Cold chain management is the set of controls that keep temperature-sensitive stock within its required range from the moment it is received until it leaves the building. In a warehouse, that means checking temperature at the dock, holding chilled and frozen stock in the right zone, picking by date, and keeping a record of who did each check and when. A WMS cannot keep a chiller cold. It can make sure the right batch goes out first, that a failed check stops the stock being picked, and that every step is on file when an auditor or customer asks for it.
What cold chain management means in a warehouse
Cold chain management is the control of temperature from receipt to despatch, so that each handover keeps stock inside its limit. The UN children’s agency UNICEF describes a cold chain as “a chain of precisely coordinated events in temperature-controlled environments”. Its examples are vaccines, but the principle is the same for chilled food and frozen goods. A chain is only as strong as its weakest handover, and in most warehouses that is the dock, not the fridge.
For food, the UK rule is specific. In England, food that can support the growth of harmful bacteria must be kept at 8°C or below, and the requirement applies to the temperature of the food itself, not the air in the room. Holding such food above 8°C is an offence under the same regulations, set out in regulation 32. Wales and Northern Ireland have their own rules, so check the position for each site you run.
Chilled and frozen: the two cold chains you run in a warehouse
The two cold chains in a warehouse are chilled and frozen. They are handled as separate disciplines because the rules, the stock and the checks are different. Chilled stock has a legal ceiling of 8°C for food that can support bacterial growth. Frozen stock has to stay frozen, held at the storage conditions printed on its label, and a frozen product that thaws cannot be refrozen and sold as if nothing happened.
Transport adds its own split. Refrigerated vehicles and storage units use powered refrigeration, which is the active side. Last-mile parcels usually depend on insulated packaging and coolant packs, which is the passive side. A warehouse rarely controls the parcel, but it does control the load that goes onto the vehicle.
The 8°C figure is a legal ceiling, not a target. Many operators run chilled rooms well below it so that a small drift does not become a breach. Set your own target from the product specification and your own risk assessment, not from the regulation alone.
The stages of the cold chain
The cold chain has four stages in a warehouse: receipt, storage, picking, and despatch and transport. Each one is a handover where temperature can slip, and each needs a check and a record. The table sets out what has to happen at each stage and what the WMS can hold on file.
| Stage | What has to happen | What the WMS records |
|---|---|---|
| Receipt | Check the vehicle and the load, confirm batch and best-before date | Batch, date and receipt checks, stamped with the time and the operative |
| Storage | Hold chilled and frozen stock in its own zone, with quarantine for failed stock | Location, stock status and hold reason, with who set it and when |
| Picking | Pick the oldest in-date stock, from the right pallet, in the right zone | Pick by date rule, with scan confirmation of product and batch |
| Despatch and transport | Load a clean, ready vehicle and keep the load within its limit | Despatch record tied to the customer and vehicle; the record stops at the back door |
The table reads across the stages, but the weak points usually sit at the handover between two of them. Most temperature failures are found at receipt, where a load has waited on a dock, or at despatch, where a trailer has been left open.
Receipt: where most problems start
Receipt is the highest-risk stage because goods arrive unannounced, get counted in a hurry, and sit on a dock before they are put away. A standard GS1 pallet label carries three barcodes: one for article and quantity, one for batch, and one for the pallet number. Clarus can read those barcodes in a single pass, so the batch and quantity are captured without re-keying. That matters at a chilled dock, where every minute the door is open is a minute of cold air lost.
Where a batch or best-before date is not on the label, the handheld can prompt the operative to find it. Mathew Buttar, who leads Clarus implementations and go-lives, describes this as making the scanner ask for the information the user has to look for. If the user cannot find it, the next step is a decision, not a guess. Damaged stock can be received separately as a damaged quantity and put on hold, so it goes no further than the dock.
Vehicle checks are a manual step, but they can be built into the flow. Mathew Buttar gave the example of a food 3PL that renamed its scanner prompts to ask whether a vehicle was clean, free of damage and free of pest ingress, and whether frozen goods had defrosted or chilled goods had run over temperature. The answers are stored against the receipt, so the check is on record rather than in someone’s head.
Storage: keep the zones apart and the holds clear
Chilled and frozen stock should sit in separate zones. Clarus supports temperature-controlled storage, so each zone can be kept apart within the warehouse. Stock is available by default once it is put away, so anything that must not be picked needs an explicit hold. Clarus can automate that. A manufacturer’s product that needed veterinary sign-off was set to go into a quarantine location on receipt, and the automation put it on hold as soon as it was put away. Nobody had to remember to do it.
A hold is only useful if the reason is clear. Each hold can carry a reason code, which records what the problem was, who set the hold and when. The same is true when it is released, so the file shows the whole life of the stock.
Picking: rotate by date, not by habit
Picking is where stock gets rotated, and where the rule matters most. In Clarus, FIFO uses the date the stock record was created, down to the millisecond. Expiry-based picking is handled separately, as first-expiry-first-out, which is one of the rotation rules that can be set per client or per product. That keeps the two ideas apart, so a rule labelled FIFO is never quietly doing the job of an expiry rule.
