Guidelines for Fire Risk Management in Substations

Introduction

This Technical Brochure aims to provide guidelines for substation owners and engineers to manage fire risk continuously with the following intent. Outline of these contents are shown in Figure 1.

• Understand fire risk in substations, including the consequences and potential impact of fire on human safety, property and equipment.
• Summarize effective protection measures to mitigate the fire risk in terms of design, construction, operation and maintenance.

The scope of the brochure includes following contents:

1.  A survey to collect information on fire related experiences in substations. This survey includes the items below in order to capture the current situation concerning risk, impact and countermeasures to fire in substations:

• Number/rates of fire incidents
• Cause, scenarios, measures for fire incidents

2.  Fire risk evaluation to provide guidance on evaluation of fire risk and determining acceptable loss criteria in the case of a fire including:

• Fire scenarios, consequences and probability
• Grid/equipment reliability, cost-benefit analysis for countermeasures

3.  Fire protection design and practices to provide an overview of design methodologies and practices for fire protection with regards to indoor/outdoor/underground/mixed building or equipment fires in substations considering the following points.

• Outdoor (oil spillage prevention, layout design, separation, fire stops etc.)
• Indoor/underground (Alarm/detection system, fire suppression, building structure, safety measures, evacuation route etc.)
• Equipment (transformers, onload tap changers, oil-circuit breakers, capacitors, bushings, new types of assets in/around substations – battery storage, telecom generators etc.)

4.  Fire risk management during construction work

5.  Fire risk management in Operations and Maintenance including:

• Safety measures and rescue procedures (including training)
• Fire plans, coordination with fire authorities
• Mitigation for fire risk around substations
• Wildfire and bushfire risks

6.  Overview of new approaches and available technologies for fire protection as well as new approaches will be discussed with examples of installations provided.

Structure and content of the Technical Brochure

Chapter 1 contains the results of a survey which was conducted to gather details to identify and understand fire risk in substations, including the consequences and potential impact of fire on human safety, property and equipment involving 35 responses from 21 countries worldwide. Chapter 1 also presents the results of a Workshop which collected feedback from the attendees on fire mitigation strategies.

In Chapters 2 and 5, fire risk management methodology is discussed, namely, risk identification (as shown in Figure 3 below) and decision making. These topics are presented mainly to determine acceptable loss criteria in the event of a fire, including risk classification in terms of Total Cost of Risk evaluation. A specific case study on this approach is presented in Chapter 5 taking measures to handle transformer fire risk as an example.

In Chapter 3, fire prevention/mitigation measures are discussed to provide an overview of methodologies and practices in substation lifecycle with regard to indoor/outdoor and underground aspects. These measures cover not only tangible factors (as shown in Figure 4 and 5 below) taken into account mainly at design stage, but also intangible factors mainly at the Operation and Maintenance stage; e.g., training, coordination with fire authorities etc. It is essential to balance intangible factors; i.e. "People", "Process" and "Technology" in order to make physical, tangible factors effective in practice.

In Chapter 4, fire risk management for equipment/material aspects are discussed covering the main points for fire risk management such as insulation materials for the main equipment.

Conclusion

This Working Group was launched to provide guidelines for fire risk management in substations for owners, OEMs, service providers and users. The Working Group members recognize it is essential to secure stable power supply and public safety in any business activities related to substations. Fire risk management is of primary importance since a fire can cause severe equipment damage, threats to public safety as well as impacts on supply reliability. If a utility has experienced a fire incident in a substation, appropriate countermeasures should be developed so that fire incidents would not be repeated by determining the root cause behind the incident and undertaking mitigating measures to avoid repetition.

To control fire risk, it is necessary to apply appropriate measures to all phases of the substation lifecycle. These measures should be continuously reviewed within an organization reflecting lessons learned from their practices, changes in circumstances affecting substations and so on, which we believe is an essential aspect of asset risk management.

In this Working Group , we focused on two main categories of risk management, namely, risk management methodologies and measures to reduce fire risk. The former is to understand and identify fire risk in substations while the latter is to summarize effective prevention/mitigation measures to reduce the fire risk in terms of design, construction, operation and maintenance.