What UKAS assessors look for on temperature, under ISO 15189:2022
A summary for lab quality managers. It isn't UKAS guidance: your assessor's view is the one that counts.
1. Know every unit
(ISO 15189:2022, 6.3 Facilities and environmental conditions; 6.6 Reagents and consumables)
- List every temperature-dependent unit: fridges, freezers, incubators, water baths, the rooms where analysers and reagents sit, and sample transport.
- Record each unit's acceptable range, taken from the manufacturer's instructions or the method.
- Give each unit a unique ID that matches its records and its sensor.
2. Record and review
(6.3)
- Monitor each unit at a defined frequency. Continuous monitoring covers nights and weekends.
- Keep the records retrievable for your retention period.
- Show that someone reviewed the records and signed them off, with the reviewer and the date.
3. Alarms and response
(6.3; 8.7 Nonconformities and corrective actions)
- Set alarm limits for each unit, and document who is alerted, including out of hours.
- Record every alarm: the time, who responded and what they did.
- Treat an excursion as a nonconformity. Assess its effect on samples and reagents, and record the corrective action.
- Test the alarms, and keep the test record.
4. Calibration and traceability
(6.5 Equipment calibration and metrological traceability)
- Calibrate the monitoring sensors with traceability to national standards. A UKAS ISO 17025 certificate shows this.
- Match each certificate to the sensor's serial number, and check that it's in date.
- Track due dates, and record what you did when a sensor was found out of tolerance.
5. Measurement uncertainty
(7.3.4; UKAS LAB 48)
- Know the uncertainty of each monitoring sensor. It's on the calibration certificate.
- Document your decision rule. For example, set the alarm inside the limit by the uncertainty, so a +8 °C limit alarms earlier. Our guide works through an example.
6. Walk-in rooms and large stores
- ISO 15189 doesn't name mapping. For a walk-in cold room, a mapping study is the usual evidence that the probe represents the whole space.
7. Blood storage
Have ready for the assessor:
- the unit list with its ranges;
- 12 months of records, with the review sign-offs;
- the alarm log and responses;
- the alarm tests;
- calibration certificates matched to the sensors;
- the decision rule.
Sources:
Want us to go through it with your records?
Book a free 20-minute compliance check: we look at your current records, alarms and calibration against this list and tell you what an inspector would ask about. Book a 20-minute check or call 0121 794 8092.
