1500 2500

M (Medium) 1400* 2100 3500

H (High) 2100 3150 5250

Table 1 * Emphasis added to highlight the fact that the standard fire fighting hose carried by all NSWFB appliances has a rated working pressure of 1400 kPa (i.e. when delivering water typically the limiting factor for fire brigades is the lay flat hose used).

4 Design Implications

4.1 General The performance and capabilities of fire appliances, the fire fighting techniques employed (i.e. ‘gas cooling’) and the fire fighting hose used by fire brigades all have significant implication for designers of fire hydrant systems. Indeed it could be strongly argued that it is not possible to design a fire hydrant system that meets the needs of the attending fire brigade without a comprehensive knowledge of these factors. The implications for hydrant design are discussed below.

4.2 Fire Fighting Techniques The introduction of ‘gas cooling’ techniques by Fire Services across Australia was the precursor for change in AS2419.1-2005 (i.e. from 2005 onwards when a pumpset was installed it was required to provide 700 kPa at the most disadvantaged fire hydrant therefore allowing firefighters to apply ‘gas cooling’ techniques immediately if the fire scenario warranted this approach). The provision of 700 kPa at the hydrant outlet provides firefighters with the pressure to create water droplets of approximately 0.3mm at the fire fighting branch nozzle which optimises the cooling effect of the water delivered into the hot gas layer and therefore mitigates the possibility of producing ‘wet steam’ (i.e. at lower pressures droplet size increases therefore either reducing the effectiveness of the ‘gas cooling’ technique or prohibiting its application altogether). With consideration to the information detailed above when designing a fire hydrant system, designers should always be considerate of the range of pressures firefighters


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may require to extinguish a fire in a given occupancy. Where an on-site pumpset/s is required to be installed it should serve all hydrants in the design (i.e. 700kPa should be provided to all hydrant outlets). For a high rise building, on levels where this pressure can be achieved by head pressure from a roof top or elevated tank, the installed pumpset/s need not serve these floors (i.e. 700 kPa is provided from static head alone).

4.3 Fire Appliances For a hydrant designer an understanding of the capability of the attending fire brigades’ fire appliance has significant implications for any design developed. It is recommended that in all instances hydrant designers ask the following questions;

1. ‘To what level or storey can the attending fire brigade appliance provide 700 kPa to the fire floor’; and

2. ‘To what depth can the attending fire brigade appliance draft water (i.e. what is the vertical lift capacity of the attending fire brigade)

In relation to point (1) above the significance of the installation of Rosenbauer NH30 and NH40 pumps to NSWFB urban pump fleet is illustrated in Figure 3 below, which looks at the capability of these pumps to deliver water to the fire floor in a high rise situation (i.e. at the highlighted point in pump curve detailed on page 5 the maximum height at which a NSWFB urban pumper can provide 700 kPa on the fire floor is 35 metres in effective height). It should also be noted in this example that at 1400 kPa the lay flat fire hose used is at its maximum working pressure as detailed in AS2792.


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Figure 3 In relation to point (2) above the capability of the Rosenbauer NH30 and NH40 to draft water (i.e. maximum 3 metre lift with no loss of performance) have significant implications for hydrant designers seeking to locate a tank below ground. In all instances where a tank is proposed to be installed below ground [i.e. three (3) metres to the lowest part of the tank] the NSWFB or other fire authority having jurisdiction should be consulted to avoid costly design changes and to ensure that the design developed meets the operational needs of the attending fire brigades.

5 AS2419.1 – 2005: A compliant design? As a starting point and to promote discussion amongst high rise forum participants the high rise design detailed in Figure 4 below was presented at each forum. Under the provisions of AS2419.1 in some circumstances internal attack fire hydrants are permitted to have unassisted pressures of 250 (NSW only) and 350 kPa (all other states and territories). In relation to this matter hydraulic designers need to understand that this is a compromised position between industry and fire brigades to limit the installation of on-site pumpsets for low rise buildings and therefore should not be considered as a comment on the pressures needed by firefighters to effectively undertake internal fire fighting operations (i.e. for internal hydrants fire firefighters would like 700 kPa to be available in all instances).