Batch and date control can be switched on at account level and overridden at product level. Once it is on, the handheld asks for the batch on the relevant tasks, and it warns the operative if the batch scanned is not the one expected. Products that do not need batch control do not show the screen at all. For more on expiry and best-before tracking, see the feature page.
Bulk storage makes date rotation harder. The oldest pallet is often at the back of a stack, and moving fifty pallets to reach it is not practical. Clarus has a switch function for that situation. The operative scans the pallet at the front, and the system checks that it is the same product, the same date and the same batch before accepting it. Mathew Buttar’s rule of thumb is simpler still: stock with sell-by dates should not be bulk-stacked, and it should be easy to reach one pallet at a time.
Despatch and transport: where the record stops
The WMS record normally ends at the back door. Mathew Buttar makes the point directly: a warehouse can get the load to the door in perfect condition, and what happens once it is on the truck and leaves is a different story. A warehouse can record that the load was checked and released. It cannot measure the air in the trailer for the rest of the journey. For that, you need a monitored vehicle and a record from the carrier, and the two records should be matched when there is a dispute.
Temperature monitoring and breaches: what Clarus does and does not do
Clarus does not have built-in temperature sensor mapping, and it does not show a live temperature against a stock location. Mathew Buttar has said that temperature mapping does not exist in the system, and that temperature control in Clarus is a manual process. Checks are entered as fields in the task, rather than read from a sensor. Anyone selling the software as a live temperature system would be overstating it.
What Clarus does do is turn each check into a record. Checks are added as generic fields, which can be text, whole numbers or yes or no toggles, and each entry is timestamped against the transaction it belongs to. If a temperature reading is taken by hand at the dock, it goes in as a number and stays there. If you already run a separate logging system, keep its data there, and record the outcome of any breach in Clarus against the affected stock.
When a breach is found, the sequence is short. Record the reading against the stock. Put the affected stock on hold with a reason. Stop it being allocated to any order. Decide what happens to it under your own food safety procedures, which the WMS supports but does not replace. Mathew Buttar’s view of the wider problem is blunt: the system can set out the steps, but food operations still depend on people following them. In his words, “There is not a warehouse in the world that does not have errors.” The job of the process is to make the errors easier to catch, not to pretend they cannot happen.
Audit trails, traceability and food safety requirements
An audit trail records who did what, when, to which stock, so a food business can show it kept the chain intact. Certification schemes such as BRCGS expect traceability records that a business can produce quickly. The Cold Chain Federation, the trade body for temperature-controlled logistics, represents the operators who need to show this.
Clarus holds the transactional record: receipts, holds, releases, picks and dispatches, each with a time and an operative. It also holds the checks that are added to those tasks. Mathew Buttar notes that because each check is timestamped against the transaction, it can be linked to the person who did it and the time they did it. That is the record an auditor asks for.
Recall is where the record earns its keep. Campeys of Selby, a food business that runs on Clarus, can run a product recall in under five minutes, and it has secured BRC Double-A accreditation. In a recall, the question is what went to which customer, on which vehicle, and what is still in the building. Clarus can answer the first two from the dispatch data, and the remaining stock can be put on hold from the stock list within seconds, so it cannot be allocated to another order.
What a WMS does in a temperature-controlled warehouse
A WMS does the jobs that depend on accurate data and a clear sequence. In a temperature-controlled warehouse, that means:
- Batch and best-before capture at receipt: stock arrives with its date and batch on the record, not in a notebook.
- Holds with reasons: failed stock is held, and the reason, the person and the time are kept with it.
- Rotation by rule: picking follows the FIFO or expiry rule set for the product, and the switch function handles bulk pallets.
- Traceability: every dispatch links to a customer and a vehicle, so a recall starts with a list, not a search.
It does not do everything. There are no built-in near-expiry pop-up alerts, so the local process must include checking dates. Temperature sensing belongs with the monitoring system, not the WMS. Being clear about that boundary is what stops a cold store from relying on a screen that cannot see the chiller. For a wider look at software for food and drink operators, see our guide to the best WMS for food and beverage.
The payoff is in the admin and the accuracy. JODA Freight, a refrigeration logistics business, reached 99% stock accuracy by year two, having run in the 90% to 97% range in year one. Stock takes went from weeks of work in Excel to a single day, and year-end counts take two to three days.
How do you maintain a cold chain?
You maintain a cold chain by setting a check at every handover, controlling who can release stock, and keeping records you can produce on request. Start with the stage that fails most often in your operation, usually receipt or the dock, and tighten that first.
- Set the limit for each product from its specification and the legal ceiling, not from habit.
- Check and record at receipt, including batch and best-before date, before stock goes to the dock.
- Store chilled and frozen stock in separate zones, with quarantine for anything that fails a check.
- Pick by date, using the FEFO or expiry rule, and keep sell-by stock on pallets you can reach.
- Hold any stock that fails, with a reason, a name and a time.
- Keep the trail, so a recall can be traced to customers and vehicles in minutes.
Speak to a warehouse expert
If you’re evaluating your options and want to see how a purpose-built WMS works in practice, Clarus is worth a conversation. We work with 3PLs and distributors across the UK to implement warehouse management software that fits the way you operate, not the other way around.
Get in touch with our team to talk through your requirements.