Glossary

The “Guide to the Calculation of Noise Abatement Ranges” (Anleitung zur Berechnung von Lärmschutzbereichen) is a calculation method with which the noise abatement ranges can be established in accordance with the law on the protection against aviation noise dated 01.06.2007 and the first implementing ordinance of the aviation noise act dated 2007. This calculation method is also used in the calculation of the aviation noise in the NORAH Study. Wherever AzB08 is mentioned, this refers to the current version from 2008.

This term is used by noise researchers to described the observation that people react differently to a change of noise exposure than it would be expected based on the noise level. For example, they will feel more disturbed after an increase of the noise than others who have been consistently exposed to the same noise. The disturbance perceived may even increase before the noise actually rises. In reverse, people may feel overproportionally relieved when the noise reduces.

Confounding occurs when a phenomenon depends on two or more conditions that are mutually influencing. If, for example, we want to investigate whether frequent tooth brushing prevents tooth decay in children, it would not be sufficient merely to examine the brushing behaviour and the dental status. This is because children who frequently brush their teeth are most likely actively encouraged to do so by their parents (few of them do it of their own accord). The same parents will probably allow their children fewer sweets. It could be that the healthier teeth are not due to frequent brushing but to a healthier diet. We can only find this out by examining both.

The Consortium for the NORAH Study is made up of the scientists conducting the study as a team.

The equivalent continuous sound level (in short: LpAeq) is a measure for the average noise exposure over a certain period in which frequency, duration and level of the individual sound events are taken into account. The LpAeq is the basis for the determination of noise protection zones pursuant to the aviation noise act – separated according to day (6 – 22 hrs) and night (22 – 6 hrs). The LpAeq is stated in decibels (dB).

Every scientific study investigating how something affects people needs control persons. These persons are not affected or affected only to a minor degree by this “something” – e.g. noise or certain diseases. This allows scientists to compare differently affected groups and measure the effects of their investigation subject on people.

The Data Acquisition System contains data on the airport, the takeoff and landing corridors, as well as the number of flight movements. The system also stores the “noise class” to which the respective aircraft type belongs.

The decibel – “dB” or “dB(A)” – is a measure of sound pressure level and thus of loudness. The decibel scale from 0 to 120 dB(A) reflects the range from the absolute threshold of hearing to the pain threshold. The scale is not linear. We perceive an increase of ten decibels as roughly a doubling of the loudness – in the lower and at the upper ends of the range.

Depression is a severe psychological problem in which affected persons suffer from sadness, lack of motivation and loss of interests. The acute phase of depression, i.e. the usually temporary occurrence of the disease, is called a depressive episode.

A digital terrain model contains the elevation data for the terrain at several points. These points are arranged in specified, regular grids, e.g. 10 x 10 or 50 x 50 metres.

An electrode is an electrically conductive object that, together with a counter-electrode, can conduct electrical currents in tissue located between the two electrodes into a meter. In sleep examinations, electrodes are stuck to the body to measure, e.g., wake-up reactions.

An electrode is an electrically conductive object that, together with a counter-electrode, can send electrical currents in the tissue between the two electrodes to a meter. In sleep examinations, electrodes are stuck to the body to measure, e.g., wake-up reactions.

Epidemiology is the study of the distribution of risk factors and diseases in populations. It contributes towards a better understanding of the cause of disease. Epidemiology develops measures to prevent disease or to prevent the spread of disease. It also helps to develop strategies for the treatment of diseases.

The results of noise impact studies such as NORAH can often be expressed in exposure-effect relationships. This means that the scientists quantify as accurately as possible at which traffic noise exposure the risk of a certain disease increases by how much.

This relationship describes the connection between the noise a person is exposed to (exposure), and a specific risk. In some cases, such relationships are linear, so that it can be said, e.g.: a noise increase of 10 dB increases the risk of heart attack by x percent.

The Frankfurt Aircraft Noise Indices developed by the Airport and Region Forum (ARF) calculate the aircraft noise exposure during the day and night in the area around Frankfurt Airport. They take into account the overall landing and take-off situation on the basis of the six busiest months for air traffic. The Frankfurt Aircraft Noise Indices are based on dose-effect relationships that were identified within the framework of studies in the Rhine-Main Region and at Cologne/Bonn Airport.

The heart rate describes how often the heart muscle contracts and relaxes within a minute. The blood pressure measurement devices used in the study indicate the blood pressure and the pulse. In healthy persons pulse and heart rate are identical.

A hypothesis is an assumption or a supposition. Empirical science consists largely in the examination of hypotheses. Scientists set up their research in such a way that they can test their hypotheses. As long as the hypotheses are not refuted by the research, for example by measurement values or survey data, the scientists continue working on the basis of the hypotheses.

Immissions include noise and other environmental effects on humans. Immissions control refers to the totality of attempts to limit immissions to a tolerable level in the long term for humans and the environment.

The long-term energy equivalent sound level (in short: LpAeq) is a measure for the average noise exposure over a certain period in which frequency, duration and level of the individual sound events are taken into account. The LpAeq is the basis for the determination of noise protection zones pursuant to the aviation noise act – separated according to day (6 a.m. – 10 p.m.) and night (10 p.m. – 6 a.m.). The LpAeq is stated in dB.

The loudness is more a matter of perception. Two tones with the same sound level but different frequency are often perceived as being differently loud. The measurement unit of loudness is the “phon” and the definition of phon is based on the subjective comparison of two sound events.