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Figure 4 Figure 4 above then details a hydrant design that provides ‘unassisted’ pressures to the second highest pressure zone and below from the roof top tank. Does this design meet the operational needs of fire fighters responding to a call of fire on the storey located 195 metres above ground in this building? Most definitely not it was indicated to forum participants. A compliant design? In relation to this matter it is the NSWFB opinion that Note 2 to Table 2.2 of AS2419.1 – 2005 specifies that once pumps are incorporated that attack hydrant pressures and flows must be attained in accordance with Table 2.3.

6 Hydrant Booster Assemblies

6.1 General In relation to hydrant booster assemblies and their requirements under the provisions of AS2419 Parts 1, 2 and 3, three main issues were raised. These are as follows;

1. The problems associated with the use of ‘Single Insert Type Booster Points’ in fabricated hydrant booster assemblies; and

2. The lack of commissioning or inappropriate commissioning of fire hydrant systems (i.e. from the forum the issue of the NSWFB becoming involved in the commissioning of hydrant systems was raised by forum participants); and


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3. The problems associated with the protection requirements for hydrant booster assemblies, particularly in relation to premises with small frontages (i.e. the prescriptive provisions of Clause 7.3 Location of AS2419.1 present many problems for hydrant designers and architects alike)

6.2 ‘Single insert type booster points’ At the first of the high rise forums one of the attendees indicated that the current non conformance of single insert type booster assemblies with AS2419.3 and their incorrect installation is a significant issue for fire fighters (i.e. possibly compromises their safety) and hydrant designers (i.e. possible legal implications for those practitioners signing off on these designs). The series of photos and drawings below attempt to explain the issues associated with ‘Single Insert Type Booster Points’.

Figure 5

Insert Type Single Point Booster’ with Storz fitting attached and secured in a length of DN80 galvanised pipe by a rolled groove coupling

Figure 6

Insert Type Single Point Booster’ with Storz fitting attached removed from the length of 80DN galvanised pipe.

The photo is intended to highlight the problem of the manifold being to long for the valve of the ‘Insert Type Single Booster Point’.

The implication of this installation method (i.e. manifold pipe too long) is that nil or a significantly reduced flow is provided to the rising manifold pipe of the fabricated hydrant booster assembly.

Figures 7 and 8 below attempts to diagrammatically represent this water flow through a hydrant booster assembly inlet. In Figure 7 the ‘Insert Type Single Point Booster’ allows for full flow as the valve of the insert type single point booster is able to extend fully into the rising manifold of the hydrant booster assembly. Conversely; in Figure 8 full flow is not able to be achieved through the hydrant booster inlet due to the manifold pipe being too long.


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Figure 7

Figure 8 In relation to the issues associated with ‘Insert Type Single Point Boosters’, forum attendees’ ideas and suggestions ranged from the requirement that AS2419 parts 1, 2 and 3 should indicate that all components / products used in a fire hydrant system are


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to be listed; to that of the NSWFB becoming involved in the commissioning of fire hydrant systems. Note: The NSWFB is currently formulating a Guideline for the use of ‘Insert Type Single Point Boosters’ and their use in hydrant booster assemblies.

6.3 Commissioning of hydrant booster assemblies With the problems associated with ‘Insert Type Single Point Boosters’ and hydrant systems in general the question of the NSWFB becoming involved in the commissioning of fire hydrant systems was raised. It was subsequently indicated that this issue has been discussed within the Structural Fire Safety Unit and it is indeed an option to be explored however issues such as resource availability and possible industrial matters would have to be addressed before the NSWFB could become involved in commissioning of fire hydrant systems. It should be noted that on the 12th November 2009 at the NSWFB complex at Greenacre a meeting was held amongst those fire brigade representatives who attended the second high rise forum; in this meeting the commissioning of hydrant systems was discussed. In the course of the discussion it became clear that those fire brigades that were currently actively involved in the commissioning of fire hydrant systems had fewer issues than those currently seen in NSW.

