Substations Fire Protection and Detection Standard

Engineering Standard Electrical

EP 99 00 00 08 SP

SUBSTATIONS FIRE PROTECTION AND DETECTION STANDARD

Version 2.0

Issued May 2010

Owner: Chief Engineer Electrical

Approved by:

Wilfred Leung Chief Engineer Electrical

Authorised by:

Wilfred Leung Chief Engineer Electrical

Disclaimer This document was prepared for use on the RailCorp Network only. RailCorp makes no warranties, express or implied, that compliance with the contents of this document shall be sufficient to ensure safe systems or work or operation. It is the document user’s sole responsibility to ensure that the copy of the document it is viewing is the current version of the document as in use by RailCorp. RailCorp accepts no liability whatsoever in relation to the use of this document by any party, and RailCorp excludes any liability which arises in any manner by the use of this document. Copyright The information in this document is protected by Copyright and no part of this document may be reproduced, altered, stored or transmitted by any person without the prior consent of RailCorp.

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UNCONTROLLED WHEN PRINTED of 32

RailCorp Engineering Standard — Electrical Substations Fire Protection and Detection Standard EP 99 00 00 08 SP

© RailCorp of 32 Issued May 2010 UNCONTROLLED WHEN PRINTED Version 2.0

Document control

Version Date Summary of change August 2007 Last Technical Review

2.0 May 2010 Application of TMA 400 format



Contents

1 Introduction .............................................................................................................................5 2 Scope and Application ...........................................................................................................5

2.1 Scope.........................................................................................................................5 3 References...............................................................................................................................5

3.1 Code of Practice ........................................................................................................5 3.2 International Standards..............................................................................................5 3.3 Australian Standards .................................................................................................5 3.4 Other References ......................................................................................................6

4 Definitions and Abbreviations ...............................................................................................6 5 Fire Risks and Risk Assessment...........................................................................................6

5.1 Particular Fire Risks to Substations...........................................................................6 5.2 The Fire Risk Evaluation Model.................................................................................7 5.3 Fire Risk Rating of substations..................................................................................7

5.3.1 Process ......................................................................................................8 5.3.2 Risk Results Review...................................................................................8

5.4 Full Fire Audit.............................................................................................................9 6 Fire Protection Measures .......................................................................................................9

6.1 General ......................................................................................................................9 6.2 Personnel Safety .......................................................................................................9 6.3 Passive fire protection measures ..............................................................................9

6.3.1 Application..................................................................................................9 6.3.2 Separation ..................................................................................................9 6.3.3 Fire Sealing of Openings..........................................................................10

6.3.3.1 New Substations .......................................................................10 6.3.4 Fire retardant coverings ...........................................................................11

6.4 Active Fire Suppression Systems............................................................................11 6.4.1 General.....................................................................................................11 6.4.2 Active Fire Suppression Options..............................................................11 6.4.3 Active Fire Protection System Selection Matrix .......................................11 6.4.4 Fixed Automatic Aqueous Fire Fighting Systems (Automatic

Fire Sprinkler Systems) ............................................................................14 6.4.4.1 Application ................................................................................14 6.4.4.2 System ......................................................................................14 6.4.4.3 Water Supply for Fire Sprinkler Systems..................................14 6.4.4.4 Water Sprinkler Systems Activation..........................................15

6.4.5 Fire Hydrants Systems.............................................................................15 6.4.5.1 Application ................................................................................15 6.4.5.2 Street Fire Hydrants..................................................................15 6.4.5.3 On Site Fire Hydrant System ....................................................15 6.4.5.4 Water Supply to On Site Fire Hydrant Systems .......................15 6.4.5.5 Hose Reels ...............................................................................15

6.4.6 Gaseous Fire Suppression Systems........................................................16 6.4.6.1 Gaseous Fire Suppression System Activation and

Release.....................................................................................16



6.4.6.2 Safety Precautions for Total Flooding Systems........................16 6.4.6.3 Area Ventilation After Discharge of Carbon Dioxide.................17

6.4.7 Handheld Extinguishers ...........................................................................17 6.4.8 Foam Suppressants .................................................................................17

6.4.8.1 Application ................................................................................17 6.4.8.2 System ......................................................................................18

7 Fire Detection and Alarm Systems......................................................................................18 7.1 Application ...............................................................................................................18

7.1.1 Aspirating Smoke Detection Systems......................................................18 7.1.1.1 Detectors...................................................................................19 7.1.1.2 Monitoring .................................................................................19

8 Fire Services Systems Maintenance...................................................................................19 8.1 General ....................................................................................................................19

Appendix A Fire Risk Evaluation Model – Manual and Guidelines .......................................20 Fire Risk Evaluation Model - Manual ......................................................................................20 Process and Inputs .................................................................................................................20 Outputs 21 Numerical Trigger Points.........................................................................................................22 Definition of Risk Levels..........................................................................................................23 Limitations of Fire Risk Evaluation Model ...............................................................................24 Fire Risk Evaluation Model - Guidelines .................................................................................24



1 Introduction This document describes the minimum mandatory design requirements and practices for fire protection and detection systems in new substations and assessment of fire risks of existing substations in RailCorp.

2 Scope and Application

2.1 Scope This standard covers the fire protection and detection requirements for system and traction substations and sectioning huts and indoor distribution substations in the RailCorp electrical network. It shall be used for selection of appropriate fire protection systems for new substations as well as for upgrading of existing substations.

Selection of fire protection systems shall be based on fire risk assessment using the Fire Risk Evaluation Model (FREM) included in Appendix A. The FREM assesses both the risks of fire due to the condition and configuration of the substation and the consequential risk on RailCorp operations should the equipment or facility be lost.

When applying the standard to the designs for new or modified substations, designers shall check the performance of designs at various stages and determine the fire risk rating for the proposed substation configuration. Where an unacceptable level of fire risk is found to exist in the proposed configuration, passive options to design out the risk should be considered first. Where appropriate active fire protection and detection systems may be incorporated to improve the fire risk rating of substations. However, it is not the intention of this standard to mandate suppression wherever the model identifies a high level of risk. An iterative approach is anticipated where the proposed configuration is analysed using the FREM at appropriate points in the design process and the design adjusted until an acceptable level of risk is achieved.

