Noise management

Queensland Rail is aware that those living close to our railway lines or within transport noise corridors can experience varying levels of noise.

While noise from the operation of a railway is exempt from environmental nuisance provisions under the Queensland Environment Protection Act 1994, Queensland Rail strives to manage noise associated with its operations wherever reasonable and practical.

There are various sources of noise from a railway and to aid efficient and effective noise reduction, a range of noise management measures are utilised. Find out more below.

How is Rail Noise Assessed?

Planning Levels

Queensland Rail balances the community's need for a safe and efficient transport system with the community's expectations regarding rail noise exposure.

To assist the assessment and management of noise from train operations and fixed facilities like stabling yards, the following Rail Noise Planning Levels are applied:-

New Railway

60 dB(A) assessed as the 24 hour average equivalent continuous sound pressure level (L_Aeq 24 hours)
82 dB(A) assessed as a Single Event Maximum Level

Upgrades to Existing Railway

65 dB(A) assessed as the 24 hour average equivalent continuous sound pressure level (L_Aeq 24 hours)
87 dB(A) assessed as a Single Event Maximum Level

These planning levels are to be assessed 1 metre from the most exposed facade of a Sensitive Place (e.g. a home, hospital, or school).

They are applied as design criteria for new rail infrastructure when Queensland Rail has made a significant change through upgrades to existing infrastructure. A significant change is one that will increase:

Single Event Maximum (SEM) noise levels by 3 dB(A) or more at a Sensitive Place; or
LAeq 24-hour rail noise by 2dB(A) or more at a Sensitive Place.

Single Event or Time Averaged Levels?

The rail noise planning levels are described in two ways.

For a given period of time (from t1 to t2) a noise event will have an overall sound energy (Leq),as represented by the hatched area under the curve shown below. The peak maximum level is the loudest sound during the time period.

Note that the diagram shown is not representative of noise from a train.

The sound exposure level (LAE) is equivalent to the total sound energy, but is 'compressed' into comparable time frames, usually one second. This enables different sound events to be compared.

A noise event of the same volume that goes on for longer will have a higher sound exposure level (LAE) than a shorter noise event. Note however that acoustic averaging is a logarithmic function. It means for example, the addition of two one second 60 dB(A) levels does not combine to be 120 dB(A), instead it averages to a sound exposure level of 63 dB(A).

The Laeq (24 hours) represents average energy exposure accounting for all the rail noise events over a 24 hour period.

By itself, it is recognised the LAeq(24 hour) level is an inadequate indicator of the potential for time varying rail noise to disturb people.

The Single Event Maximum Level provides a way to account for the potential disturbance based on peak maximum levels. Typically on rail lines through urban areas, the Single Event Maximum Level is determined from highest 15 peak maximum levels over a 24 hour period.

Train Horns & Whistle Boards

Horns (including train horns), sirens and bells are used by Queensland Rail to deliver auditory warnings which are vital to ensure the safety of Queensland Rail employees and members of the public.

Whistle boards are strategically located within the rail corridor on the approach to high risk locations such as level and pedestrian crossings, bridges and tunnels. When a train passes a whistle board, the train driver must sound the horn so pedestrians, motorists and track workers know a train is coming.

In order to meet the intended purpose of the horns, these devices must produce sound at a level that can be clearly heard above the general background noise and other potential distractions like personal music players and car radios.

It is not appropriate to apply noise criteria, including the rail noise planning levels, to the auditory warning devices.

A number of level crossings on Queensland Rail’s network have been fitted with Express whistle boards, reducing the number of daily horn activations required in these locations. Express whistle boards area not a viable option for all level crossings, due to rail safety considerations.

Adjacent New Developments

Proposed new developments adjoining the existing rail network may be subject to noise mitigation conditions.

As the responsibility to satisfy such noise mitigation conditions lies with third parties, Queensland Rail will not prioritise further assessment or mitigation for such new developments.

More information can be found at the Department of Transport and Mains Road website.

How is Train Noise Managed?

Passenger Trains

Rail noise is considered as part of the rollingstock investment programs. More detail is available on the Department of Transport and Mains Road website.

Regular maintenance of Queensland Rail’s passenger fleet is undertaken which supports managing noise at source. This includes maintaining wheel profiles to help minimise squeal that may be caused through wheel and rail interfaces.

Freight Trains

Queensland Rail does not own or operate freight services. However, we manage the rail network on which some of these services run. Third party operators who request access to our network must be accredited rail operators and must enter into access agreements with Queensland Rail. These access agreements include matters associated with noise management.

Queensland Rail is obligated to give priority to regularly scheduled passenger transport services. As the vast majority of passenger services operate during the day to satisfy the service needs of the community, most freight train services are required to operate outside of these times.

