# Commission Decision of 16 June 2009 on criteria to be followed in order to decide when the performance of an organisation acting on behalf of a flag State can be considered an unacceptable threat to safety and the environment (notified under document number C(2009) 4398) (Text with EEA relevance) (2009/491/EC), Division 1.3: Number of detentions in relation to total number of inspections over a three-year period

Extent: E+W+S+N.I.

being
Ul = N · p + 0,5 + z · [N · p · (1 – p)]1/2
where
n number of detentions
Ul threshold low performance
N total number of inspections (minimum number = 60)
p fixed yardstick = 0,05
z statistical significance factor = 1,645

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Source: https://www.legislation.gov.uk/eudn/2009/491/annex/I/division/1/division/1.3 (the official version)
Page: https://openlegislation.uk/eu-decision-2009-491/annex-I/division-1/division-1.3
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.