When applying to existing substations, where the resultant risk levels from FREM are unacceptable the assessor shall investigate the causes of very high and extreme risk levels and using the FREM explore what measures can be undertaken to lower the risks to an acceptable level. Failure to bring the risk levels down to an acceptable level would warrant a full fire safety audit in accordance with AS 4655.

3 References

3.1 Code of Practice Building Code of Australia.

3.2 International Standards BS 5306-4 Fire extinguishing installations and equipment on premises. Specification for CO2 BS 5306-1 Code of practice for fire extinguishing installations and equipment on premises – Part 1: Hose reels and foam inlets

3.3 Australian Standards The following Australian Standards are either referenced in this document or can provide further information.



AS 2118.1 Automatic Fire Sprinklers – general requirements AS 2118.3 Automatic Fire Sprinklers – Deluge AS 4214 Gaseous Fire Extinguishing systems AS 2444 Portable fire extinguishers and fire blankets — Selection and location AS 1851 Maintenance of Fire Protection Equipment AS 2419 Fire hydrant installations AS 2441 Installation of fire hose reels; AS 1603 Automatic fire detection and alarm systems; AS1670 Fire detection, warning, control and intercom systems- System Design, installation and commissioning AS 4655 Fire safety audits NFPA 15 Water Spray Fixed Systems for Fire Protection

3.4 Other References NFPA 850 Recommended Practice for Fire Protection for Electric Generating Plants and High Voltage Direct Current Converter Stations 2000 Edition.

BS 5306-0 Fire extinguishing installations and equipment on premises guide for the selection of installed systems and other fire equipment.

BS 5306-2 Fire extinguishing installations and equipment on premises specification for sprinkler systems. BS 5306-6 Section 6.1 Fire extinguishing installations and equipment on premises foam systems specification for low expansion foam systems.

BS 5306-6 Section 6.2 Fire extinguishing installations and equipment on premises foam systems specification for medium and high expansion foam systems.

Energy Supply Association of Australia D(6) 29-1982 Fire Protection of Electricity Substations; Prepared by Committees 2.3 by Working Group 24 designated as D(6) 29-1982

4 Definitions and Abbreviations For the purpose of this specification the definitions specified in the referenced Australian Standards apply.

5 Fire Risks and Risk Assessment

5.1 Particular Fire Risks to Substations Substations contain a number of features that represent particular fire risks:

• RailCorp’s substations are generally unattended. • The equipment in substations operates at relatively high energy levels. • Some substation equipment contains significant fuel loads. In particular oil cooled

transformers and reactors, and large cable banks contain significant masses of flammable material.

• Cable ducts and conduits can act as paths for oil following a transformer failure. • Unsealed ducts can convey burning oil into adjacent buildings.

Substation fires cannot be attributed to one single cause. This standard does not concern itself with the causes of fire within substations only the required method of detection or extinguishment.



The final determination on whether suppression is required and or detection is dependant on the level of risk acceptable across the network.

5.2 The Fire Risk Evaluation Model Substations contain components and materials that constitute a fire risk.

The Fire Risk Evaluation Model (FREM) included within this standard identifies those configurations, systems and components which contribute to the fire risks within substations.

FREM assesses both the risk of fire due to the condition and configuration of the substation and the consequential risk to RailCorp operations should the equipment or facility be lost.

5.3 Fire Risk Rating of substations The design for new or modified substations shall be checked for fire risk rating using the FREM. Where the output risk levels are unacceptable for a particular design configuration, designers shall investigate the causes for such high risk levels to either eliminate the risks or to bring down the risk levels to an acceptable level by altering the proposed configuration and/or including additional fire protection measures.

This standard shall also be used to identify existing substations in the RailCorp electrical network that have high fire risks. If the FREM indicates an unacceptable risk level the FREM shall be used to explore possible risk reduction measures.

The FREM included in Appendix A of this standard identifies those configurations, systems and components that contribute to the fire risks within substations. The FREM shall be used to rate each individual substation and used to determine what action is required.

When design data for a new sub station or survey data from an existing substation is entered in to the FREM a score is determined. On the basis of the score a risk rating is assigned. These ratings are as follows;

• EXTREME

Where an extreme rating is returned for a new design, features in the design that caused the extreme fire risk rating shall be investigated and addressed in the design.

For an existing substation rated as extreme, the assessor shall immediately notify the Chief Engineer, Electrical Systems. A full audit of the substation is required.

The risk level must be reduced within 3 months. Subsequent inspection must occur within 12 months.

• V HIGH

Where a very high rating is returned for a new design, features in the design that caused the very high fire risk rating shall be investigated and addressed in the design.

For an existing substation rated as very high, the assessor shall immediately notify the Chief Engineer, Electrical Systems. A full audit of the substation is required.

The risk level must be reduced within 9 months. Subsequent inspection must occur within 12 months.



• HIGH

Where a high rating is returned for a new design, features in the design that caused the high fire risk rating shall be investigated and addressed in the design.

For an existing substation rated as high, the assessor using the FREM shall investigate possible cost effective measures to reduce risk level and action within 12 months. Subsequent inspections shall be carried out at two-year intervals.

• MODERATE

Where a moderate rating is returned for a new design, features in the design that caused the moderate risk rating shall be investigated and addressed in the design.

For an existing substation rated as moderate, the assessor using the FREM shall investigate possible cost effective measures to reduce risk level and action within 24 months. Subsequent inspections shall be carried out at four-year intervals.

• LOW

Where a low rating is returned for a new design, the design shall be considered acceptable.

Where a low rating is returned for an existing substation, risk level shall be managed. Subsequent inspections shall be carried out at four-year intervals.

5.3.1 Process Not all possible fire protection measures are necessary for every substation. In order to achieve a cost effective outcome the Fire Risk Evaluation Model (FREM) included at Appendix A. shall be used to guide the selection of a set of measures for each site.

The fire risk rating for each substation shall be determined as follows:

• In the case of existing substations the substation shall be surveyed and data collection input sheets completed on site;

• In the case of a proposed substations the data collection input sheets shall be completed on the basis of the design documentation;

• Collected data on the input sheets to be transferred into the Fire Risk Evaluation Model;

• Review results of the Fire Risk Evaluation Model results sheets to identify those components contributing the rating assigned;

• Asset management and design teams review results and identify most appropriate upgrade measures and or need for full fire audit of the substation.

