Article 22 of the Belgian Constitution is nearly a copy of article 8 of the European Convention on Human Rights (ECHR). It has been introduced in the Belgian Constitution by the constitutional amendment of 31 January 1994.  The Constitutional Court has held consistently that the constitutional legislator has sought to make that article consistent with Article 8 of the ECHR, and that it should be interpreted in conformity with the jurisprudence of the European Court of Human Rights (ECtHR). In its judgment n° 50/2003, it referred to the ECtHR Judgment of 21 February 1990 in Powell and Rayner v. United Kingdom and to the Chamber Judgment of 2 October 2001 in Hatton v. United Kingdom.  The Constitutional Court held that when noise from aircraft is reaching intolerable levels, that nuisance undermines the rights conferred on residents in the vicinity of an airport by Article 22 of the Constitution. Although the right to the protection of a healthy environment is contained in Article 23 of the Constitution, it cannot be inferred from that fact, that Article 22 could not be invoked when noise could prejudice the respect for private and family life, guaranteed by that provision. The Constitutional Court in its judgment N° 51/2003 partially annulled a provision of the Decrees of the Walloon Region of 8 June 2001 and 25 October 2011 amending the Act of 18 July 1973 on noise abatement. That provision provided for a delimitation of noise-exposure zones around regional airports in function of the level of noise exposure from the operation of the airport. In the zone A the land owners had the right to sell their homes to the government, while those situated in the zone B were only entitled to a financial intervention for noise insulation measures.  The appellants  challenged the relevance of the 70 dB (A) maximum set for distinguishing zone A from zone B in the noise-exposure plan, given that specialist scientific studies described as unbearable any noise exceeding 66 dB (A) when "Ldn" was used as the indicator. The Court noted that none of the reports by the different experts established that residents living in that zone could occupy their houses without unreasonable disturbance to their private lives. Soundproofing could reduce the noise levels sufficiently to remove the danger to residents' health but they would still be unable to leave doors or windows open. Consequently, in the Court's view, residents in zone B, in terms of their right to respect for private and family life, were essentially in exactly the same predicament as those in zone A, with the result that the difference in treatment which the appellants had complained of could not reasonably be justified.