We know that noise is a very important issue for communities around the airport.

*This page contains one (1) question located within the “Have your say” section at the bottom of the page.


Noise effects of the airport today are primarily caused by the flights arriving and departing. Despite an increase in the number of flights over the past few decades, our noise contour footprint (see below for details on ‘noise contours’) has shrunk considerably and it is currently smaller than it has ever been.

Noise from arriving and departing aircraft can affect our local communities and we need to continue to manage noise effectively now and with the expansion of the airport.

We want to take the opportunities presented by expansion to adapt and improve some of the ways we currently manage noise.

To mitigate noise effects, we are developing improvements to how we use the runways. This includes:

We have also embedded in our design things like displaced landing thresholds and noise barriers to protect the closest communities from ground noise at the airport.

Noise today

Heathrow currently uses a range of different measures to manage and reduce noise. The complete package of existing measures can be found in the Noise Action Plan 2019-2023 and is available on the Heathrow website (

What are steeper approaches and how to they reduce noise?

Steeper approaches mean aircraft on their approach to the airport follow a steeper descent than current procedures. This means aircraft are higher which reduces noise levels on the ground.

What are displaced landing thresholds and how do they reduce noise?

Displaced landing thresholds allow aircraft to land further down the runway, which means that they are higher as they approach the airport at all distances from the airport. This reduces noise at ground level.

Noise policy and presenting noise information

A noise contour is either a line on a map that represents equal levels of exposure to noise or an area on a map within which exposure to noise is greater than a specified value. We have published our noise contours annually for many decades and the 57 dB(A) Leq daytime contour has been used to track our noise performance over time. The terms db(A) and Leq are described on the below.

Over the last few years, government noise policy has tightened. For our DCO and airspace change proposals we are now required to provide details of:

  • noise effects where aircraft fly below 4,000 ft;
  • noise information (in airspace change proposals only) where aircraft are between 4,000 and 7,000 ft;
  • noise effects on health and quality of life where noise exceeds the following:
  • Lowest Observed Adverse Effect Levels (LOAELs), defined by Government as 51 dB(A) Leq during the day and 45 dB(A) Leq at night;
  • Significant Observed Adverse Effect Levels (SOAELs);
  • Unacceptable Adverse Effect Levels (UAELs).

The figures below present our noise levels in 2013 and 2035, showing these required details.

Aspects of our proposals that could cause effects

Construction may cause an increase in noise for those people living in homes closest to the areas being developed.

The figure below presents our noise levels in 2013 and our anticipated noise levels in 2035 showing these required details

The increased number of flights and the operation of a third runway will result in changes in noise from aircraft in the air and aircraft on the ground. Some communities will be newly exposed to aircraft noise. There may be changes in road and rail traffic noise associated with new or altered roads or railways associated with an expanded Heathrow.

Noise levels and definitions

Lowest Observed Adverse Effect Level (LOAEL)

The Lowest Observed Adverse Effect Level (LOAEL) is regarded as the point at which adverse effects begin to be seen on a community basis. As noise exposure increases above this level, so will the likelihood of experiencing an adverse effect. In line with this increase in risk, the proportion of the population likely to be significantly affected can be expected to grow as the noise level increases over the LOAEL.

Noise is likely to be noticeable and may be considered intrusive. Government policy requires such adverse effects to be mitigated and minimised in the context of policy on sustainable development. The impact of the Project depends on the change in noise caused, the resulting noise levels and the number of people affected.

Significant Observed Adverse Effect Level (SOAEL)

The Significant Observed Adverse Effect Level (SOAEL) is the level above which significant adverse effects on heath and quality of life can occur. As noise levels increase above SOAEL, they may become disruptive (e.g. avoiding certain activities during periods of intrusion; where there is no alternative ventilation, having to keep windows closed most of the time because of the noise; potential for sleep disturbance). Government policy requires significant adverse effects to be avoided in the context of policy on sustainable development.

Unacceptable Adverse Effect Level (UAEL)

The Unacceptable Adverse Effect Level (UAEL) is the level above which unacceptable adverse effects on heath and quality of life can occur. As noise levels increase above UAEL, they may become very disruptive (e.g. regular sleep deprivation/awakening). Government policy requires unacceptable adverse effects to be prevented from occurring.


The term “dB(A)” indicates that the decibel (dB) level is A-weighted to approximate the human ear’s sensitivity to sounds of different frequencies.


The term “Leq” is known as the equivalent sound level. It describes a person’s cumulative exposure to all sound occurring over a certain period (for example, a 16 hour day or an 8 hour night). It is the primary indicator used around the world by governments, researchers and non-government organisations such as the World Health Organization to describe community response to noise.

A summary of the effects reported in the Preliminary Environmental Information Report (PEIR)

During construction, noise will significantly affect some residents, schools and places of worship in areas closest to the new runway. This is due to the scale of construction and also the need for extended and 24-hour working in some locations. No significant effects have been identified relating to the increased (early growth) flights that are proposed before the third runway becomes operational (see Early Growth ). Whilst some noise changes will be noticeable during this period, these result from changes in airspace design that will happen with or without expansion. With early growth there would only be very small changes to the overall noise level given that the additional flights will be spread across the day.

An expanded Heathrow will result in changes in noise exposure that will influence health and quality of life – both positive and negative changes. The figure above presents forecast noise from an expanded Heathrow, based on one of our indicative airspace designs, using the Government’s thresholds for noise effect on health and quality of life set out earlier.

For some residents, the effects of Heathrow expansion will be positive and significant, with a large number of people experiencing a reduction in exposure to aircraft noise. These reductions are associated with mitigation such as the proposed 6.5 hour ban on scheduled night flights (see Night flights), displaced threshold landings on the existing runways and a package of measures to reduce the effects of night flights between 11pm and 7am.