• The FREM Analysis must be carried out recognising the operational and maintenance equipment configuration that will and do frequently exist at the Substation.

5.3.2 Risk Results Review Where a substation rating is equal to or greater than HIGH further action is required.

The RailCorp risk assessor shall interrogate a copy of the spreadsheet based Fire Risk Evaluation Model and identify those components on the summary sheets with the highest scores.

The input sheets for these high score areas shall be reviewed for reasons why the score is high.



• i.e. A particular substation may be scoring particularly highly because the building is being used to store internal combustion engine operated vegetation control equipment.

The assessor shall interrogate each high scoring field and evaluate those areas where improvements can be made and schedule these in order of complexity and cost to identify those works which can most easily be undertaken.

The assessor shall refer back to the Fire Risk Evaluation Model and having established the order of complexity/cost for the potential improvements introduce these to the Fire Risk Evaluation Model spreadsheet until the risk falls to an acceptable level. Where an acceptable level cannot be reached then the substation shall undergo a full fire audit.

5.4 Full Fire Audit A full fire audit in accordance with AS 4655 shall be undertaken where the Fire Risk Evaluation Model identifies an Extreme risk or where mitigation of Very High Risk is not possible.

The Full Fire Audit shall be an independent audit of the substation to identify RailCorp’s exposure to the risk.

The audit shall include an evaluation of the impact of the loss of the substation including the level of redundancy available, the availability of spare parts and the timeframe required to make the substation operative after a fire.

6 Fire Protection Measures

6.1 General This section identifies fire protection systems appropriate for use in RailCorp system and traction substations. Systems for the passive prevention of fire propagation, and active fire suppression are included. Both systems appropriate for retro-fitting to existing substations and for incorporation in new substations are included.

6.2 Personnel Safety Suppression systems adopted for use on fires involving electrical equipment shall not increase the risk of electrocution to personnel involved in fighting the fire. Water based systems shall only be used within the fire area once all electrical systems have been isolated and made safe.

6.3 Passive fire protection measures

6.3.1 Application Passive fire protection measures shall be provided where the risk of fire spread is identified as too high. The risk is to be assessed with the FREM.

Passive measures shall be adopted in preference to the provision of active systems.

6.3.2 Separation Physical separation between components within substations can provide a good level of protection against propagation and spread of fire. The FREM incorporates input fields associated with the separation of equipment.


Transformers utilising bulk oil shall be physically separated in accordance with the requirements of NFPA 850.

Existing transformers are to incorporate firewalls whilst new installations shall be planned where practical with adequate separation as outlined within NFPA 850. The table extract from NFPA 850 below identifies the separation to be provided for oil filled external transformers.

Transformer Oil Minimum (Line-of-Sight) Capacity Separation without Firewall Less than 1893 L * 1893 L to 18,925L 7.6m Over 18,925 L 15m

Table 1 - Separation of external oil filled transformers

Where separation is not possible a 2 hour fire wall shall be provided in accordance with the requirements of NFPA 850, the following diagram identifies the firewall dimensions. The dimension X is the separation distance and shall be taken from the above table.

* NFPA 850 allows separation distances can be reduced or omitted for transformers with less than 1893L of oil if suppression is provided. Where the content is less than 1893L and separation is to be omitted then the individual transformer arrangement should be assessed as part of a full fire safety audit.

6.3.3 Fire Sealing of Openings All service penetrations including cable ducts and routes shall be fire sealed. Seals shall be made between the cable and the conduit with proprietary fire stops. The stops shall fit tightly around the cable and seal effectively to the conduit. The seals shall not be affected by hydrocarbon products.

Openings into buildings between external transformers and switch rooms shall be closed off with fire board to give a degree of separation equivalent to the surrounding structure.

6.3.3.1 New Substations New substations are to be designed to allow easy inspection of seals and bushes where possible without the need for portable ladders or equipment.



© RailCorp of 32 Issued May 2010 2.0 UNCONTROLLED WHEN PRINTED Version

6.3.4 Fire retardant coverings Where possible fire retardant cables shall be used inside substations.

For existing substations where determined to be necessary by the FREM substation cables shall be coated with an ablative fire covering equal to the “KBS” coating marketed by Projex Group Pty.

The coatings shall be applied along the entire length of the cable and fire stopped at walls and sleeves to stop the spread of fire.

6.4 Active Fire Suppression Systems

6.4.1 General Active fire suppression systems shall be used within RailCorp substation buildings where the risk of fire is too great or the consequences of fire are unmanageable.

Active fire suppression systems shall only be included in the design where it has not been possible to reduce the fire risk to an acceptable level by other means. Where the deployment of active fire suppression systems is found to be necessary to reduce the fire risk rating of a substation, an appropriate system shall be selected in accordance with Section 6.4.3.

6.4.2 Active Fire Suppression Options Active fire suppression system options appropriate for RailCorp substations include:

• Fixed automatic aqueous fire fighting systems; • Hydrant systems for fire fighting purposes; • Extinguishers for first aid fire fighting; • Gaseous suppression systems. • Foam inlets

Many locations in urban areas will have local street hydrants present obviating the need for hydrant systems. Hose reel systems are not to be used for the protection of substations.

6.4.3 Active Fire Protection System Selection Matrix This standard does not mandate the use of suppression systems for all substations and associated equipment. The FREM shall be used to identify those substations where the risk profile must be lowered using active fire protection.

The introduction of fire suppression systems shall be considered only where it has not been possible to lower the substations risk profile by non active or passive measures to an acceptable level. Where risks cannot be reduced to an acceptable level the FREM identifies that a full fire audit is to take place.

The selection matrix identifies those suppression systems suitable for adoption within RailCorp substations. These systems shall be included in the design only after evaluation with the FREM or where required following a full fire audit.


