Total float, also known as total slack, is a critical concept in project schedule network analysis. It represents the amount of time a specific schedule activity can be delayed from its early start date without delaying the overall project finish date or violating a schedule constraint. It is calculated as the difference between the late finish and early finish dates (LF - EF) or the late start and early start dates (LS - ES). Activities on the critical path have zero total float, meaning any delay in these activities will directly delay the project's completion.

1. Project Management Institute. (2021). A Guide to the Project Management Body of Knowledge (PMBOK® Guide) – Seventh Edition. Project Management Institute

Inc. Glossary

p. 242. "Float (Slack). The amount of time a schedule activity can be delayed or extended from its early start date without delaying the project finish date or violating a schedule constraint."

2. Project Management Institute. (2017). A Guide to the Project Management Body of Knowledge (PMBOK® Guide) – Sixth Edition. Project Management Institute

Inc. Section 6.5.2.2

p. 210. "Total float is the amount of time that a schedule activity can be delayed or extended from its early start date without delaying the project finish date or violating a schedule constraint."

3. Vanhoucke

M. (2013). Project Management with Dynamic Scheduling: Baseline Scheduling

Risk Analysis and Project Control. Springer Berlin

Heidelberg. p. 23. https://doi.org/10.1007/978-3-642-40438-2. "The total float (TF) of an activity is the time span in which the completion of an activity may occur without delaying the total project."