The full list of exemptions under the Act is shown below for your information. Where information falls within the scope of an 'absolute exemption', a public authority is not obliged to communicate it to an applicant. Information falling within the scope of a 'qualified exemption' must be assessed to decide whether the public interest in maintaining the exemption outweighs the public interest in disclosing the information.
If you require more detail it can be found in the The College of Policing's Authorised Professional Practice for the Freedom of Information Act.
Absolute Exemptions
S.21 - Information accessible to applicants by other means
S.23 - Information dealing with security matters (as certified by a Minister of the Crown) supplied by or relating to named security organisations
S.32 - Court records etc
S.34 - Parliamentary privilege (as certified by the Speaker of the House or Clerk of the Parliaments)
S.40 - Personal information (where the applicant is the subject of the information)
S.41 - Information provided in confidence
S.44 - Prohibitions on disclosure (by any enactment, incompatibility with any community obligation or contempt of court)
Qualified Exemptions
Subject to the 'public interest' test
S.22 - Information intended for future publication
S.24 - National security (excluding matters covered by the absolute exemption at S.23)
S.26 - Defence
S.27 - International relations
S.28 - Relations within the UK
S.29 - The economy
S.30 - Investigations and proceedings conducted by public authorities
S.31 - Law enforcement
S.33 - Audit functions
S.35 - Formulation of government policy
S.36 - Prejudice to the effective conduct of public affairs (excluding matters covered under the absolute exemption within this section)
S.37 - Communications with the Queen
S.38 - Health and safety
S.39 - Environmental information
S.40 - Personal information (where the information concerns a third party)
S.42 - Legal professional privilege
S.43 - Commercial interests