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Election Event Logging Common Data Format Specification



John P. Wack


This publication describes an election event logging common data format specification for devices used in U.S. elections such as optical scanners, election management systems, and polling place devices. The data logged generally contains information about the conduct of the election, such as when the polls open, when a voter starts a voting session or casts a ballot, or when administrators logon to the devices, etc. The publication contains a UML model of the relevant election logging data and an XML format derived from the UML model. It also contains background information regarding requirements for election event logging in the Election Assistance Commission’s Voluntary Voting System Guidelines Version 1.1. It is part of a series of planned common data format specifications for voting equipment.
Special Publication (NIST SP) - 1500-101
Report Number


Common data format, disposition, elections, event, logging, timestamp, voting, VVSG.


Wack, J. (2020), Election Event Logging Common Data Format Specification, Special Publication (NIST SP), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed July 20, 2024)


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Created April 9, 2020, Updated June 9, 2020