Understanding Security Levels

Government Protective Marking Scheme

There are effectively 4 levels of Government protective marking of documents.

OFFICIAL – The majority of Public Sector documents fall into this classification.

OFFICIAL SENSITIVE – OFFICIAL documents containing information that could have more damaging consequences, carrying an enhanced level of risk for which additional controls are required.

SECRET – Documents containing very sensitive information where compromise carries a high impact of risk to military capabilities, international relations or the investigation of serious organised crime.

TOP SECRET – Documents contain HMG’s most sensitive information requiring the highest where compromise could cause widespread loss of life or else threaten the security or economic wellbeing of the country or friendly nations.

According to CPNI all Secret and Top Secret documents should be destroyed to a minimum of P-5 security, and should not be disposed of using a shredding service.  In practice many Security Controllers will want to destroy Secret and Top Secret documents at P-6 or P-7.  Whilst no longer official guidelines, a sensible approach to the security levels and appropriate security levels for destruction is outlined below.

Government Protective Marking Scheme

There are effectively 4 levels of Government protective marking of documents.

OFFICIAL – The majority of Public Sector documents fall into this classification.

OFFICIAL SENSITIVE – OFFICIAL documents containing information that could have more damaging consequences, carrying an enhanced level of risk for which additional controls are required.

SECRET – Documents containing very sensitive information where compromise carries a high impact of risk to military capabilities, international relations or the investigation of serious organised crime.

TOP SECRET – Documents contain HMG’s most sensitive information requiring the highest where compromise could cause widespread loss of life or else threaten the security or economic wellbeing of the country or friendly nations.

According to CPNI all Secret and Top Secret documents should be destroyed to a minimum of P-5 security, and should not be disposed of using a shredding service.  In practice many Security Controllers will want to destroy Secret and Top Secret documents at P-6 or P-7.  Whilst no longer official guidelines, a sensible approach to the security levels and appropriate security levels for destruction is outlined below.