6.4 The location of hydrant booster assemblies The protection requirements of Clause 7.3 were raised by forum attendees as a major issue confronting designers and architects alike. In an attempt to promote a balanced discussion of this issue forum attendees were asked firstly to indicate what are the positives associated with the current requirements of Clause 7.3 Location of AS2419.1-2005, the following thoughts were offered; the requirements ensured that it is readily accessible, easily seen and identifiable to responding fire brigades. In support of these benefits the NSWFB made reference to the fire growth curves typically applied by fire engineers (see figure 7 below) to highlight the importance of being able to readily identify and locate the hydrant booster assembly and for that matter any fire hydrant in general.


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'T' Squared Fires

0 120 240 360 480600

720840

9601080

1200

0

50000

100000

150000

200000

250000

300000

0 120 240 360 480 600 720 840 960 1080 1200

Time in seconds

Hea

t Rel

ease

Rat

e (k

W)

Ultrafast fires

Fast fires

Medium fires

Slow fires

Figure 9 The significance of these fire growth rates is that for a non-sprinkler controlled fire; the fire will continue to grow until the fire brigades have commenced fire fighting operations (i.e. the longer the responding fire brigades take to locate and get the hydrant booster assembly to work the larger the fire they will be required to confront and extinguish). Table 2 below looks at the implications for firefighters of a fast growing fire.

Time (sec)

HRR (kW)

Comment

600 16880 After 10 minutes (i.e. typical arrival time for a fire appliance in the metropolitan area of Sydney) the fire has a heat release rate of 16880 kW.

720 24307.2 Two (2)minutes later the fire has increased in size by approximately 50%

840 33084.8 Four (4) minutes later the fire has effectively doubled in size (i.e. if takes fire fighters four minutes to get the hydrant booster assembly to work and commence fire fighting they now have to extinguish a fire that is double its original size)

960 43212.8 Six (6) minutes later the fire is now 2.5 times larger than it was upon arrival of the fire brigades

Table 2 On the negative; forum attendees listed three (3) main concerns regarding the location requirements for hydrant booster assemblies. These being;

(i) the requirement to provide the 90/90/90 surround for sprinkler protected buildings (i.e. in view of the benefits provided by sprinklers industry indicated that the provision of 90/90/90 surround was particularly onerous); and


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(ii) the requirement to provide the 90/90/90 surround for buildings with small street frontages was particularly onerous [i.e. with the inclusion of back flow prevention the required surround can reach up to six (6) metres in length]; and

(iii) the requirement to allow only ten (10) litres per second for each boost inlet was considered to be a restrictive (i.e. a forum attendee indicated that more than 10 litres a second could be flowed through the hydrant booster assembly inlets)

In relation to point (ii) above a forum representative from an authority having jurisdiction (AHJ) indicated that where possible they would like to see as much natural light as possible entering the ground floor of premises (i.e. the protection requirements for hydrant booster assemblies in some instances greatly reduce the amount of natural light entering the ground floor of some occupancies). In relation to point (iii) above no disagreement was voiced from high rise forum participants regarding this statement. Another issue raised, relating to the location of hydrant booster assemblies, was that AS2419.1 needed to define the location of the primary vehicle entry point. With consideration of the pros and cons raised by forum attendees regarding Clause 7.3; each forum group was asked to come up with suitable alternatives. The suggestions and comments provided are summarised below;

(i) Concessions should be provided for sprinkler protected buildings (i.e. the FRL requirements of Clause 7.3 should be negated for sprinkler protected buildings). In relation to this matter FRL of _/_/_ to _/120/120 were suggested to supplement the protection already provided by the sprinkler system; or

(ii) Where permanently located raised feed hydrants are provided (or could be provided) within some acceptable distance of the fire brigade booster inlet (i.e. pillar hydrants in a footpath capable of providing the required pressures and flows, similar to the provisions of Ordinance 70), feed hydrants are not required at the hydrant booster assembly; or

(iii) The provision of drenchers alone should not be considered as an appropriate form of protection in non sprinklered buildings. In relation to this matter those who spoke against this suggested form of protection indicated that if a fire were rapidly spreading and growing in a non-sprinklered building the ability of the drenchers alone to protect the hydrant booster assembly was questionable. Conversely in a fully sprinkler protected building the requirement to provide drenchers in fire engineering designs for example was considered to be of limited benefit and an unwarranted cost.