For some other residents, even taking account of the mitigation proposed, the effects of Heathrow expansion will be negative and significant, with a large number of people experiencing increase in exposure to aircraft noise. For some, the third runway will mean that they have aircraft flying over them for the first time. With a third runway, and taking account of proposed noise mitigation measures, the PEIR reports that fewer residents would be exposed to noise levels in the daytime that are above the level where significant community annoyance begins compared to the 2013 baseline set by the Airports NPS. This reflects the aim of government noise policy to improve health and quality of life, where possible.

Significant effects from aircraft ground noise have been identified for some residents adjacent to the new runway and taxiways. There will also be significant effects from changes in road traffic noise for some residents, associated with new or altered roads linked to the expanded airport.

No significant effects of railway noise have been identified as part of the construction or operation of an expanded Heathrow.

Measures for reducing potential effects

Our approach to noise management has been developed to mitigate and minimise noise effects from construction, aircraft, road and rail, and then avoid any residual significant effects.

All airport construction activities will follow a Code of Construction Practice. This will include measures to reduce noise and the other environmental effects of construction. The Draft Code of Construction Practice document is available as part of this consultation and is discussed in the Construction section.

To reduce the effects of aircraft noise, we are proposing to introduce a 6.5 hour ban on scheduled night flights and are planning to rotate the use of our runways to offer predictable breaks from noise, also known as respite.

We are also designing noise screens around the airport to provide a barrier for communities nearby from aircraft ground noise and controls over where and when aircraft maintenance activities can take place.

We understand that even after applying best practice in design and introducing necessary mitigation measures, some local people will still be affected by noise. We have therefore developed a Noise Insulation Policy to compensate those most affected.

Mitigating and minimising adverse effect of noise

Mitigating and minimising adverse effect of noise on health and quality of life and the ICAO Balanced Approach

We have to select noise management controls in accordance with Government noise policy and in line with the “Balanced Approach to Aircraft Noise Management”, and international policy produced by ICAO (International Civil Aviation Organisation).

The goal of the Balanced Approach is to identify the noise-related measures that achieve maximum environmental benefit most cost-effectively, using objective and measurable criteria. The need to apply the Balanced Approach is a legal and policy requirement.

The key principles of noise policy and the Balanced Approach are that non-restrictive measures (such as incentivising the use of quieter aircraft and requiring aircraft to use quieter operating procedures) are applied first as far as reasonably practicable, then compensatory noise insulation is provided at homes and community buildings, before finally considering the introduction of any measures that restrict airline operations.

Noise objective

At the Airspace and Future Operations Consultation in January 2019 we presented our proposal for a noise objective that we intend to use as a guiding principle for future noise management. As part of our DCO application we will submit our proposal for a noise objective to the Secretary of State for consideration, as it is the Government’s responsibility to set noise objectives for airports.

The Secretary of State will set the objective and it will then be used to inform future decisions about managing operational noise at an expanded Heathrow.

Following the analysis of the feedback received, we have changed our proposed noise objective and aligned it with the requirements of the ICAO Balanced Approach.

Our updated noise objective

“To limit and, where possible, reduce the effects of noise on health and quality of life and deliver regular breaks from scheduled fl ights for our communities during the day and night. We need to do this whilst making sure the measures we put in place are in line with the ICAO Balanced Approach.”

Noise envelope

The noise envelope is a set of legally binding and enforceable limits and controls to manage noise in the future while allowing the airport to grow. It will provide certainty both now and in the future. It will be reviewed after an agreed period.

It will be designed to protect communities while enabling the airport to operate efficiently and allow it to grow within these limits. It will deliver real benefits that can be shared between communities, consumers, and businesses during each stage of growth.

This framework could include:

  • Noise management controls;
  • The rules we will put in place to use them (agreed through the DCO process and approved by the Secretary of State for Transport);
  • The ways their effectiveness will be measured and how Heathrow’s performance will be communicated;
  • How the rules and controls will be enforced and validated; and
  • The time period for review

The noise envelope will include:

  • Enforceable limits that will bound airspace change and Heathrow operations
  • Local priorities
  • The mechanisms for sharing future technological improvements between airport growth and reducing noise impact on communities.

The Airports NPS requires us to develop the noise envelope with local communities and other stakeholders, something we are doing with an independently chaired Noise Envelope Design Group. Following feedback on our Airport Expansion Consultation in 2018, the group is made up of a small number of technical experts representing the interests of communities, passengers, local authorities and airlines.

The noise envelope is part of our plans for Environmentally Managed Growth at Heathrow, where increases in aircraft and passengers are only permitted if they are within strict environmental limits.

Please also see our Noise Insulation Scheme page for more information relating to this topic.

Our overall proposals

In addition to the question on this page, we also want to know what you think about our overall proposals to manage the environmental effects of expansion and, in particular:

  • whether there are any other initiatives or proposals that we should consider to address the emissions from airport related traffic or airport operations;
  • our proposals to help health and well-being, in particular whether there are any proposals that you think we should consider to address the effect of the Project on the health and wellbeing of our colleagues, neighbours and passengers;
  • our noise insulation schemes;
  • what factors are most important as we develop our proposals for noise management, in particular our proposals for the design and implementation of a noise envelope;
  • our proposals for maximising new jobs and training, in particular, whether there are any other ways that we can maximise skills and training opportunities to benefit our local communities;
  • on our approach to addressing effects on the historic environment, including any particular proposals you would like us to consider.

To respond to our proposals please answer the overarching question on the Environmental Introduction page.

Have your say

Noise is one of the biggest concerns for communities living close to airports. We are proposing to introduce new and improved ways to manage noise at an expanded Heathrow such as introducing a 6.5 hour scheduled night flight ban, utilising runway alternation and developing a noise envelope.

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