Active Fire Protection System Selection Matrix

Location High Velocity Spray/Deluge Systems

Fire Fighting Hydrants Hose Reels Gaseous Systems Extinguishers Automatic

Fire Alarms

Required for transformers and bulk oil equipment when fire risk or consequential loss too great. System to be provided additionally as exposure protection to/from adjacent public buildings. Boosted tank supply to be provided where no towns main is available

Required to comply with BCA clause E 1.3 To be provided when fire risk or consequential loss too great Boosted tank supply to be provided where no towns main is available

No No Yes Provide to meet requirements of AS2444

Yes for alarm and monitoring of internal equipment. Separate independent system to be provided for control of fire suppression systems

Substation incorporating external transformer in covered compound with internal switch gear.

Substation incorporating external uncovered transformer with internal switchgear

Required for transformers and bulk oil equipment when fire risk or consequential loss too great. Boosted tank supply to be provided where no towns main is available

Required to comply with BCA clause E 1.3 To be provided when fire risk or consequential loss too great Boosted tank supply to be provided where no towns main is available

No No Yes Provide to meet requirements of AS2444

Yes for alarm and monitoring of internal equipment. Separate independent system to be provided for control of fire suppression systems


ering Standard — Electrical tion and Detection Standard EP 99 00 00 08 SP

© RailCorp of 32 Issued May 2010 Version 2.0 UNCONTROLLED WHEN PRINTED

Location High Velocity Spray/Deluge Systems

Fire Fighting Hydrants Hose Reels Gaseous Systems Extinguishers Automatic

Fire Alarms

Internal/Below ground Transformer and switch room

No Required to comply with BCA clause E 1.3 Boosted tank supply to be provided where no towns main is available

No Yes when fire risk or consequential loss too great Novec 1230 only for below ground applications

Yes Provide to meet requirements of AS2444

Yes for alarm and monitoring. Separate independent system to be provided for control of fire suppression systems


No

Yes when fire risk or consequential loss too great CO2 or Novec 1230 allowed above ground.



Ground level single storey switch room


No

Yes when fire risk or consequential loss too great CO2 or Novec 1230 allowed above ground



Ground level two storey switch room

RailCorp EngineSubstations Fire Protec



6.4.4 Fixed Automatic Aqueous Fire Fighting Systems (Automatic Fire Sprinkler Systems)

6.4.4.1 Application Fixed automatic aqueous fire fighting systems (water spray suppressant systems) where required shall only be used on external oil transformers and bulk oil equipment.

Automatic Fire Sprinkler Systems shall be designed to meet the performance requirements of NFPA 15 and AS 2118.

Water spray systems shall be used for the fire protection of the following

• Flammable liquids associated with transformers; • Electrical hazards including outside yard transformers and oil switches;

6.4.4.2 System Water Spray systems where required shall incorporate automatic deluge valve assemblies and open spray nozzles with pipe-work arrays to direct water onto the surfaces of external transformers and bulk oil equipment.

Water spray deluge systems shall be provided to deluge with open sprayers in accordance with AS 2118.3.

The systems shall be operated automatically from heat actuation devices incorporating pilot sprinklers and multiple jet controls (MJC).

The water spray shall be arranged in accordance with AS 2118.3 to impact the surfaces of a transformer and bulk oil equipment or store to provide both cooling to the components but also form an emulsified water and oil mixture unable to ignite or burn.

The water spray systems shall provide complete water spray impingement on all exposed exterior surfaces of the equipment in accordance with NFPA 15.

Where there is insufficient space to install water spray nozzles beneath transformers water shall be introduced from the sides by horizontal nozzles.

Manual release controls for the deluge systems shall be provided at booster valve stations and the control valve assemblies to allow activation by the brigade.

6.4.4.3 Water Supply for Fire Sprinkler Systems Water based fire suppression systems shall be served from the local water mains with a fire brigade booster inlet to allow the brigade to boost the water supply to the system. Where a substation is remote from water mains water storage tanks and diesel backed pumps shall be provided to supply the suppression systems. Storage volumes and pump installations shall be in accordance with AS 2118 and shall have the capacity to maintain the supply of water to the fire for no less than 1 hour.

Where the town water mains have insufficient water supply pressure or flow but adequate reserves to continue supply for not less than 1 hour then a water booster pump-set(s) shall be provided to boost the pressure from the town mains. The pump-set(s) shall be provided in accordance with AS 2118.



6.4.4.4 Water Sprinkler Systems Activation Water spray systems shall be activated automatically with fusible links or bulbs, in accordance with AS 2118.

The water spray suppression system shall be monitored with flow switches to signal activation to the RailCorp electrical SCADA system.

6.4.5 Fire Hydrants Systems

6.4.5.1 Application Fire Hydrant Systems shall be used to fight substation fires only after full electrical isolation.

6.4.5.2 Street Fire Hydrants Many locations in urban areas will have local street hydrants present obviating the need for additional hydrant systems.

Street fire hydrants shall be provided in accordance with the Building Code of Australia (BCA) and AS 2419 for:

• Buildings with an area greater than 500m² • Where a fire brigade is available to fight fires.

Street hydrants shall be within 70m of a substation building or enclosure requiring protection under the BCA.

6.4.5.3 On Site Fire Hydrant System On site fire hydrant systems where required shall be provided in accordance with AS 2419.

6.4.5.4 Water Supply to On Site Fire Hydrant Systems Hydrant system water supplies shall be adequate for meeting the system demands in accordance with the requirements of AS 2419.

Where the local mains pressure and flow cannot meet these requirements a boosted water supply shall be provided in accordance with AS2419 incorporating storage tanks and pumps.

The on site hydrant system shall be served from a diesel driven pump-set dedicated to the site.

A fire brigade booster inlet shall be provided to allow the brigade to boost pressures on site when required.

Remote non mains fed hydrant systems shall be provided with tanks and pumps to maintain water supplies for 4 hours in accordance with AS 2419.

6.4.5.5 Hose Reels Hose reels shall not be provided within substations.



6.4.6 Gaseous Fire Suppression Systems Gaseous fire suppression systems shall be in accordance with AS 4214.

The gaseous agents shall be selected from the following;

• Carbon Dioxide (low pressure refrigerated C02 ); • FM200 (Halocarbon) HFC-227ea; • Novec 1230 Fire Protection Fluid.

Reduced levels of oxygen within protected spaces following discharge can have adverse effects on personnel within the rooms and enclosures. Warning signs shall be affixed in prominent locations detailing the suppressants used and the operational safety requirements. Audible and visual warning alarms shall operate to warn occupants to evacuate the protected risk area upon fire detection.