Note: In relation to point (iii) it is the NSWFB understanding that wall wetting systems are available that provide a two hour equivalency for fire separation. In order to provide balance to this document and the suggestions raised above (i.e. concessions should be made available to sprinkler protected buildings) detailed below is the expected heat release rates fire-fighters would be exposed to when attending a sprinkler controlled fire.


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For the purpose of this exercise the building was assumed to have a ceiling height of 3.5 metres and standard sprinklers were installed. Sprinklers with RTI’s of 100, 150 and 200 were modelled using the program FPETool. The fire was assumed to be controlled with the operation of one (1) sprinkler head (Please note this is not the least conservative approach). The fire was assumed to grow at a fast growth rate.

RTI Sprinkler activation

time (Seconds)

Heat Release

Rate (kW)

Comment

100 162 1230.5

If the fire were controlled at this point the heat release rate produced (i.e. 1230.5 kW) is approximately 13.7 times less than that which fire fighters would be exposed to if attending the non sprinkler controlled fire detailed in Table 2 above (i.e. upon arrival a heat release rate of 16880 kW is experienced).

150 181 1536.0

As above, however heat release rate is approximately 10.9 times less.

200 198 1838.0 As above, however heat release rate is approximately 9.2 times less.

Table 3

6.5 Comments In light of concerns raised by industry regarding the requirements of Clause 7.3 Location the following comments are offered;

Idea Comment

(i) Concessions for sprinkler protected buildings

Intend to raise the idea with representatives of other fire agencies to determine if there is support for this suggestion.

(ii) Small street frontages If concessions for sprinklers supported issue may be resolved. If concessions for sprinklers not supported, further suggestions appreciated.

(iii) Provision of fixed pillar hydrants in lieu of valve controlled outlets at hydrant booster assembly

Idea will be explored but in view of comments from AHJ representatives at high rise forum unlikely to be developed


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Idea Comment

(iv) Provision of wall wetting sprinklers only as a means of protection for the hydrant booster assembly in non sprinkler protected buildings

In view of the comments raised at the high rise forum and the NSWFB current understanding of the capabilities of wall wetting systems, further research will be undertaken to determine the suitability of these systems as an alternative means of protection to the hydrant booster assembly.

(v) Increase in the current 10 l/s flow requirement through the hydrant booster inlet

Intend to raise the idea with representatives of other fire agencies but unlikely to be supported at this time in view of the issues associated with ‘Insert Type Single Point Boosters’ and their potential to greatly limit available flow if installed incorrectly

Table 4

7 Relay pumps / Pressure Reduction

7.1 General Using the compliant design detailed in Figure 4 above (i.e. 25,000 litre tank on the roof, relay pump every 50 metres, etc) as a basis for discussion; Table 5 attempts to detail the questions asked by the forum presenter and the responses received from high rise forum participants. Please note: Notes to Table 5 below are post high rise forum comments added to clarify view currently held by the NSWFB.

Questions to ‘Forum’ Participants Responses from ‘Forum’ participants

(i) ‘Under the provisions of AS2419.1-2005 a 25,000 litre tank is required to be provided at the roof of this building?’

‘Correct’

(ii) ‘Under the provisions of AS2419.1-2005 two pumpsets are required to service this tank?’

‘Correct’

(iii) ‘Two pumpsets are required because?’

‘The provision of two pumps allows for appropriate servicing and maintenance to be undertaken’

(iv) ‘Under the provisions of AS2419.1-2005 a relay pump is required to service each pressure zone?’

