When is aircraft noise from a military airfield unlawful, and what does moving into a noise zone change? Supreme Court Decision 2007Da74560 on the 'defect in installation or management' and the tolerable limit

Question

Article 5(1) of the State Compensation Act makes the State or a local government liable for damage caused by a defect in the installation or management of a public structure. Civil Act Article 750 makes an intentional or negligent unlawful actor liable, and Article 763 applies Article 396 on contributory negligence to tort damages. Where residents near an airport claim damage from aircraft noise, the questions are what counts as a 'defect in installation or management', how the limit of tolerable interference is set, how noise levels are proved, and what follows when the resident moved into the noise area.

Decision 2007Da74560 raises those questions in a claim by residents around Daegu airfield against the Republic of Korea. The court below had admitted an appraisal of the noise, had found the noise damage unlawful where the noise level was 85WECPNL or above, and had reduced damages for plaintiffs who moved in after 1 January 1989 on a basis akin to contributory negligence. The State appealed on all three points.

Material to check

The statutes are Civil Procedure Act Articles 202, 338 and 341, on free evaluation of evidence, the form of the oath ('I swear faithfully to appraise according to my conscience, and to accept the punishment for false appraisal if there is any falsehood') and the commissioning of appraisals to public institutions, schools and other bodies; Civil Act Article 396, under which the court takes the creditor's fault into account in fixing liability and amount for non-performance, Article 750 on unlawful acts, and Article 763, which applies Article 396 to tort damages; and Article 5(1) of the State Compensation Act, which provides that where damage is caused to another by a defect in the installation or management of roads, rivers or other public structures, the State or a local government shall compensate for it. The current text of Article 5 also provides for recourse against a person separately responsible and was wholly amended on 14 March 2008.

The decisions are Decision 2007Da74560 (25 November 2010), and the two it cites: Decision 2002Da14242 (12 March 2004), on the meaning of a defect under Article 5(1), on the Maehyang-ri shooting range exceeding the tolerable limit, and on exemption where a person moves into a danger area, and Decision 2003Da49566 (27 January 2005), on the meaning of a defect, the criteria for the tolerable limit, exemption and reduction where a person moves into a danger area, and on Gimpo Airport exceeding the tolerable limit.

Possible readings

On proof of noise, the decision reads the appraisal process this way: measuring aircraft noise must rest on the appraisal of a person with expert knowledge or experience, and because the noise has a wide and continuous effect it is practically impossible to evaluate it by measurement alone. The ordinary method is to select representative points, measure the noise over a period, compare the measured values with values predicted by an authorised program, and accept the predicted values as a reliable noise level for the area if they fall within an allowed margin of error. An appraisal submitted on that basis by an appraiser sworn in under statutory procedure or commissioned by the court cannot easily be rejected merely by pointing to the possibility of minor errors in measurement, unless the measurement or prediction contained a fairly serious error, or the other side submitted objective material undermining its reliability. Civil Procedure Act Articles 202, 338 and 341 frame that procedure.

On a resident's move into a danger area, Decision 2002Da14242 supplies the rule the decision states: where a person moves into and lives in an area exposed to pollution such as noise, knowing of the danger and tolerating its effects, and the harm is not to life or body but only mental suffering or disturbance of daily life and the interfering act has a high degree of public character, the wrongdoer's exemption should be recognized unless the harm actually suffered exceeds the degree of danger understood at the time of the approach, or the danger has specially increased afterwards, or there are like special circumstances. Where litigation over pollution noise has been brought or compensation paid, so that the area is shown to be an affected area and this is widely known, there is more room to accept exemption for those who move in later. But where, on all the circumstances including the route and motive of the move, the person cannot be said to have approached the danger knowingly, Decision 2003Da49566 holds that the matter should be considered, in equity on a footing akin to contributory negligence, as a ground for reducing the amount of damages under Civil Act Articles 396 and 763, because such persons often cannot know of the danger precisely.

On the defect itself, Decision 2003Da49566 states that a 'defect in installation or management' under Article 5(1) of the State Compensation Act means that a structure devoted to a public purpose lacks the safety it should have for its use, and that this includes not only physical or external flaws in the facility endangering its users but also the case where, in the public use of the structure, the state and degree of that use exceed a certain limit and inflict on third parties harm beyond the limit that society is expected to tolerate. The tolerable limit is set case by case, weighing the nature of the right or interest infringed and the degree of interference, the content and degree of the public character of the interfering act, the peculiarities of the local environment, the environmental standards secured by public regulation, and the availability and difficulty of measures to prevent or reduce the interference or to avoid the loss.

What the decisions held

Decision 2007Da74560 dismissed the appeal and ordered the State to bear the costs of appeal, with all Justices agreeing; the reporting Justice was Justice Park Si-hwan. It held on each of the three points below that the court below, Seoul High Court in its judgment of 4 October 2007 (2007Na4440), had applied the law correctly.

On the evidence, the decision held that the appraisal report in Gap No. 1, submitted by a qualified expert through the court's appraisal procedure, was properly admitted as evidence of the aircraft noise from Daegu airfield, and that the State's claim of a breach of the rules on evaluation of evidence failed. On the merits it held that the court below had rightly found, after weighing the content and degree of the noise damage, the public character of the airfield and of military aircraft operations, and the local character of an area that, unlike other domestic airports in non-urban districts, had gradually become residential and urbanised with a dense population since the airfield opened, that noise damage in the residents' areas at 85WECPNL or above exceeded the tolerable limit of ordinary social life and was unlawful. It also upheld the reduction: since there was no evidence that when the airfield was installed around October 1970 it was widely known that the surrounding area was exposed to aircraft noise, but complaints by residents around the Maehyang-ri shooting range and press reports from about July 1988 made noise damage around shooting ranges and airfields a social issue, it was proper to find that the area became widely known as continuously exposed to aircraft noise only from about 1989, and to reduce the damages of plaintiffs who moved in after 1 January 1989 in equity on a footing akin to contributory negligence.

Points left open

The decision fixes 85WECPNL as the unlawful level for the areas around Daegu airfield on the particular circumstances it lists, including the urbanisation of the area and the public character of the military flights. It does not state that 85WECPNL is a general threshold for every airport or every noise claim, and it leaves the tolerable limit to be decided case by case under the criteria it lists.

The decision also leaves open when a mover into a noise area is exempted altogether rather than merely having damages reduced. It sets out the conditions for exemption and the special weight of moving in after the affected character of the area is widely known, but on these facts it applied only the reduction, and it does not say how the two outcomes are divided in later cases, nor how the exemption or reduction is computed.

When to reconsider

We revisit this brief if a later decision sets a general noise threshold or departs from 85WECPNL, if a later decision states how exemption and reduction are divided for residents moving into a noise area, if the appraisal rules in Civil Procedure Act Articles 202, 338 or 341 or Article 5 of the State Compensation Act are amended, or if the judgment on further proceedings changes these points.

Statutes referred to

• 민사소송법 제202조, 제338조, 제341조
• 민법 제396조, 제750조, 제763조
• 국가배상법 제5조

Decisions referred to

• 대법원 2010. 11. 25. 선고 2007다74560 판결 · Decision ledger
• 대법원 2004. 3. 12. 선고 2002다14242 판결
• 대법원 2005. 1. 27. 선고 2003다49566 판결

Verification status

The texts read for this brief were read at the National Law Information Center on 24 October 2026. They comprise Decision 2007Da74560 in its published items, summaries, reasons and disposition, the current text of the articles it cites, and the published items and summaries of the two precedents it cites.