The physical value which best describes how strongly nocturnal aviation noise impacts on sleep is the maximum noise level. It shows to what extent the aircraft noise stands out from the existing background noises. The annoyance effect overall depends on the height and the frequency of occurring maximum noise levels.

The physical value which best describes how strongly nocturnal aircraft noise impacts on sleep is the maximum sound level of the overflight noise. The annoyance effect overall depends on the height and the frequency of occurring maximum sound levels.

Blood pressure is stated in mmHg. 1 mmHg is the pressure that a one-millimetre column of mercury exerts. "Hg" is the abbreviation for the chemical element mercury.

Noise is generally described as undesired sound.

Awareness that language is made up of different building blocks: sentences, words, syllables, sounds. Phonological awareness also means that a child can detach himself from the meaning of the word “cat” and recognize that it starts with the same letter as “cake”.

A polysomnographic investigation registers several physical measurement values during sleep, including the brain activity and eye movements, the heartbeat and the breathing rhythm. This information helps doctors, for example, to identify the causes of sleep disorders.

These are skills that are responsible for the acquisition of reading in children. They develop before the child actually begins learning to read. Precursor skills include, for example: žž

• žPhonological awareness: refers to an individual’s awareness of the phonological structure, or sound structure, of spoken words.
• Attention: the ability to concentrate sufficiently on a text. žž
• Linguistic short-term memory: the ability, for example, to remember at the end of a sentence how it started.

In everyday usage a “pseudonym” is a false name, artist’s name or code name. The pseudonym makes it impossible to trace statements back to the author personally.

The Federal Data Protection Act defines pseudonymization as “substituting a person’s name and other identifying characteristics with a label, in order to preclude identification of the data subject or to render such identification substantially difficult.” In other words: features that can identify the individual person – for example the name – are substituted with a code, for example a randomly selected number. All of the personal details have to be substituted so that it is not possible to identify a person.

The pulse pressure is the difference between the upper (systolic) and the lower (diastolic) blood pressure value.

Secondary data are data that were already available before the current research project because they were originally collected for other investigation purposes. The NORAH Study on Health Risks is based, among other things, on secondary data – in this case on pseudonymized patient data from health insurance companies – which already existed before the NORAH Study.

In the sensitivity analyses the scientists carried out calculations separately for various sub-groups and then compared whether the estimate values found for the context differ substantially. If, for example, the connection is stronger for men than for women, this suggests that their blood pressure reacts more sensitively to noise.

In statistics, we speak of a significant result when the effect is very unlikely (usually less than five percent) to be coincidental. Significance can be reviewed by statistical calculations.

In sleep labs scientists can measure and observe the course of a person’s sleep and when he changes from one sleep phase to another. Almost all of the investigations carried out in sleep labs use polysomnography.

Socioeconomic status is an artificial term that attempts to summarize an individual's economic and social position in society. In the NORAH Study the socioeconomic status was determined with the aid of the so-called “Scheuch-Winkler Index”. This is calculated from the three factors: net income, education and qualification and professional position.

Sound is generated by vibrations of
a sound source.

This term is used by physicists to describe an individual event in which sound is generated.

This shortened expression usually refers to the sound pressure level – the physical quantity that describes the strength of the sound waves.

The sound pressure level is stated in decibels “dB (A)” and is a measure for the loudness. The decibel scale from 0 to 120 dB (A) reflects the range from the absolute threshold of hearing to the pain threshold.

In simplied terms, statistics speak of a significant effect when it is very unlikely (usually less than five percent) to be a random effect. Statistical significance is determined by calculations.

In order that a scientific study actually investigates what it is supposed to investigate, careful planning is necessary. Scientists refer to this as study design. It includes, among other things, the method of data acquisition as well as the type and scope of the data.

Blood pressure is usually recorded with two values. The higher value is the so-called systolic blood pressure. This measures the pressure in the arteries when the heart muscle contracts and presses the blood out of the heart chambers. The systolic blood pressure is, therefore, the pumping performance of the heart. The diastolic blood pressure is the phase in which the heart muscle relaxes and the heart chambers fill up with blood.

Telemedicine allows the measurement of body functions, in certain cases also the support of diagnoses and therapies even when doctor and patient are spatially separated. In everyday clinical work it can be used, among other things, for the registration and transmission of vital data such as pulse, blood pressure, blood sugar or lung function. The information is transmitted by the Internet, telephone networks or satellites. In the Blood Pressure Study the scientists used telemedical sets consisting of an upper arm blood pressure measurement device with Bluetooth® function and a mobile phone. The measurement devices transmitted the blood pressure values to the mobile phone, which then sent them in encoded form via a protected data line directly from the house of the study participants to the database of the NORAH scientists.

A tender is a special procedure for generating competing offers from different bidders looking to obtain an award of business activity in works, supply, or service contracts. In a public tender, a state or a community or authority declares a certain need, and calls on potential providers to make an offer.

Traffic noise is the unwanted sound from cars, aircraft or trains.

When a sleeping person changes from a deep sleep into the lightest sleep phase, or wakes up completely, the sleep researchers of the German Aerospace Center (DLR) speak of a wake-up reaction. Even in a quiet environment, sleepers will experience such a wake-up reaction around 20 to 30 times a night. Usually they cannot remember this in the morning.