‘Correct’


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Questions to ‘Forum’ Participants Responses from ‘Forum’ participants

(v) ‘In the design proposed if a relay pump were to fail could the system continue to operate’

‘No.’

Note: In relation this matter it is the NSWFB understanding that the system offers some level of redundancy albeit significantly reduced. For example:

• If all tank water is not consumed prior to hydrant booster operation then NSWFB could revert back to primary pump system (i.e. on site pumps were turned off at the commencement of boosting therefore leaving some water in the onsite tank).

• If a relay pump fails then a reduced Net Positive Suction Head (NPSH) may be provided to the next relay pump and some degree of pressurised fire fighting water may be provided to the fire floor.

(vi) ‘In the design proposed are the relay pumps more reliable than the pumpsets that serve the roof top tank?’

‘No’

(vii) ‘With consideration to the information detailed above (i.e. relay pumps are no more reliable than other pumps utilised in the system), all would be in agreeance that additional redundancy should be provided to the relay pumps (i.e. two relay pumps are required every 50 metres)’

‘NO*’

Note: Emphasis (*) not added (i.e. The participants of the high rise forum indicated that this would be an onerous provision and that alternatives were available to provide redundancy to relay pumps. See Section 8 Alternative Design.

Table 5 Note: In relation to point (vii) of Table 5 it is the NSWFB opinion that a level of redundancy should be provided to the relay pumps; particularly when one considers that in Figure 4 two (2) pumpsets are required to be provided for the on-site supply (i.e. the tank) yet this source of water contributes approximately 24 minutes to the overall water supply (i.e. the required 4 hour supply).

7.2 Multi-outlet pumpsets During each of the high rise forums information was provided from a pump manufacturer regarding the capabilities and performance of multi-outlet pumps (i.e. it was indicated that these pumps had the capability of providing fire fighting pressures to buildings up to 700 metres in height). It was subsequently suggested that these pumps had the capability to overcome current problems with relay pumps (i.e. the


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redundancy issue) and to simplify hydrant design. See Section 8 Alternative Designs for an exploration of this suggestion.

7.3 Control of on-site pumpsets In the discussion on relay pumpsets and multi-outlet pumpsets the issue of the remote control of these pumpsets was raised (i.e. additional to the pumpset control panel and remote from the pump room). It was subsequently indicated that in all instances control should be provided directly to the pumpset [i.e. the Control & Indicating Equipment (CIE) should provide for Run / Stop / Start] and that indirect control through items such as the Fire Indicator Panel (FIP) should be avoided as these add to the complexity of design.

7.4 Pressure Reduction As a by-product of the discussion on relay pumps the issue of pressure reduction was discussed. In relation to this matter a pressure reducing landing valve was presented to the forum. In the discussion that followed some significant concerns were raised about the number of moving parts in the landing valve and their requirement for maintenance as valid reasons why they should not be utilised as a means of reducing pressure in a high rise building. No real opposition was raised against these arguments. Concerns were also raised about the componentry used in pressure management stations to reduce pressure. Of primary concern was the level of servicing this componentry receives. Please note: pressure reduction is further explored in Section 8 ‘Alternative Designs’

8 Alternative Designs In response to the issues raised regarding relay pumps, pressure management and the design of high rise buildings in general a number of hydrant designs were proposed to address these issues. See Figure 8 below for one example.


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Figure 10 Table 6 below; details the primary features of the alternative design and a summary of the commentary on this design. Please note: Notes to Table 6 below are post high rise forum comments added to clarify view currently held by the NSWFB.

Features Comment

(i) Two multi-outlet pumps are provided to serve all pressure zones of the building

The use of two multi-outlets pumps allows for pumps to be serviced and maintained and provides for redundancy in design. Note: It is the NSWFB opinion that redundancy should always be available at an incident. Consequently in certain circumstances the NSWFB would consider that two on-site pumps do not provide an appropriate level of redundancy. For example; at a fire incident where only one pumpset is available due to the secondary pump being inoperative (i.e. due to service or maintenance requirements, awaiting critical spares, etc).


