Glossary · Safe work, maintenance and competence
Simultaneous operations (SIMOPS)
Also known as: SIMOPS
In occupational safety, simultaneous operations (SIMOPS) are activities performed at the same time whose interactions can create additional hazards or control conflicts.
- Machine safety
- Risk assessment
- Maintenance
In one sentence
Simultaneous operations (SIMOPS) are parallel activities whose interactions can create new hazards or conflicting controls.
Example
While one crew maintains a locked-out palletizer, a second crew recommissions the adjacent conveyor; the conveyor test run could push pallets into the palletizer zone unless the two plans are coordinated.
How it applies
- Machine safety: Each activity may be safe on its own. SIMOPS risk arises from the combination: shared energy sources, overlapping zones, one crew’s test run entering another’s work area.
- Integrated systems: On integrated lines, interaction hazards and shared safety zones make SIMOPS common during commissioning and shutdowns. Map which isolations and stop circuits each activity relies on.
- Maintenance: Coordinate through the permit to work system, with a single point of control that sees all permits and lockouts in the area.
- Technical documentation: Shutdown plans should list planned parallel activities and the agreed separation measures.
Simultaneous operations vs. interaction hazard
An interaction hazard arises from interacting system elements by design. SIMOPS hazards arise from interacting work activities at a given time.