The systems shall incorporate bottled supplies of extinguishant and delivery pipework to the hazard discharge heads provided within the hazard area in accordance with AS 4214.

Manual lock-off station(s) shall be provided for isolating the systems during maintenance or other occupied periods.

Carbon dioxide gas is heavier than air and will fall to the bottom of the enclosures it is discharged into and flood around the different equipment. The injection of CO2 will displace air from within the enclosure. Adequate venting shall be provided to ensure over pressurisation of the enclosure does not occur compromising the stability of the enclosure.

Detection systems provided to activate gaseous fire extinguishing systems shall be in accordance with the requirements of AS 1670 and the Building Code of Australia.

Detector systems shall comply with AS 1603.

Detection systems provided to operate a fire extinguishing systems shall be linked back to the RailCorp electrical SCADA system.

6.4.6.1 Gaseous Fire Suppression System Activation and Release The fire suppressant gas shall be released after a pre-determined time delay to ensure staff have left the area or to allow for investigation by security staff.

Pre discharge alarms shall be provided within the spaces protected with double knock detection. Stop gas stations at entry points to the protected area shall be provided to abort the gas discharge if required.

6.4.6.2 Safety Precautions for Total Flooding Systems Carbon Dioxide and gaseous suppressants are/can be suffocating gases and the safety requirements set out in AS 4214 and BS 5306 Pt 4 shall be complied with.

Following safety precautions for total flooding systems are recommended in BS 5306 Pt 4.



Occupancy Door Lock Changeover Switch (1)

Automatic/ Manual Changeover Switch (2)

Manual Valve (3)

Auto Valve (4)

System Status Unit (5)

System Isolated Lamps (6)

Normally occupied Yes Yes Yes or

(4) Yes or (3) Yes Yes

Not normally occupied Recommended Yes or (3) Yes or

(2) Optional Yes Optional

Door lock changeover switch (1) shall include an internal escape override. A contacted keep as opposed to a contacted lock shall be used. Manual valve (3) is a monitored manual only valve sited in the supply line from the carbon dioxide containers. Automatic valve (4) is monitored normally closed valve sited in the supply line from the carbon dioxide containers that will open only on receipt of a signal from the detection system or manual release system. A means of manual operating the valve shall be provided. A means of isolating the valve shall be provided.

6.4.6.3 Area Ventilation After Discharge of Carbon Dioxide A means of mechanically or naturally ventilating areas after discharge of carbon dioxide shall be provided.

The standard BS 5306 Pt 4 dictates that the means provided for ventilation should not form part of the normal building ventilation system and should incorporate extraction arrangements at low level in the protected area. Care should be taken to ensure that the post-fire atmosphere is not ventilated into other parts of the building.

6.4.7 Handheld Extinguishers Extinguishers shall be provided for first aid protection within transformer rooms and substations. Extinguishers are not to be considered anything more than a first line of defence against coincidental fires during personnel occupation.

Personnel shall not attempt to tackle a fire unless they are competent to do so and are confident that it can be handled with the first aid protection devices available.

Extinguishers shall be provided in accordance with AS 2444 and maintained in accordance with AS1851. Extinguishers shall be located at entrances and on escape routes from the rooms and in all instances no further than 20m from the fire risk.

6.4.8 Foam Suppressants

6.4.8.1 Application The NSWFB carries Aqueous Film Forming Foam (AFFF) on its fire trucks in 20 litre pails for use on oil and flammable liquid type fires.

The NSWFB fire trucks incorporate foam induction equipment on the pump and AFFF foam making branches for fire hoses.

Fire fighting foam inlets shall be provided on below ground bulk oil transformers and equipment rooms where the risk is too high. The level of risk is to be assessed with the FREM.



Foam inlet systems shall only be introduced into below ground substations following agreement with the NSWFB.

6.4.8.2 System Foam inlet systems shall be provided in accordance with BS 5306 Pt 1.

Inlets shall be positioned with their centre line 400 to 600mm above ground level. The inlet breechings shall be located within a box on the face of the building clearly marked with the words “Foam Inlet to Transformers” in red letters no less than 25mm high.

The foam inlet pipework shall be heavy grade steel 80mm diameter with a fall to the transformer chamber.

The pipework route shall be less than 18m in length. Inlet locations shall be agreed with the NSWFB.

Foam inlet systems shall only be manually operated by the NSWFB.

An audible alarm shall be incorporated to warn personnel of activation prior to discharge.

7 Fire Detection and Alarm Systems

7.1 Application Automatic detection systems shall be provided within substation switchrooms in accordance with the Building Code of Australia and AS 1670.

Detection systems provided within substation switchrooms shall be air sampling systems in accordance with AS 1670.

7.1.1 Aspirating Smoke Detection Systems Air sampling aspirating smoke detection and alarm systems shall be provided within substation buildings.

RailCorp substations incorporate equipment which when operating can cause ionised gases to be produced. This can cause sensitive smoke detection systems to go into alarm erroneously.

The generation of ionised gas is a normal bi-product of the substations operation and false alarms within detection systems in response to this can lead to complacency.

Air sampling systems shall be provided within the substation buildings to monitor for smoke. The detection zones close to the equipment likely to cause ionisation shall have their sensitivity set so as to minimise false alarms.

The system shall be configured so that two separate sensing zones have to alarm before alarm signals are raised. One sensing zone is to be local to the equipment the other remote.

The air sampling systems shall have the following alarm levels.

a) Stage 1 - Initial detection. Signal to SCADA system.

b) Stage 2 - Alarm to SCADA System recommending investigation/ evacuation.

c) Stage 3 - Full alarm. Operations centre evaluate alarm.



d) Stage 4 - Intervention by brigade. The detection devices shall be fully monitored for alarm and/or fault condition to ensure reliable service and to transmit a fire alarm signal to a monitored emergency control centre.

7.1.1.1 Detectors Smoke detectors shall be multipoint aspirated smoke detectors (MASD) within air sampling systems.

7.1.1.2 Monitoring Fire detection systems at substations shall be linked back to the central control centre on the RailCorp electrical SCADA system.

