With no national noise limits to govern railway noise in the UK, understanding the current requirements isn’t easy. Are the current guidelines clear enough?

There is long-established evidence that living in an area with high noise levels can cause stress and sleep disturbance. This can lead to an increased risk of developing serious health problems, including stroke, ischemic heart disease and diabetes. A new study by the UK Health Security Agency (UKHSA) has found railway noise to be a factor in this.

As a result, governments across the globe are working to develop noise regulation standards. In the UK, however, this remains a hazy area, especially in relation to railway noise.

What is noise pollution?

There are many forms of railway noise, and some are more difficult to deal with than others. There are currently no UK national noise limits that railway operators must meet. In legal terms, noise and vibration are both regarded as statutory nuisances in the UK rather than a specific threat to health or safety. From a legal point of view, therefore, the Environmental Protection Act 1990 is the appropriate legislation for dealing with noise pollution. This is enforced by local authorities.

The reasons for this are many – but perhaps the main reason is that, unlike many other pollutants, noise pollution doesn’t just depend on the physical aspects of the pollution itself; it is mainly judged by people’s reaction to it. Looking at it from this point of view, sound only becomes noise pollution when it occurs in the wrong place or at the wrong time, so it makes sense that local authorities are responsible for it.

The railway noise regulation soup

While there is no single UK, European or international standard that covers the overall topic of noise and vibration management on railways, there are numerous standards providing detailed guidance for both construction and operational scenarios.

In the UK, the government’s policy on noise is set out in the Noise Policy Statement for England (NPSE), which aims to “promote good health and a good quality of life through the effective management of noise.” The NPSE is not legislation and local authorities are not legally bound by it. However, Defra (the Department of Environment, Food and Rural Affairs) has an expectation that local authorities will take it into account in relevant situations.

In addition, The Environmental Noise (England) Regulations 2006 require that Defra performs regular noise mapping and develops action plans to mitigate noise hotspots. These Noise Action Plans are produced on a rolling basis and the Department for Transport is responsible for implementing them. In practice, however, implementation is delegated to other rail industry experts, including the Rail Safety and Standards Board (RSSB).

To further confuse the issue, another set of noise constraints are specified in The Noise Insulation (Railways and Other Guided Transport Systems) Regulations 1996. These regulations give trigger levels (measured at the building façade) where residential building noise insulation becomes mandatory. These are:

• 68 dB LAeq*, 0600 – 0000 hours (daytime)
• 63 dB LAeq, 0000 – 0600 hours (night)

Are these guidelines enough?

The multiple policy statements and constraints governing railway noise in the UK result in a hotchpotch soup of guidelines and best practices, often developed by rail associations themselves and enforced by local authorities. In many cases this may be a good thing – the regulations governing urban light rail systems, for example, will need to be different than those governing heavy rail in less populated areas – but it does open up the possibilities for misunderstandings.

Noise pollution is damaging in many ways

Noise and vibration emanating from wheel and track interaction can be heard as squeal, screech, rumbling and hissing to name a few. This noise not only impacts the environment, it indicates even more potential consequences in that the wheel and track are becoming damaged through mechanical wear, fatigue or other failure mechanisms. The underlying causes of this nuisance noise can therefore lead to expensive repairs, affect reliability, impact passenger services and, if left unchecked, become a safety issue with trains ultimately at risk of derailment.

Those mechanisms will be discussed in our next post on rail noise.

*LAeq: indicates the annual average noise levels for the period between 0700 – 2300.

**Lnight: indicates night-time annual average noise levels between 2300 – 0700.

***Lden: indicates a 24-hour annual average noise level, with separate weightings for the evening and night periods.