This post lists out various Non functional requirements .. The Non-Functional Requirements on an IT Project are listed below. They are Reliability, Availability, Maintainability, Safety, Security, Scalability and Usability. Business Analysts beware that non-compliance of Non functional requirements can lead to outright rejection of software by the client or project failure
Interesting Read : http://www.iai.uni-bonn.de/III/lehre/vorlesungen/SWT/RE05/slides/09_Non-functional%20Requirements.pdf