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Features Comment

(ii) The multi-outlets pumps are provided with two independent water supplies (i.e. dual water supplies are provided). These supplies could be either two town mains or a town main and a tank. Size of the tank was left open for discussion (i.e. 1 hour, 2 hours, etc).

The provision of two independent water supplies adds a level of redundancy not currently provided by AS2419.1. Note: It is the NSWFB opinion that in an interconnected town main system unless continuous supply can be guaranteed and maintained (i.e. no manual switching required by the water authority) true independence of supply is not achieved.

(iii) The multi-outlet pumps were proposed to be full flow (i.e. a minimum of 10 L/s for each fire hydrant required to flow)

Full flow provisions are immediately available to fire fighters (i.e. there is no requirement to get the hydrant booster to work). Note: In relation to comment potential OH&S issues would need to be researched further by fire services.

(iv) No hydrant booster assembly is provided to serve the building

It was argued that with the multi-outlet pumpsets providing a similar level of performance to a fire brigade appliance there was no requirement for a hydrant booster assembly to be installed. Note: NSWFB are of the opinion that to provide an equivalent level of redundancy a hydrant booster assembly would be required to be provided to the proposed alternative design.

(v) The provision of dual water supplies and two multi-outlet pumpsets provides for four levels of redundancy.

Proposed design provides an equivalent or greater level of redundancy than current provisions of AS2419 design (i.e. dual water supplies in excess of those currently required under AS2419.1-2005)

Table 6 Variations to the design included above were also offered by forum participants. These being;

(i) The suggestion that multi-outlet pumps deliver water to the top of the building upon which it is delivered throughout the building using a cascade design that utilises pressure reduction stations;

(ii) The suggestion that a hydrant booster assembly be incorporated into the design to provide water either to the on-site tank or directly to the multi-outlet pumpsets (i.e. the hydrant booster assembly primary purpose is to provide additional water to the site if required)

Concerns regarding these proposed alternative designs primarily focussed on the issue of pressure (i.e. if this design were applied hydrant systems could potentially be subjected to extremely high pressures). To mitigate this risk (i.e. excessively high


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pressures within the system) it was suggested that pressures could be managed in the building through the use of break tanks as the design is easily repeated.

9 Conclusion and implications for AS2419.1 – 20XX With consideration to the concerns raised, suggestions proposed and discussions held during the high rise forums it is proposed to raise the following items with the representatives of the Australian Fire & Emergency Services Authorities Council (AFAC) and the committee of AS2419.1;

(i) The requirement to reduce the lowest pressure zone in a building from 50 metres to 35 metres or less. Please note to determine if the a value lower than 35 metres is required to be prescribed the performance of fire appliances across Australia is required to be determined;

(ii) The requirement to provide a normative section indicating that the maximum lift a fire appliance can achieve without loss of performance is three (3) metres (i.e. a maximum of three (3) metres head loss). Please note this will have particular design implications for designers contemplating installing on-site tanks below ground;

(iii) The requirement for a pump-set to serve all fire hydrants in the hydrant design when installed in a building except where ‘unassisted pressures of between 700kPa to 1200kPa can be provide from the on-site tank. Please note this may have particular design implications for high rise designs considering to use cascade systems;

(iv) The requirement to use only listed and certified components in a hydrant design. Please note this will have particular design implications for designers contemplating to use fabricated hydrant booster assemblies that utilise ‘Insert Type Single Point Boosters’;

(v) The possibility of providing concessions for sprinkler buildings within AS2419.1;

(vi) The recommendation that multi-outlet pumpsets be used for relay pumps (and building pumps);

(vii) The requirement to provide a normative section detailing the requirements for pump control

Irrespective of any changes that occur to AS2419.1 in the future as a consequence of the ideas presented in the high rise forum, hydrant designers should always design systems with an understanding that the fire brigade crew that responds to a fire event may be seeing the hydrant design for the first time. Consequently fire hydrant designs need to be reliable, robust, simplistic in design and straightforward to use as they are the primary tool of responding fire brigades and in some situations the last line of defence. One final word – Please reread the warning in the executive summary.


