# The Air Navigation (Noise Certification) Order 1990, Paragraph 1


In this Part of this Schedule—
“the noise certification reference conditions” means conditions in which—
(i) atmospheric pressure at sea level is 1013.25 millibars;
(ii) ambient air temperature is 25°C; and
(iii) in respect of an aeroplane with two seats, a passenger shall be carried for the flying trials.

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Source: https://www.legislation.gov.uk/uksi/1990/1514/schedule/1/part/VII/paragraph/1 (the official version)
Page: https://openlegislation.uk/air-navigation-noise-certification-order-1990/schedule-1/part-VII/paragraph-1
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.