Thursday, April 28, 2022
ONRSR is reminding rail transport operators about a range of risks, causes and controls associated with fires in underground tunnels and stations (FTUGs).
FTUGs can result in catastrophic loss of life although this is not the case for the vast majority of fires due to the effectiveness of fire safety controls.
RTOs should continue to identify new potential safety controls and make an assessment as to whether they are reasonably practical to implement as well as reviewing their current operations to ensure that existing fire safety controls are in place and effective.
Given fire safety is a specialist discipline, RTOs may be required to engage recognised fire safety specialists to accurately determine risk levels and determine which controls are appropriate for specific rail networks and operations. This may also be required to determine appropriate methods for demonstrating compliance to fire safety standards. Fire safety specialists should also be engaged to assess the impact of any proposed modification to rail infrastructure that may have an impact on fire safety.
ONRSR’s review into FTUGs identified causes and contributing factors across the four areas listed below. While not exhaustive and given the range of operational environments within the Australian rail industry, the following causes, contributing factors and controls should be noted.
The causes of FTUGs can be classified into organisational, technological or equipment factors, and individual factors.
1. Organisational factors e.g.
2. Technological or equipment factors e.g.
3. Individual factors e.g.
While not exhaustive and given the range of operational environments within the Australian rail industry, the following controls should be noted. RTOs must consider a range of factors, including the likelihood of the hazard and the degree of harm to determine what controls are reasonably practicable to implement (see the ONRSR Guideline – Meaning of duty to ensure safety so far as is reasonably practicable SFAIRP for more information).
There is no single control that can be implemented that can eliminate fires in tunnels and underground stations. While not eliminating the risk, implementing the following controls can however reduce the risk.
Removing fire loads or controlling the amount of combustible material permitted in a tunnel or underground station reduces the risk of fires propagating. This includes:
RTOs have employed a variety of engineering controls which can be categorised into the following five (5) groups.
1. Compartmentation controls are designed to inhibit the spread of smoke, fire, heat as well as ensuring structural integrity within an underground station. Dividing the station area into a series of ‘fire tight boxes’, termed compartments, limits the spread of fire, helps people evacuate and allows emergency services to undertake rescue operations. Examples of compartmentation controls include but are not limited to:
2. Fire suppression system controls apply chemicals or fluids on fires to limit their spread. Examples include but are not limited to the following:
3. Ventilation controls control air flow underground stations and tunnels. They provide clean air for egress paths and routes, cross passages, safe places, including pressurisation; removing exhaust smoke and hot gasses safely away from people; and prevent/control the spread of smoke. Examples include:
4. Fire detection systems enable detection of fire during its early stages before it begins to spread. Examples include:
5. Escape and Refuge controls provide a safe place for people to escape and exit, or seek refuge, until it is safe for them to escape. Examples include:
Operators have employed a variety of administrative controls to minimise the risk of fire in tunnels and underground stations which can be categorised into two (2) groups.
1. Public communication system controls are controls which alert people to the risk of fire and direct them to a place of safety. Examples include:
2. Emergency services and management systems controls include:
Many of the above controls are required as part of codes and standards which include, but are not limited to the
This information is provided as guidance only and may not be applicable to all rail transport operators.