Task	Fixed factor	Variable factor
1. Job assignment, pick up tools, gas up equipment	X
2. Travel time to job site		X
3. Work site organization, tools, traffic signs	X
4. Actual work operation climbing tree, cutting branches for a particular size tree and pruning class	X
5. Presence or absence of electric wires, traffic, buildings		X
6. Clean up of work site, chipping brush, cutting up wood for a particular pruning class or activity	X
7. Disposal of debris at dump site		X
8. Travel time back to crew headquarters		X