IEC 62820-1-1:2016 specifies the technical requirements for the composition, functions, performance, and test methods of general building intercom systems. This part is applicable to the general intercom systems for building entry in residential or commercial buildings. General building intercom systems have been classified into two grades: Grade 1 adopts lower requirements to cover door-entry-systems not used for relevant security applications while grade 2 adopts higher requirements for building intercom systems for security applications. Each grade may adopt different functional and performance requirements, test methods and normative references.