Sleep disturbance (noise related)

Scope

Sleep disturbance describes the way people are sleep disturbed by noise from the Schiphol airport, the Netherlands.

Description

Sleep disturbance relates to the number of people being sleep disturbed to some degree by being exposed to noise. Several effects of noise on sleep, varying in severity (and evidence burden), have been measured:

primary effects like difficulties falling asleep, awakenings, sleep stage changes and instantaneous arousal effects during the sleep (temporary increase in blood pressure,

heart rate, vasoconstriction, release of stress hormones in the blood, increased motility);

secondary or ‘after effects’ measured the next day: decrease of perceived sleep quality, increased fatigue and decrease in mood and performance;
long-term effects on well being: increased medication use, or chronic annoyance.

References

Van Kempen et al (2005), Selection and evaluation of exposure-effectrelationships for health impact assessment in the field of noise and health [1].

Definition

Using a model to assess noise related sleep disturbance

Necessary input: Number of people exposed to different dB levels from a certain source (eg road transport, air traffic, rail, etc) at night time, expressed in Lnight.

Necessary model: A model that estimates the number of people being sleep disturbed (mildly, moderately, or severely) by a certain noise source.

Example model: Relations derived by Miedema et al (ref). See under Formula.

Using a questionnaire to assess noise related sleep disturbance

Necessary input: A questionnaire assessing the level of noise annoyance in the exposed population. Questions in surveys differ. In order to obtain comparable disturbance measures the scales are translated into a scale from 0 to 100. Cut-off points to assess the percentage of highly sleep disturbed persons are used, [variable: Annoyance | analogue to the definitions of percentage (highly) annoyed persons].

(Further references not provided here now)

Using a laboratory study to assess noise related sleep disturbance

Not covered here

Causality

List of parents:

Noise exposure

List of daughters:

Data

None, should be based on noise exposure data

Formula

Miedema aircraft sleep disturbance relationships:

Valid for Lden between 45-75 dB(A)

% Mildly sleep disturbed = 4.465 – 0.411 * Lnight + 0.01395 * Lnight 2
% Moderately sleep disturbed = 13.714 – 0.807 * Lnight + 0.01555 * Lnight 2
% Severily sleep disturbed = 18.147 – 0.956 * Lnight + 0.01482 * Lnight 2

Unit

Noise: Lnight - The equivalent sound level over night-time (23.00 pm – 07.00 am).

Sleep disturbance: Percentage of people sleep disturbed to some degree

Result

Percentage of people sleep disturbed to some degree (mildly, moderately, severily).