What auditors actually ask for
A cold room fails an audit when nobody can show when the product was last measured, who measured it, and what they did if the result sat outside the limit. A wireless sensor does not write the corrective action. It does remove the excuse that the clipboard was in another building. Design the dashboard so each reading keeps a timestamp, a device identity, and a location name your QA team already uses on paper.
Air temperature on the wall is not product temperature in a crate. Many sites need both, and they are different questions. Air tells you the room plant is running. Product temperature tells you whether a batch is inside the limit your plan already set. Do not let one number stand in for the other in the report export.
Particlesensing has shipped industrial sensors since 2001, with 2.5 million units deployed and a 0.3% field failure rate across that base. Those figures describe manufacturing history. They are not a promise that a cold room will pass an inspection. Your HACCP plan still owns limits, holds, and who is allowed to release a batch.
Architecture that stays boring
Put one LoRaWAN gateway where the survey says the cold rooms can hear it. Do not pull new sensor cable through insulated panels if the radio path is clean. Nodes inside a metal room may need the antenna outside the panel or a gateway in the adjacent corridor. Survey before you buy a second gateway.
Join devices with OTAA. Paste the decoder once on ChirpStack or The Things Network so the application stores degrees Celsius, battery, and a frame counter. Clone that device profile when you add the next room. A private network server is fine if it accepts the same payload formatter.
Export on the interval your plan names. A reading every few minutes is rarely required for a closed cold room; it burns battery and fills the database. Spot checks with the needle probe are a separate workflow from a wall logger. Write both intervals down before you quote maintenance.
Stock trials start at 100 units. Branding — logo, packaging, manuals — starts at 500 units. Cold-room projects are often smaller than that OEM threshold. Quote the stock kit first, and move branding only when a distributor wants the name on the carton.
Product temperature versus room air
Use a food-contact needle probe when the question is the core of a product, a sauce, or a soft matrix. Confirm stainless grade, wash-down limits, and cleaning steps on the datasheet, then follow the site hygiene SOP between checks. The probe page owns that specification. This solution page only says when you need it.
Door contacts help when a warm corridor and a careless door explain a temperature rise. Leak rope belongs where wash-down water can reach the floor outside the cold room, not as a substitute for temperature. Mix those kits on one application if the gateway covers both rooms.
Probe health flags matter. A decode that says the probe is not ok should not be averaged into a compliance chart. Hold the batch record and replace the probe. Battery millivolts belong on the maintenance list, not in the HACCP limit column.
What to hand to operations
Commissioning pack: gateway location, device EUIs, room names, decoder version, and the first functional-test uplink from the factory record. Without the room name, a perfect Celsius value is an orphan. Without the decoder version, the next technician pastes an old profile and stores moisture fields in a temperature column.
Training is short if the dashboard speaks in the same units as the paper form. Degrees Celsius, local time, and a red row when the plan's limit is crossed. Do not invent a second limit in the IoT platform. Read the limit from the HACCP document.
Replacement sensors should keep the same device name in the asset register even if the DevEUI changes. Otherwise year-two trends look like a new room. Note the swap date next to the frame-counter reset.
Limits of this pattern
This is not a life-safety system and not a medical cold chain qualification. It does not alarm the fire brigade. It does not replace calibrated reference thermometers where your procedure still requires them. Use the wireless log as the frequent record and the reference instrument on the schedule your quality manual already has.
Regional radio plans in the standard quote are EU868 and US915. A cold store in another band needs that channel plan confirmed before the decoder and the hardware ship together. Destination-market documentation is a separate pack; ask for it on the quote rather than assuming a mark is on every carton.
What to log in a cold room
| Question | Kit role | Do not confuse with |
|---|---|---|
| Is the room plant running? | Air or room logger on the same application | Product core temperature |
| Is the product inside the plan limit? | Food-contact needle probe | A wall sensor in the doorway |
| Did someone leave the door open? | Door contact | A temperature alarm by itself |
| Is wash-down water on the floor? | Leak rope or spot probe outside the room | A temperature decoder |
Related pages
FAQ
Does LoRaWAN cold room monitoring replace our HACCP plan?
No. It timestamps temperature so the plan has records. Limits and corrective actions stay in the plan.
Should I measure air or product?
Measure the thing the plan names. Air and product are different. Many sites log both with different devices.
How long does the needle-probe battery last?
Up to about two years at the scheduled interval on the datasheet. Faster checks shorten that window.
Where is the decoder?
The PS-610 decoder page lists named fields. Byte offsets are in the file shipped with the kit.