Activity Decomposition Standards

Quote: Turnaround Project Planning Primer - Defining Activities
Activities must be clearly defined, and should be measurable. This means anyone should be able to determine if a particular activity (as defined) is in progress, or completed.

Activities must be defined every time there is a break or change in work content, and/or by changes in the work crew. Activities that are overly broad in scope are difficult to estimate, schedule and measure/report progress against.

I also consider whether there is any value in breaking down any tasks that have durations spanning more than a reporting period (shifts in my case) - both for tighter critical path scheduling possibilities and for easier progress measurements. For example, in turnaround schedules, refractory and coke removal are often planned as one task (per equipment of course) but they are very difficult to measure progress against accurately. I prefer to see them broken down into sections (by bay, wall, etc.) so that instead of just one task (remove refractory), you might see four (remove refractory @ north wall, south wall, east wall, west wall).

Bernard Ertl
eTaskMaker project planning software

I’ve worked in capital project construction and also am a Primvera certified trainer. When I teach, I use a simple formula to describe to my students how to break down work.

If an activity has more than one noun, one active verb or one responsible party, then it should not be one activity. This will ensure that work is easier to measure. (rough-in MEPS (mechanical electrical plumbing sprinkers)is my greatest example of too much scope)When scope is too general, control of specific duration is too hard to acheive.
I also recommend that the location designation always be included in each scope description for the activity. This location designation can be larger or smaller to monitor real identifiable work.

I get a lot of pushback from my construction contractor clients when I recommend this, as they are afraid that they will have "too many" activities. The ones that insist on grouped activities usually spend more on the schedule to fragment the schedules during replanning-updating. There was an old television commercial that suggested preventative maintenance, their punch line was "pay me now or pay me later".