Routine maintenance runs on a steady crew. Construction builds up over months. A shutdown does neither: the workforce can multiply within a few days, work around the clock across every discipline, and then disappear almost as fast. That compressed profile makes shutdown manpower planning for multi-discipline work one of the most demanding parts of shutdown preparation. Here is how planners and maintenance managers build the numbers, structure the shifts and avoid the gaps that show up on day one.
What is shutdown manpower planning?
Shutdown manpower planning is the process of calculating how many people are needed in each trade and role, on each shift, for the duration of a planned shutdown, based on the frozen scope and schedule, and then arranging how they will be sourced, supervised and supported.
How shutdown manpower differs
| Aspect | Routine maintenance | Construction | Shutdown |
|---|---|---|---|
| Duration | Continuous | Months to years | Days to weeks |
| Ramp-up | Stable | Gradual | Very steep |
| Shifts | Mostly day shift | Mostly day shift | Often round the clock |
| Workforce mix | Core plant team | Construction trades | Core team plus large temporary workforce |
| Cost of a gap | Backlog grows | Schedule slips | Lost production every day |
Building the plan from work packs
- Man-hours by trade for every work pack, taken from the job steps.
- Load the hours into the schedule so each pack’s hours fall on the right days and shifts.
- Sum by trade, by shift, to see the true demand curve, which is usually spiky.
- Add support trades: scaffolders, insulators, riggers, crane operators and hydrojetting crews.
- Add supervision and control roles: shift superintendents, area coordinators, permit issuers, gas testers, safety observers, QC inspectors and planners.
- Add allowances for absence, fatigue relief and emergent work.
Converting man-hours into a chart is the same discipline described in how to build a multi-discipline manpower histogram, compressed into days rather than months.
Shift patterns and fatigue
Twelve-hour day and night shifts are common during turnarounds. They maximize working time but raise fatigue risk, especially across long stretches of consecutive days. Set limits on consecutive shifts, plan relief crews for longer shutdowns, and overlap shifts long enough for a proper handover. Night shifts usually need their own supervision and support, not a skeleton version of the day team.
Roles that are often under-planned
- Permit issuers and gas testers. Hundreds of permits a day can overwhelm a small permit team, and every waiting crew is lost time.
- Scaffolders. Most mechanical work needs access first, and scaffold demand peaks at the start.
- Hole watches and fire watches. Confined space entries and hot work each need dedicated attendants.
- QC inspectors. Inspection hold points stop work if inspectors are not available on the shift.
- Materials and tool crib staff. Crews waiting for parts or tools cannot work.
Pre-shutdown and post-shutdown work
Manpower is needed before and after the main window. Before shutdown, crews erect scaffolding where safe, stage materials and prepare equipment. After the main work, crews box up, reinstate insulation, clear scaffolding and demobilize. Planning only for the peak misses these phases. The overall scale also depends on whether the event is a short maintenance stop or a full turnaround, a distinction explained in shutdown vs turnaround: what is the difference?
Sourcing the workforce
Most shutdowns combine the plant’s own maintenance team, its regular contractors and a temporary workforce brought in for the peak. The routine crew structure that sits underneath is described in planning multi-trade workforces for petrochemical maintenance. Bringing the temporary workforce to site on time is covered in turnaround workforce mobilization planning.
Checking the plan before committing
Test the peak against area density, camp and transport capacity, induction capacity, supervisor coverage and tool availability. A plan that puts too many people in one unit at once lowers productivity and raises risk.
The numbers start from the scope, so a well-controlled shutdown scope development process makes manpower planning far more reliable. Apex Core Engineering plans and supplies shutdown crews through its workforce planning and skilled manpower supply services.
Frequently asked questions
How far ahead should shutdown manpower be planned?
As soon as the scope is frozen and work packs have man-hour estimates. Temporary workforce sourcing needs that lead time.
Why do shutdowns often run short of permit issuers?
Because permit volumes peak at the start of the shutdown, when many jobs begin at once, and permit staffing is usually planned for normal operations.
Should shutdown crews work 12-hour shifts?
It is common, but it needs fatigue controls: limits on consecutive shifts, relief planning and proper handovers.
Plan your shutdown workforce with Apex Core Engineering.