While careful planning and scheduling maximises the utilisation of available daytime freight paths, it remains necessary that many of the freight train services operate after hours, including overnight.

As the rail manager, Queensland Rail works closely with the freight operators, and provides feedback so that they can investigate and address as applicable, noise related issues that may be associated with their services.

Holding Trains at Signals

Queensland Rail makes every effort to facilitate the uninterrupted passage of freight trains through the Brisbane suburban network. However, due to safety and/or operational requirements, it is sometimes unavoidable that trains be held temporarily at various signals throughout the suburban network.

Where the holding of freight trains is required, every attempt is made to hold them at signals in less populated areas, but there may be occasions when this is not safe or operationally feasible.

Passenger Train Stabling Yards

Stabling yards are located across the rail network, and are used as passenger train storage/parking areas which allow trains to enter into service efficiently across the network to meet timetabled service demand. Trains may also be cleaned and inspected at stabling yards in preparation for entry into service.

Cleaning and inspections usually occur between evening and morning peaks, and it is necessary that power be maintained to the trains and some systems continue to run during these activities. Some noise may be experienced, but every effort is made to keep operational noise to a minimum.

New stabling yards are designed to achieve the Rail Noise Planning Levels for New Railway.

How is Wheel / Rail Noise Managed?

Wheel Squeal

Wheel squeal is the high-pitched noise that can occur as trains travel around curved track. It is primarily caused by friction between the steel wheel and the steel rail.

Queensland Rail's scheduled track maintenance regime includes a program of rail grinding, which assists in reducing noise by providing the optimum interface point between the train wheels and the rail.

In some suitable areas, rail lubricators may also be installed to assist with reducing wheel squeal. The application of a lubricant and/or water along the rail surface further reduces friction between the wheel and the rail, with the benefit of reduced noise.

Regular maintenance of rollingstock, including the optimisation of wheel profiles, also assists with minimising wheel squeal.

Rail Grinding

Rails lose their shape because of wheel impact, acceleration and braking as well as from extreme heat, vibration and general movement. Removing irregularities from worn rails helps to reduce noise which results in a smoother ride and extends the track life.

The machines used to grind the track are up to 180 metres long, nine wagons and weigh up to 650 tonnes. They look a lot like a train but they travel between eight and twelve kms per hour, grinding the rail as they travel.

The grinders can only operate safely when there are no trains operating on the same line. To minimise inconvenience to the thousands of people who travel by train in Queensland each day, the necessary track closures are generally scheduled between the last evening service and the first morning service.

People living close to the rail corridor may hear the rail grinder for a few minutes late at night as it approaches and moves past their properties. In most cases the noise will last only a few minutes.

Times and locations are advertised currently in local papers, and issued via email notification to people living within the affected areas.

To register to receive notifications of rail grinding work in your area, please visit queenslandrail.com.au/EmailNotification

Track Maintenance

In order to maintain a safe, reliable and efficient rail network, it is essential that Queensland Rail carry out track works on a regular basis. The majority of track work is undertaken outside of peak times, mainly overnight or on weekends, in order to minimise the disruption to customers.

During both the planning and delivery of night and weekend works, Queensland Rail aims to reduce community noise impacts, where practicable. Before commencing any noisy night-time or weekend maintenance / construction works, Queensland Rail makes every effort to notify impacted neighbouring communities of the potential disruption.

How are Noise Reduction Works Prioritised?

Where reasonable and practicable, all new railways built by or on behalf of Queensland Rail, will be designed to achieve the Rail Noise Planning Levels for New Railway.

Where rail infrastructure upgrades have the potential to result in a significant change to rail noise levels at nearby Sensitive Places, rail noise impacts will be assessed. If changes to rail noise levels are determined to be significant and are predicted to result in an exceedance of the applicable Rail Noise Planning Levels mitigation measures will be implemented where reasonable and practicable.

Noise associated with the operation of Queensland Rail’s existing rail network is assessed and managed at a network-wide scale. Where feasible, Queensland Rail prioritises the treatment of noise at its source. This approach allows Queensland Rail to deliver a greater benefit to more of its neighbours, than can be achieved through the delivery of fixed mitigation measures, such as noise barriers.

Noise Barriers

Noise barriers are physical barriers designed and constructed to shield properties adjacent to the rail corridor from noise. They may be considered as a suitable mitigation option after all source-based treatments, constructability and safety matters have been assessed.

To be effective, noise barriers must block the line of sight between the noise source and the affected sensitive place. Noise barriers can therefore be a significant visual feature in the local area that may obstruct existing views, reduce breezes, create access issues and attract anti-social behaviour such as graffiti.

Where noise barriers have been identified as an appropriate solution, directly affected property owners need to be consulted. Noise barriers are only constructed in locations where the majority of affected property owners are in favour of their construction.