From top: Dublin Airport; Protesters against the new North runway at Dublin Airport over noise issues last February
The Aircraft Noise (Dublin Airport) Regulation Bill – sponsored by Independents4Change TD Clare Daly – to deal with noise levels at Dublin Airport returns – following amendments in the Seanad – for debate in the Dáil.
Astrid Madsen writes:
Beyond hearing loss, noise is a pollutant that is linked to cardiovascular disease, sleep and cognitive impairments. And we don’t know how many people are at risk; the figure for Dublin alone is at least 20,000.
Noise is a stress inducer that triggers a fight-or-flight response in the body and if you live beside aircraft, road or rail, your body will process the harmful effects of noise even if you’re not conscious of it. The health risk is especially well documented during the sleep stages.
Says Owen Douglas, a professor who researches noise at UCD:
“The evidence suggests that children are among the most susceptible, leading to problems with reading, attention span, problem solving and memory. There is a clear physiological response. The safe decibel levels presented in the WHO report are beyond a reasonable doubt accurate.”
People living near airports should only be subject to a level of noise akin to a library environment (45dB) while those near roads can bear a bit more, the equivalent to the amount of noise your fridge might make (53dB).
That’s according to the World Health Organisation (WHO) Environmental Noise Guidelines for the European Region published late last year.
This low threshold may sound surprising but there is a big difference between someone living near a source of noise and someone walking past. The difference is repeated exposure to mechanical sounds, aircraft being the worst.
The WHO considers noise “a disease burden that is second in magnitude only to that from air pollution” and is appraising the health impact of a wide range of noise emitters, from wind turbines to seemingly innocuous sources such as mobile devices.
The representative health body for over 190 countries estimates 50% of the EU population lives in areas where noise is considered to have adverse health impacts; in Ireland, Fingal County Council’s figure for the Greater Dublin Area (GDA) is at 1% because the data is incomplete.
The local authority, as part of its final Noise Action Plan, provided a list of how many people (20,300) in the GDA were affected by average noise levels at or above 55dB, based on 2016 data compiled by a UK acoustics consultancy paid for by the Dublin Airport Authority.The 2016 Census figure for the GDA is 1.9 million people.
The difference between Fingal’s figures showing how many people are affected by noise levels of 55dB or more, and the WHO strong recommendation of using 45dB as the cut-off is equivalent to a doubling of noise levels.
The decibel scale is logarithmic and on average, according to the US’s Federation Aviation Administration, a person perceives a change in sound level of +10 dB as a doubling of loudness.
Owen Douglas cautions that average values may not reflect the true extent of exposure with evidence suggesting that maximum values, such as an aircraft revving up at 6am, might be a better way of measuring sleep disturbance and resulting negative health outcomes.
However he also flags that the current noise methodology might be exaggerating how many people are affected by noise, which is partly why the research community is moving to a more accurate data collection system known as CNOSSOS.
The health impact of noise is well documented, which is why the public consultation document for Fingal County Council’s Noise Action Plan (NAP) published in September stated it would:
“consider the implications of any relevant [WHO] publication in terms of policy provision”.
The WHO guidelines were published in October and Fingal’s final NAP, published in December, discarded the recommendations on the basis that “National and/or EU led policy guidance is required”.
When Clare Daly managed to introduce the WHO guidelines into legislation that is currently going through the Dáil to appoint a noise regulator as required under EU legislation, the Aircraft Noise Dublin Airport Regulation Bill 2018, Minister for Transport Ross said:
“It is at EU level that this change [to introduce WHO guidelines for noise] must be made to ensure a consistent approach to mitigating noise across member states. It would be inappropriate for Ireland to second-guess this work and pre-empt any decision at European level.”
Ms Daly’s amendments were reversed in the Seanad before the Easter break.
A spokesperson for the Department of Communications, Climate Action and the Environment, officially in charge of implementing the WHO guidelines, said:
“The recent WHO recommendations on noise levels are not directly applicable in Ireland.”
A spokesperson for the Environmental Protection Agency cautioned that these values from the WHO guidelines for airports “will be a very significant challenge for all the member states”.