8 Fire Services Systems Maintenance

8.1 General Fire suppression and detection systems require ongoing inspection, testing and maintenance to ensure their continued functionality.

Technical Maintenance Plans including tasks for inspection, testing and maintenance of fire systems incorporated into substations shall be developed in accordance with the RailCorp Maintenance Requirements Analysis Manual (MRAM) and AS 1851 Maintenance of fire protection systems and equipment.



Appendix A Fire Risk Evaluation Model – Manual and Guidelines

Fire Risk Evaluation Model - Manual The Fire Risk Evaluation Model included in this standard is a risk evaluation tool designed to rank the different fire risks and systems within substations against each other to yield a score for the substation. The model assesses both the risk of fire due to the condition and configuration of the substation and the consequential risk on RailCorp operations should the equipment or facility be lost. It can be used to evaluate risk rating of new substation designs and existing RailCorp substations.

The tool evaluates whether risks are high within a substation and gives the user the opportunity to test why the substation scored badly. It allows the user to adjust the various input fields to improve the risk rating i.e. a particular substation may score badly because it has many cable conduits that are not fire stopped, the tool will allow the user to introduce such protection measures and see the substations rating improve.

The introduction of fire suppression systems within substations will be costly and the Fire Risk Evaluation Model allows each substation to be methodically tested for other more cost effective measures before the decision to introduce suppression is made.

The suppression systems adopted for use on fires involving electrical equipment must not increase the risk of electrocution to personnel involved in fighting the fire. Where water based systems are used all components within the fire area must be isolated and made safe prior to activation.

Process and Inputs In using the fire risk evaluation model, RailCorp staff will be required to attend the sites nominated and provide inputs into the model.

Within the assessment sheets there are categories that are flanked by boxes. Depending on the equipment found in the substations, the boxes must:

• be marked with the numeral “1” • where the red box is located next to the main heading, only 1 box in line can be

marked. • When more than 1 box is checked and is not permitted, conditional formatting has

been introduced and all boxes will turn red to indicate an input error. This is shown below.

RAILCORP SUBSTATION FIRE RISK SITE INSPECTION SHEET SUBSTATION Master DATE ADDRESS INSPECTOR FUNCTION Traction 1 Distribution 1 System 1 LOCATION Surface Underground

• When loading data into the model, input data into the “Site Sheet” (Sheet 1) first. Common fields will then be automatically input to other sheets.



Outputs

Once the assessment sheets are completed, the output sheet will have calculated numbers under the following headings:

SUB STATION Master

RESULTS SHEET

EQUIPMENT / FIRE SOURCE FIRE RATING RESIDUAL

RATING IMPACT HEALTH

& SAFETY

High Voltage Switchgear 4.7 4.2 4.7 Rectifier Transformer 6.9 6.8 0.7 Rectifier 0.0 0.0 0.0 System Transformer - 33kV 0.0 0.0 0.0 System Transformer - 11kV 17.9 17.6 17.9 System Transformer - 2kV 0.0 0.0 0.0 Reactors 0.0 0.0 0.0 1500 V DC Switchgear 1.0 0.9 0.3

EQUIPMENT / FIRE SOURCE FIRE RATING RESIDUAL

RATING IMPACT HEALTH

& SAFETY

Medium Voltage Switchgear - 11kV 8.4 7.6 8.4 Medium Voltage Switchgear - 2kV 0.0 0.0 0.0 Dist / Auxillary Transformer 0.0 0.0 0.0 Cables 0.0 0.0 0.0 Miscellaneous Electrical Items 0.1 0.1 0.1 Battery System 0.0 0.0 0.0 Low Voltage and Control Equipment 0.0 0.0 0.0 Incidental Plant and Equipment 0.0 0.0 Surrounding Environment 1.3 1.2 Diesel Generator Exhaust 0.0 0.0 Vehicle Impact 0.0 0.0



The final numbers that have been calculated under the following headings have been graded in terms of relative risk as follows:

FIRE RATING RESIDUAL RATING IMPACT HEALTH &

SAFETY

TOTAL for SUB STATION 40 38 32 132

RISK LEVEL MODERATE MODERATE MODERATE V-HIGH DISRUPTION 40 32 MODERATE MODERATE REDUNDANCY FACTOR

40

32

MODERATE MODERATE

The following headings are defined as follows:

Fire Rating The raw or total risk rating for the substation ignoring any fire detection and suppression that may be installed.

Residual Rating The risk rating allowing for the benefit provided by fire detection and suppression systems.

Impact The risk rating (based on the residual rating) modified for the level of spare parts or built in redundancy for this substation.

Health and Safety This the level of overall risk posed by the emergency egress facilities provided in the substation.

Disruption The Impact risk rating modified by the number of lines that would be affected by the loss of the substation.

Redundancy Factor The Impact risk rating modified by the level of redundancy provided by substations either side of the station being analysed.

Numerical Trigger Points The 5 risk levels that could originate under the following headings and are triggered on achieving the following numbers for the below categories

FIRE RATING RESIDUAL RATING IMPACT

< 10 – Low Risk

< 50 – Moderate Risk

< 100 – High Risk

< 500 – Very High Risk

> 500 – Extreme Risk



The 5 risk levels that originate under the following heading is triggered on achieving the following numbers:

HEALTH & SAFETY

< 50 – Extreme Risk

< 150 – Very High Risk

< 300 – High Risk

< 600 – Moderate

> 600 – Low Risk

Definition of Risk Levels FREM assesses both the risk of fire due to the condition and configuration of the substation and the consequential risk to RailCorp operations should the equipment or facility be lost. When design data for a new sub station or survey data from an existing substation is entered in to the FREM, following risk ratings will be assigned by the program to the substation assessed:

• EXTREME

Where an extreme rating is returned for a new design, features in the design that caused the extreme fire risk rating shall be investigated and addressed in the design. For an existing substation rated as extreme, the assessor shall immediately notify the Chief Engineer, Electrical Systems.

• V HIGH

Where a very high rating is returned for a new design, features in the design that caused the very high fire risk rating shall be investigated and addressed in the design. For an existing substation rated as very high, the assessor shall immediately notify the Chief Engineer, Electrical Systems.