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10 High Rise Forum No 1 – Attendees

Attendees Company

1. Graham Couchman (Sydney Water)

2. Neil McPherson (Watermark Product Solutions)

3. Nicolas Souchaud (Fire Fighting Technologies)

4. Grant Backhouse (Triple M Fire)

5. Rob Bozic (Andec Fire Systems)

6. Neil Lowry Neil Lowry & Associates

7. Paul Raddatz Fire Scope Technologies

8. Ian Stone Warren Smith & Partner

9. Bill Lea Prime Pumps

10. Bill Davis Prime Pumps

11. Justin Benoit George Floth Pty Ltd

12. Jim Allen George Floth Pty Ltd

13. Ian Stalker George Floth Pty Ltd

14. Paul De Las Alas Lincolne Scott

15. Jeffrey Potkins Lincolne Scott

16. Emilia Valkov City of Sydney

17. Graham Easy Andec Fire Systems

18. Simon Mathews Sinclair Knight Mertz

19. Lyle Gardner Repipe


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11 High Rise Forum No 2 – Attendees

Attendees Company

1. Neil McPherson Watermark Product Solutions

2. Terry Doepel

3. Gary Gilbert North Coast Fire Systems

4. Gary Nenadovich GN Consulting

5. Ted Mereweather Eagle Consulting

6. Duncan Glendinning Eagle Consulting

7. Peter Small Lend Lease

8. Graham Couchman Sydney Water

9. David Wood Whipps Wood

10. Brett Ryan Ryan Consulting Group

11. Mark Cummings Eclipse Fire

12. Guy Barwell ITC Group

13. Stephen Wise Defire

14. Vince Caruso CME Engineering Consulting

15. Michael Mason NDY

16. Alan Host Dept. of Planning

17. Scott Harris Hybrid Consulting Services

18. George Pattalis Hughes Trueman

19. Dennis Armstrong Armstrong Consulting Engineers

20. Brett Ruddick Steve Paul & Partners

21. Andrew Guthrie Andrew Guthrie & Assoc.

22. Peter Conroy City of Sydney

23. Bill Davis Prime Pumps

24. Tony Flaherty ACT FB

25. John Wilson ACT FB

26. Peter Stanley ACT FB

27. Jeff Dau ACT FB

28. John Garvin & MFB

29. Tony Meagher MFB

30. Glen Moore WA FESA

31. Daniel Grieg TAS FB

32. Bob Hook QLD

33. Amy Seppelt SA

34. Allan Oates NT

35. Peter Johnson NT

* Please email or post to either address detailed at the front of this document. Thank you

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12 High Rise Forum Feedback

Name: (Not required, but appreciated)

__________________________________________________________ For the questions provided below could you please circle the number that best reflects your feelings or thoughts regarding the high rise forum that you attended.

Number 1: Strongly agree

Number 2: Agree

Number 3: Neither agrees nor disagrees

Number 4: Disagree

Number 5: Strongly disagree

CONTENT 1: Found that the high rise forum met your expectations in regards to the content and material covered

1 2 3 4 5

CONTENT 2: Found that appropriate amount of time was devoted to the content and issues raised

1 2 3 4 5

TIME MANAGEMENT: Found the high rise forum to be appropriately planned, delivered, presented and run

1 2 3 4 5

AMENITY: Found the facilities, amenities and catering met your expectations

1 2 3 4 5

ATMOSPHERE: Found the atmosphere conducive to the exploration of ideas and the airing of concerns

1 2 3 4 5

SATISFACTION 1: Found the high rise forum to be a positive and beneficial experience

1 2 3 4 5

SATISFACTION 2: Would attend other NSWFB run events if afforded the opportunity

1 2 3 4 5

COMMENTS / YOUR OPINION:

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HIGH RISE FORUM SUMMARY PAPER - Fire & Rescue NSW · HIGH RISE FORUM SUMMARY PAPER PAPER PREPARED...

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