The Machine That Blocked the Aisle
We installed a machine in the plant. The machine’s footprint (the space it took) was 2×3 m. We placed it tight (against the wall). On the floor, the operator couldn’t get to the side (the machine was against the wall). Maintenance couldn’t reach the back (no clearance). The aisle (for a fork truck) was blocked. The problem: we laid out the machine by the footprint (the machine’s size), not by the clearances (the space around it for operation and maintenance). We moved the machine (1 m off the wall, 1 m from the aisle). The operator and maintenance could reach. The mistake was ignoring the clearances.
Machine footprint layout includes the clearances (space around the machine). This article covers the planning.
The Footprint + Clearances
A machine’s footprint (the base) is the machine itself. But it needs clearances (space around it):
- Operation clearance: The operator’s space (to load/unload, to reach the HMI).
- Maintenance clearance: The space to service (open the panel, reach the FRL, replace the filter).
- Aisle clearance: The space for a fork truck (or a person) to pass.
Step 1: Operation Clearance (1 m)
The operator stands in front of the machine (to load the part, watch the cycle). Leave 1 m of clearance (operator space) in front. The operator doesn’t stand in the aisle. For a machine with a door (open it to load), leave the door’s swing space (the door opens into the clearance).
The layout rule: Leave 1 m clearance on the operator side (load/unload). Leave 0.5 m on the maintenance side (service). Keep the aisle (fork truck) clear. The machine that blocked the aisle had no clearance (tight against the wall and the aisle). Plan the clearances, not just the footprint.
Step 2: Maintenance Clearance (0.5 m)
The technician services the machine (replaces the FRL filter, opens the panel). Leave 0.5 m clearance on the service side. The panel door opens (into the clearance). The FRL is accessible (article 119). For a deep machine (1 m), the back needs clearance (to service the rear components). Don’t push the machine tight against the wall (the back is inaccessible).
Step 3: Aisle Clearance
Keep the aisle (fork truck, person) clear. The machine doesn’t block the aisle. Leave 1.5 m (for a fork truck) or 0.8 m (for a person). Mark the floor (the aisle is painted). The machine sits within its footprint (not in the aisle).
Step 4: Door Swing
The panel door (article 168) swings open. The door’s swing space is the clearance. Don’t put the door against a wall (it can’t open). Plan the door swing (into the clearance). For a double door, both doors open (more clearance).
| Clearance | Typical |
|---|---|
| Operator side (load/unload) | 1 m |
| Maintenance side (service) | 0.5 m |
| Aisle (fork truck) | 1.5 m |
| Aisle (person) | 0.8 m |
| Door swing | Door width + 0.2 m |
A Layout Checklist
- What is the machine footprint? (m?)
- Is the operator side clear? (1 m?)
- Is the maintenance side clear? (0.5 m?)
- Is the aisle clear? (Fork truck?)
- Does the panel door open? (Swing space?)
- Is the FRL accessible? (Article 119?)
- Is the e-stop accessible? (Article 98?)
- Is the floor marked? (Footprint? Aisle?)
- Does maintenance reach the back? (Service?)
- Does the operator load/unload? (Test?)
The Bottom Line
Machine footprint layout includes clearances. The machine that blocked the aisle had no clearance. Leave 1 m (operator), 0.5 m (maintenance), 1.5 m (aisle). Plan the door swing. The machine that worked well wasn’t the smallest footprint — it had the clearances.