• HIGH

Where a high rating is returned for a new design, features in the design that caused the high fire risk rating shall be investigated and addressed in the design. For an existing substation rated as high, the assessor using the FREM shall investigate possible cost effective measures to reduce risk level and action within 12 months. Subsequent inspections shall be carried out at two-year intervals.

• MODERATE

Where a moderate rating is returned for a new design, features in the design that caused the moderate risk rating shall be investigated and addressed in the design. For an existing substation rated as moderate, the assessor using the FREM shall investigate possible cost effective measures to reduce risk level and action within 24 months. Subsequent inspections shall be carried out at four-year intervals.


© RailCorp of 32 Issued May 2010 2.0 UNCONTROLLED WHEN PRINTED Version

• LOW

Where a low rating is returned for a new design, features in the design that caused the low risk rating shall be investigated and addressed in the design. Where a low rating is returned for an existing substation, risk level shall be managed. Subsequent inspections shall be carried out at four-year intervals.

Limitations of Fire Risk Evaluation Model This section defines the limitations of the application of the results. In this context, assumptions are defined to be inputs to the assessment, which may include simplifications of reality, based on engineering judgement or accepted approaches that are necessary to enable the issues in question to be rationally addressed.

These inputs are spelt out in order that users of the tool are made aware of them and there applicability can be reviewed. Limitations are defined as boundaries to the applicability of the results, including aspects, which have been excluded from consideration.

Any audits and subsequent outputs do not include:

• Detailed design • Implementation of the results of the study • Ongoing inspections • Certification, commissioning or maintenance of systems. • Involvement in an appeals process of a peer review process • Gaining building approval • The fire risk assessments and the reports do not constitute an audit in accordance

with AS4655 or any other relevant Australian Standard. • The fire and risk assessments to not constitute a BCA compliance/due diligence

assessment. • The fire and risk assessment tool does not constitute a fundamental Fire

Engineering Assessment or Quantitative Risk Assessment of absolute risk • The fire and risk assessments do not constitute an OH&S audit. • The tool is limited to inspections of substations for collection of specific data to go

into a relative risk tool for specified corporate purposes.

Fire Risk Evaluation Model - Guidelines Table in the following pages provides the users of the Fire Risk Evaluation Model guidelines to the correct interpretation of terms used in the audit sheets that provide input to the risk evaluation model. Assessors of a particular site or a design shall first familiarise with these terms and their proper interpretation to obtain a consistent risk rating of substations when using the model.


RAILCORP SUBSTATION FIRE RISK SITE INSPECTION SHEET - GUIDELINES AND DEFINITIONS

Sheet Number

Main Category

Sub Category

2nd Category

Comments

1 SITE DETAILS FUNCTION Traction Traction substations will have a rectifier within it. Distribution Distribution substations converts high voltage to low

voltage.(415/120V) System System substations transformers or switches high

voltage only. They have no rectifiers within them. LOCATION Surface The substation is totally above ground. Underground The substation is below ground and in some cases

form part of a main train station Surrounds Surrounded The substation is within a built up area and

predominantly surrounded by residential development.

Partial The substation is partially surrounded by development. An example of this would be residential or commercial adjacent to rail corridor.

Open Area The substation is within a suburban environment but not surrounded by development.

Rural/Bushland A substation that is within a well timbered area or open plains with no development surrounding it.

Assessed Risk Bushfire Substation is located in bushfire prone area. High Risk Information on risks to location from miscellaneous

outside agencies. This does not include risks due to the equipment itself.

Low Risk Information on risks to location from miscellaneous outside agencies. This does not include risks due to the equipment itself.

VEHICLE IMPACT Vehicle Impact Main Road Speed limit >60kph and or heavy traffic. On Bend/Junction Location of substation located on a bend of a main

road. No buffer Substation is located bounding roadside. Quiet Road Speed limit <60kph and low volumes of traffic.



RAILCORP SUBSTATION FIRE RISK SITE INSPECTION SHEET - GUIDELINES AND DEFINITIONS Sheet

Number Main Category

Sub Category

2nd Comments Category

SURROUNDS Vegetation >6m Clear Vegetation such as grass, trees, that are greater than 6m away from a building or nearest piece of equipment or fuel source. Vegetation does not include mown grass or small trees or potted plants. If the area has a dense coverage of grass, trees etc then these should be mentioned.

<6m Clear Vegetation such as grass, trees, that are less than 6m away from the building or nearest piece of equipment or fuel source. Vegetation does not include mown grass or small trees or potted plants. If the area has a dense coverage of grass, trees etc then these should be mentioned.

Residential >6m Clear Residential properties consisting of dwellings, town houses, or hotels greater than 6m from away from a building or nearest piece of equipment or fuel source.

<6m Clear Residential properties consisting of dwellings, town houses, or hotels less than 6m from the building or nearest piece of equipment or fuel source.

Industrial >6m Clear Industrial premises such as car yards, paints shops, manufacturing, warehouse.

<6m Clear Industrial premises such as car yards, paints shops, manufacturing, warehouse.

Combustible Examples may be a tyre storage facility, warehouse or others with high fuel load.

High Risk Examples may be Paint shops, car repairs where large quantities of flammable materials (especially liquid or gases) are kept.

EMERGENCY SERVICES Ease of Finding Visible Visible from the road without signage. Clear Signs Signage to the substation from the road is in place. Road Access All Weather Bitumen or sealed road. Access not a problem for any

emergency vehicle. >One Road Alternative access into the substation. Applicable in

remote locations.





Sub Category


Height/Width Restrictions Would emergency vehicles have to go underneath a rail bridge for example. Is the road width available for say a fire appliance (>5.0m)

BUILDING ONE,TWO,THREE

Construction Brick and Timber Construction of the substation consists of brick walls and timber roof components such as trusses, timber framing and the like. Inspection of ceiling space may be necessary. Structure has combustible load.

Timber Timber construction throughout. Non-combustible Brick walls, metal and/or tiled roof and no timber in

the roof or internal walls. Main Level Alt Egress Alternative egress could be provided in addition to the

exit on the main floor. Into Open Egress to outside of building. Upper floor area Ancillary Rooms/areas Flammable Able to contain materials that are flammable including

flammable aerosols, liquids and the like stored in a room or cabinet.

Office/area Office fuel load would consist of desks, chairs, filing cabinets and compactors.

