SiteIt's 9pm on a Thursday in November. The trailers are backed onto the doors. The induct team is feeding parcels as fast as they can. Then the sorter stops.
The HMI shows a drive fault on one of the main loop sections. Your engineer heads up the walkway. Behind them, parcels pile up on the induct belts, then on the floor. The first outbound trailer is due away at half ten.
The shift manager has two questions. How long? And what do we do with this lot in the meantime?
Both matter. Most sites only plan for the first.
Two jobs, two people
A stopped sorter needs two things at once. Someone to fix it, and someone to run the site around it.
Don't let them be the same person. If your engineer is also the one deciding where the parcels go, neither job gets done well. They'll be pulled off the fault every five minutes to answer a radio call.
So split it from the first minute. The engineer owns the fault. The shift manager owns the floor. They speak at set times, every 20 or 30 minutes, with a short update. Our post on keeping the line manager informed has a simple way to do it.
Find the fault fast
Sorter faults usually fall into a few groups. A jam at a merge or a divert. A photo-eye or barcode scanner that's lost its view. A drive or motor on a loop section. A comms fault between the sorter controller and the WCS. A tilt tray, cross belt or shoe that's broken and stopped the loop.
The first job is to tell which it is. Read the fault log before anyone resets it. Walk the loop. Look for the parcel that's in the wrong place. In our view, most sorter stops start with a parcel, not a part. Our guide to sorter jams and the real cause goes through how to tell.
If it's a drive or a controls fault and nobody on shift is confident with it, call for help early. A sorter is a lot of kit to learn at 9pm on a Thursday.
Run the floor without it
While the fault's found, the parcels still need to go somewhere. Here's what most sites can do.
Hold at induct. Stop feeding the sorter and stop tipping trailers. Parcels in a trailer are safer and tidier than parcels on the floor.
Prioritise by departure. Work out which outbound trailers leave first, and which routes have the tightest slots. Hand sort only for those.
Hand sort in a set area. Put roll cages out by route, in one marked zone, away from the sorter and its access gates. Keep forklifts and tuggers out of it.
Talk to the customers. If a trailer will miss its slot, tell the receiving site now, not at 11pm. Our post on late trailers and missed slots covers what a missed slot really costs.
Hand sorting is a manual handling job
This is the part that gets missed. A sorter takes the lifting out of the job. When it stops, people are picking parcels off the floor and throwing them into cages, for hours, on a shift they didn't plan for.
The Manual Handling Operations Regulations ask you to avoid risky manual handling where you reasonably can. Where you can't, you assess it and reduce the risk (regulation 4). HSE's guidance is clear that "the law does not set specific weight limits" (HSE, manual handling). So "they're only parcels" isn't an assessment.
Do the assessment once, on a quiet day, for your fallback plan. Think about how far people reach, how low they bend, how long the shift is, and the heavy parcels that turn up in every load. Then plan the layout to cut it down. Cages at waist height, tables to sort on, and rotation so nobody does three hours straight.
The same goes for the people you move. Pickers and loaders pulled onto hand sorting are doing a new job. The Management Regulations ask for training when people face new or increased risks from "being transferred or given a change of responsibilities" (regulation 13). Agency staff brought in for the night are owed information on any "special occupational qualifications or skills" the work needs (regulation 15). A two-minute brief at the start does it. Our post on duties to agency workers has more.
Keep the engineer safe while you push
When the floor is in chaos, the person up on the sorter gets forgotten.
A sorter fault often means work at height on a walkway, over moving conveyors, near the loop. Isolate the section you're working on. If the rest of the loop needs to run for testing, agree it with the engineer first, on the radio, every time. Nobody restarts a section without a word from the person on the walkway.
What the wait really costs
Here's our view. Most sites know what a sorter costs to buy. Very few know what it costs to stand.
Work it out. Add up the hand sorting labour, the overtime, the missed slots and any penalties in your contracts. Then add the cost to tomorrow's shift, which starts with tonight's backlog. Put that next to the cost of an engineer who knows your type of sorter, on call through peak.
For most sites, the sums aren't close. The sorter is a single point of failure, and you can't hold a second one. See single points of failure. What you can hold is a plan, and a number to ring. If peak is coming, our guide to getting engineering cover lined up for peak is the one to read this week.
What to do on Monday
- Write a one-page sorter-down plan: who owns the fault, who owns the floor, and where hand sorting happens.
- Do a manual handling assessment for hand sorting, and set out the area before you need it.
- Check who on each shift can fault-find the sorter's drives and controls, and who you'll call when nobody can.
- Work out what an hour of sorter downtime costs you in peak, and share it with your operations manager.