What's the UoM for the Duration within the Events database?

Hello Canary team

What's the UoM (or business logic) behind the duration attribute of the Events table within the Events database? Below are examples of a 1 second duration, which would make the unit of measure to be 10^7, unless there is any business logic behind that. 

 1200000000 corresponds to 2 minutes. 

3000000000 to 5 minutes. 

Wondering how to interpret that value from a Canary System design perspective. 

Background of the question: defining GxP system requirements, which requires me to specify the UoM for that value, as it's considered an electronic record. 

Thanks