The challenge lies in implementing noise reduction strategies that are affordable.
This is an issue that councillor Roderic O Gorman has been tackling for his constituents living beside the M50. “There’s not enough money available to put into mitigation measures,” he says.
Transport Infrastructure Ireland, the body that would be in charge of installing noise mitigation walls, can’t be compelled by Fingal County Council to build them.
Even though O Gorman says engagement with the TII has been “more positive in the past year” he doesn’t expect a walling system to be installed any time soon.
“The barriers would have to be really big,” he says. “The most immediate win will be to ensure the next time roads are resurfaced they will be covered in a rubberised material which will help absorb some of the noise.”
Residents of Laurel Lodge, near the M50, are eyeing solutions from other European cities. “They are looking at building a tunnel over the road to eliminate the noise and to create amenities for pitches and gardens. It’s an ambitious project,” adds O Gorman.
Dublin Airport planning conditions
The Dublin Airport Authority (DAA) broke ground on building its second runway in February of this year on the back of planning permission it secured a decade ago from An Bord Pleanála (ABP).
The planning appeals board at the time had rejected its inspector’s recommendation that planning permission not be granted on health grounds.
It is not uncommon for ABP to reject its inspector’s report findings, however the board did impose a number of conditions – some of which the DAA is still contesting.
The most contentious one is the restriction on the number of aircraft movements at night (11pm to 7am) to just 65 based on the scientific evidence of the health impact noise has, now further substantiated by the 2018 WHO guidelines.
The WHO guidelines indicate that the only recognised mitigation measure for sleep disturbance is to rearrange flight paths or close runways for night time operations. The DAA says that with the one runway they are currently operating around 100 night-time flights.
“Sleep disturbance is the most well documented health effect and the direct link between exposure to noise and adverse health effects is clear,” says UCD’s Owen Douglas.
Other planning conditions included an insulation scheme and a buyout offer for nearby residents. The noise contour map the DAA is using to determine whether or not someone is eligible is 63dB*, a benchmark commonly used by airports worldwide.
However it’s impossible to prevent noise from getting into a garden that’s subject to aircraft noise, says acoustic engineer Karl Searson. He says that with roads there is the option of using walling systems, but aircraft noise will make its way into a garden or patio area.
Technically you can insulate a house to seal it off in its entirety, but if you open the windows noise will still get in.
“Based on the body of research to date regarding the health effects of noise, technically no one should be living near an airport if the recommended WHO noise limits are regularly exceeded,” says UCD’s Owen Douglas.
Sheelagh Morris is a resident of St Margaret’s, the village closest to the second runway that’s under construction. She says that she has to close her windows at night to get some rest:
“In the summer it’s especially difficult to put up with the humidity. I feel like a prisoner in my own house.”
Even though it’s impossible to protect residents from noise if their windows are left open, the DAA is insulating more than three times the number of houses it was asked to under the second runway planning conditions (over 200 houses).
And even though the insulation scheme was extended to those affected by both the current runway and the one under construction, the buyout scheme was not extended to those living near the existing runway.
As a result 38 dwellings are eligible for the buyout. According to Fingal’s Noise Action Plan there are 600 dwellings currently affected by average noise levels of 60dB or more.
A spokesperson for the DAA says the insulation scheme, entirely free of charge to the residents that are within their 63db contour map, aims to reduce noise levels between 5dB and 10dB.
The insulation scheme does not target a final decibel range – to ensure a good’s night sleep with windows closed the aim should be to hit 40dB as strongly recommended by the 2018 WHO guidelines.
“Especially now that I’m getting older sleep is becoming a real problem,” says Sheelagh Morris. “Planes will wake me up in the middle of the night. Then at 6am it’s one aircraft after another. It messes with your head.”
Astrid Madsen s a freelance journalist with over 10 years’ experience reporting on the construction industry in Ireland.
*Part of the complexity of dealing with noise is the data; unless otherwise noted in the article the decibel unit is Lden referring to a commonly used decibel average for day, evening and night. In the case of the DAA’s noise map to determine eligibility for the insulation measures and the buy out they are using a slightly different parameter LAeq, 16-hour noise contour, instead of Lden.