-27 they posed to the community.27 Prison security is a complex issue which encompass several aspects, such as physical security (walls, grilles, bars, gates, CCTV) and procedural security (searches, controlled movement, alarms, communications, management of keys and categorisation). Physical and procedural security are crucial, but not sufficient in themselves. Recent standards provide that to be secure prisons must also respect the principle of dynamic security. STANDARDS IN FOCUS Rule 51.2 EPR establishes that ‘The security which is provided by physical barriers and other technical means shall be complemented by the dynamic security provided by an alert staff who know the prisoners under their control.’ The Mandela Rules acknowledge the concept of dynamic security under Rule 76(c) providing that training of prison staff must include notions of ‘security and safety, including the concept of dynamic security …’.28 Dynamic security is also explicitly referred to in several Recommendations and Handbooks. 29 The concept implies that the respect of human rights, positive and fair staff-prisoner relationships and purposeful activities are equally essential aspects of a secure prison. It is based on the assumption that security in practice also depends on ‘dynamic factors’, such as: • to what extent staff knows how to interact with prisoners and does so on a regular basis, • to what extent staff is aware of what is going on in the prison and can make sure that prisoners are kept active in a positive way. 27. A definition of the term ‘security’ can be found in the EPR, Rule 51.1. 28. See also PRI and ODIHR, ‘Guidance Document on the Nelson Mandela Rules: Implementing the United Nations Revised Standard Minimum Rules for the Treatment of Prisoners’ (2018) 41 [PRI and others, Guidance Document]. 29. E.g. CoE, CM, ‘Recommendation CM/Rec(2012)12 for the Committee of Ministers Concerning Foreign Prisoners’ (2012) § 31.1; CoE, European Committee On Crime Problems (CDPC), Handbook for Prison and Probation Services Regarding Radicalisation and Violent Extremism PC-CP (2016) 2 rev 4, 31; for more general information see also United Nations Office on Drugs and Crime (UNODC), ‘Handbook on Dynamic Security and Prison Intelligence’ (2015) 29; CoE, ‘Strengthening the Protection of the Rights of Sentenced Persons: Trainer’s Manual on Dynamic Security’ (2018). Monitoring Prison Violence