The WHO Regional Office for Europe launched these updated Night noise guidelines for Europe. The guidelines provide ground-breaking evidence on how exposure to night noise can damage people's health, and recommends guideline levels to protect health.
The new limit is an annual average night exposure not exceeding 40 decibels (dB), corresponding to the sound from a quiet street in a residential area. Sleepers that are exposed to higher levels over the year can suffer mild health effects, such as sleep disturbance and insomnia. Long-term average exposure to levels above 55 dB, similar to the noise from a busy street, can trigger elevated blood pressure and heart attacks. One in five Europeans is regularly exposed to such noise levels. A summary of the findings is provided below. Click on the link to access the full document.
RECOMMENDATIONS FOR HEALTH PROTECTION
Based on the systematic review of evidence produced by epidemiological and experimental studies, the relationship between night noise exposure and health effects can be summarized as below. (Table) Below the level of 30 dB Lnight,outside, no effects on sleep are observed except for a slight increase in the frequency of body movements during sleep due to night noise. There is no sufficient evidence that the biological effects observed at the level below 40 dB Lnight,outside are harmful to health. However, adverse health effects are observed at the level above 40 dB L night,outside , such as self-reported sleep disturbance, environmental insomnia, and increased use of somnifacient drugs and sedatives.
Therefore, 40 dB Lnight,outside is equivalent to the lowest observed adverse effect level (LOAEL) for night noise. Above 55 dB the cardiovascular effects become the major public health concern, which are likely to be less dependent on the nature of the noise. Closer examination of the precise impact will be necessary in the range between 30 dB and 55 dB as much will depend on the detailed circumstances of each case.
For the primary prevention of subclinical adverse health effects related to night noise in the population, it is recommended that the population should not be exposed to night noise levels greater than 40 dB of L night,outside during the part of the night when most people are in bed. The LOAEL of night noise, 40 dB L night,outside, can be considered a health-based limit value of the night noise guidelines (NNG) necessary to protect the public, including most of the vulnerable groups such as children, the chronically ill and the elderly, from the adverse health effects of night noise.
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Average night noise level over a year
L night,outside
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Health effects observed in the population
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| Up to 30 dB |
Although individual sensitivities and circumstances may differ, it appears that up to this level no substantial biological effects are observed. L night,outside of 30 dB is equivalent to the no observed effect level (NOEL) for night noise.
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| 30 to 40 dB |
A number of effects on sleep are observed from this range: body movements, awakening, self-reported sleep disturbance, arousals. The intensity of the effect depends on the nature of the source and the number of events. Vulnerable groups (for example children, the chronically ill and the elderly) are more susceptible. However, even in the worst cases the effects seem modest. Lnight,outside of 40 dB is equivalent to the lowest observed adverse effect level (LOAEL) for night noise.
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| 40 to 55 dB |
Adverse health effects are observed among the
exposed population. Many people have to adapt their lives to cope with the noise at night. Vulnerable groups are more severely affected.
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| Above 55 dB |
The situation is considered increasingly dangerous for public health. Adverse health effects occur frequently, a sizeable proportion of the population is highly annoyed and sleep-disturbed. There is evidence that the risk of cardiovascular disease increases.
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