COMPOUND 1 & 2 Egress Route The compound is a noted egress route from the building.

Refuge Could be an area remote from the building within the compound where someone could take refuge from a fire within the building, or equipment in the component.

Gate/Door Gate is provided within the compound fencing. Locked The gate is locked for security purposes. Keys should

be carried with personnel at all times. HOUSEKEEPING General Area Excellent All materials are stored in a designated place. Exits

are not obstructed. Compound has grass mowed if present. No rubbish is present.





Sub Category


Average Some areas of the above criteria are present. Poor All areas in the above criteria are not evident. SECURITY Patrol Regular patrol/inspection by internal/external

personnel that would be able to detect an early stage of fire. Patrols would occur regularly but they must occur several times a day, every day.

Monitored Doors This refers to the doors into the actual buildings and does not include gates in perimeter fences.

CCTV This means that it is not monitored but pictures go to tape. If the signal goes back to a control room that is constantly monitored this should be indicated by ticking the monitored box.

FIRE CONTROL Suppression Emulsifiers - High Velocity Jets This system would be only present in outdoor bunded areas where oil would be present. They would stop the oil from burning and spreading. They would not be located inside the building.

Hose reels 36m fire hose reels are located in the substations Extinguishers Portable fire extinguishers suitable to the risk of fire

are provided. Eg CO2, Foam etc. Hydrants Hydrant points - there may be standpipes within the

building near the exits, outside near the exits or there may be a tapping outside the compound.

Detection VESDAS Aspirating smoke detection system that will have plastic pipes with sampling points.

SERVICES High Voltage 132, 66 or 33kV Medium Voltage 11 or 2kV Low Voltage 415, 240 or 120V Tracks Served Number of single tracks. REDUNDANCY Impact on Service None No impact on train service Peak Peak services cannot run at peak levels (both trains

and loading) but can run at off peak train frequencies and loadings.





Sub Category


Off Peak No services can be supported over this section of the line.

2 HIGH VOLTAGE SWITCHGEAR

LOCATION Indoor/Outdoor Where equipment of a single type (eg transformers) are located both indoors and outdoors, and there is no provision to select something other than indoors or outdoors, then always select indoors. Where there are two sections for the same type of plant, and if there is not two sizes of that plant (piece of equipment), then it is OK to use one section on the data capture sheet for the indoor equipment and another for outdoor equipment.

Nearest Fuel Source Nearest combustible item which could include building or equipment.

CONSTRUCTION Bunding All Individual Separate bund for each piece of equipment. All combined One bund serving all pieces of equipment. Partial Some bunding may be present. Underground Sump Single Single sump for all pieces of equipment. Individual Individual sumps for all pieces of equipment. Partial Some sumps may be present. CONFIGURATION Isolated Stand alone breakers. Single S/Board All breakers in one switchboard. Many S/Boards More than one individual, separated switchboard, with

each switchboard containing more than one breaker. SPARES Complete Breakers Onsite On site but not connected. >1 More than one on-site and not connected. Off site Off site >1 More than one off site. RECTIFIER QUANTITY Installed Installed and connected. Needed For Load Required to provide maximum traction power.





Sub Category


RECTIFIER TRANSFORMER

LOCATION 3 SYSTEM TRANSFORMER (to 33kV) Step down to 33kV From 132 or 66kV (to 11kV) Step down to 11kV From 66 or 33kV (to 2kV) Step down to 2kV From 33 or 11kV LOCATION Tx Separation This is the distance between like transformers. 1500 Volt DC

SWITCHGEAR

5 HV AND DC POWER

CABLES

MAIN ROOMS, BELOW MAIN ROOM, OUTDOORS

Cluster -Horizontal Type A,B C, D 3 or more cables laid horizontally half a cable diameter apart, containing the following types: Type A Cables - Pressurised Nitrogen Type B Cables - Oil impregnated paper insulated with lead sheathing, flame retardant halogen free R-HF Type C Cables - Mineral Insulated Non Draining (MIND), PVC sheathing, PIMIND (Mass Impregnated Mineral Oil Non Draining) Type D Cables - XLPE with PVC/HDPE, XLPE with megalon, modern XLPE insulated cables, modern PVC/PVC insulated cables, vulcanised Indian rubber, EPR (Ethylene-propylene rubber), XLPE/HD,

Cluster - Vertical Type A,B C, D As above - but vertical. Cable types refer above Cableway - Horizontal Type A,B C, D Located on horizontal cableway with proper

separation distances. Cable Types refer above Cableway - Vertical Type A,B C, D As above - vertical. Cable Types refer above Chase/Trench Located in trench. Cable Types refer above





Sub Category


PENETRATIONS Penetration from one room to another that are not properly sealed. Holes in walls are to be taken as a path for fire and the distance between a piece of equipment and a fuel source (or similar piece of equipment) should be measured through the hole. The hole has to be a reasonable size such that fire and heat could pass through the hole. Proper sealant used.

CABLE JOINTS Number of cable joints present. EXTRA FUEL LOAD Adjacent to Cables Any combustible material near (<1m) to cables. Oil into Trench Is it possible for oil to drain/leak into trench. PROTECTION Cable Coating Have cables been separately coated with fire

protection material. ENERGY DISSAPTING

RESISTORS

QUANTITY Installed These resistors will generally only occur on the blue mountains line.

AIR BLAST AIR BREAK SWITCHES

Size Most of the substations will have both 66kV and 11kV

6 BATTERIES AND SYSTEMS

LOCATION Location Separate Room Completely separate room within building with door. Common Areas In building but not isolated. FUEL SOURCE Near Batteries Timber/Solid Timber/combustible material within 2m of battery or

within the separate room. Liquid/Gas As above but flammable liquids or gases. INCIDENTAL PLANT &

EQUIPMENT

GENERATOR Exhaust Inside Flue exhausts inside the building.





Sub Category


Outside Flue exhausts outside building. Fuel Source Any fuel source (<2m) of flue outlet. MOBILE PLANT Motor Vehicles Motor Vehicles permanently stored on site NOTES

Refer to Manual for Input requirements into the model.


Substations Fire Protection and Detection Standard

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Transcript of Substations Fire Protection and Detection Standard