CAA view SCRATCOH as part of ATS licensing, according to HSE
'Several Articles within the ANO are concerned with the operator and crew’s responsibilities with regard to the fatigue of crew. ‘Civil Aviation Publications’ (CAP371 - The Avoidance of Fatigue in Aircrews; and CAP 670 ATS Safety Requirements) support these Articles. Operators are required to establish schemes for the regulation of flight times and not permit any person to fly as a member of crew if they have reason to believe that the person is suffering from, or is likely to suffer from fatigue as may endanger the safety of the aircraft or passengers. Air traffic controllers are prohibited from undertaking their duties if they know or suspect that they are suffering from or, are likely to suffer from, fatigue as may endanger the safety of any aircraft. CAA have informed HSE that they view the CAP as secondary legislation (similar to an HSC ACoP) and that CAA will not grant approval or a certificate unless operators’ schemes are compliant with the CAP'
http://www.hse.gov.uk/aboutus/meetin...1204/c132c.pdf