Define performance assurance level When defining the Operate phase performance standards, it is important to consider how the performance assurance task will be carried out in practice during the Operate phase and to apply it at the appropriate level in the Asset hierarchy. Appendix 3 details the minimum level of granularity at which • the performance standards, performance assurance tasks and acceptance criteria shall beset, and • the results shall be recorded. The following are some examples which are also shown in Figure 8. Performance standards and acceptance criteria are set at anything from a system and/or area to an individual maintainable item. Examples are • at system level o fire detection system o emergency escape lighting system EP 2009-9009 Restricted 19