Temperature data logger calibration: how often, to which standards, and how
A temperature data logger is a battery-powered recorder that samples and stores temperature over time for storage areas, transport, and process monitoring. In cold chain and GxP applications its records are audit evidence, so traceable multi-point calibration is required for the data to be defensible.
Also known as: temperature logger, electronic data logging monitor (EDLM), temperature recorder, cold chain logger, USB temperature logger
How often should a temperature data logger be calibrated?
Single-use EDLMs with sealed limited-life batteries are not designed to be recalibrated and are replaced instead; reusable loggers must carry a calibration valid within the current year before each mapping or qualification study per WHO guidance.
Where this number comes from
WHO Technical Supplement 8 to TRS 961 Annex 9 requires mapping loggers to hold a NIST-traceable 3-point calibration valid within the current year and states that calibration should be done annually for recalibratable loggers, which is the norm across GDP/GxP practice; non-regulated users sometimes stretch toward 24 months, and 6 months appears where tolerances are tight.
Calibration intervals are a risk-based decision for the instrument owner, not a fixed rule: guidance documents such as ILAC-G24 and OIML D 10 describe how to set and adjust them from usage, criticality and calibration history. Treat the interval above as a starting point for your own quality system, not a compliance requirement.
What shortens or lengthens the interval
- Regulated GxP or cold chain use, where annual calibration with a valid certificate is an audit expectation, versus non-regulated monitoring
- Required accuracy: WHO mapping work demands error of no more than plus or minus 0.5 C at each calibration point, leaving little drift budget
- Exposure to temperature extremes, condensation, or physical abuse during shipments
- As-found drift history across the fleet; consistent in-tolerance results can support interval extension under ILAC-G24 methods
- Battery condition and sensor type, since some sealed single-use loggers cannot be recalibrated at all
Standards relevant to temperature data logger calibration
Product standard covering the full recording system (sensor, recorder, data handling) from -80 to +85 C for cold chain applications
Companion standard specifying the periodic verification procedure against the class requirements of EN 12830
Methodology for adjusting intervals from as-found history where no regulatory interval applies
Standards are referenced by designation and title. For normative requirements, always work from the current edition of the standard itself.
How a temperature data logger is calibrated
A typical temperature data logger calibration, in an accredited lab or in-house, follows this outline. The exact points, tolerances and paperwork come from the applicable standard and your own procedure.
- Inspect the logger (battery state, housing, sensor condition) and download or clear existing data; verify firmware and clock settings.
- Place the logger, or its external sensor, in a stable temperature source such as a calibration bath, dry-block, or environmental chamber together with a traceable reference thermometer.
- Calibrate at three points bracketing the use range per WHO guidance: one point below the low end, one in the middle, and one above the high end of the monitored range.
- Soak at each setpoint until both logger and reference are stable, then log readings over a defined period and average them for comparison.
- Compare logger readings to the reference at each point; for WHO mapping use, the guaranteed error must be no more than plus or minus 0.5 C at each calibration point.
- Adjust or apply correction offsets if the logger supports it; otherwise disposition as pass or fail against the acceptance criterion.
- Record as-found and as-left data and issue a traceable calibration certificate, which must be retained as an audit document and included in mapping reports.
Reference equipment typically used
- Temperature calibration bath, dry-block calibrator, or stable environmental chamber
- Traceable reference thermometer (PRT with readout) covering the test range
- Data download and configuration software for the logger
- Ice point or fixed-point check reference (optional cross-check)
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Sources
- WHO Technical Report Series No. 961, Annex 9, Technical Supplement 8: Temperature mapping of storage areas, World Health Organization
Interval claim: loggers must have a NIST-traceable 3-point calibration valid within the current year and calibration should be done annually; also the plus or minus 0.5 C acceptance criterion, 3-point bracketing scheme, and note that sealed single-use EDLMs are not recalibrated
- EN 12830:2018, Temperature recorders for the transport, storage and distribution of temperature sensitive goods - Tests, performance, suitability, CEN
Product standard scope for cold chain temperature recorders (-80 to +85 C, full recording system) cited in standards
- BS EN 13486:2023, Temperature recorders and thermometers for measuring the ambient or internal temperature for the transport, storage and distribution of temperature sensitive goods - Periodic verification, BSI/CEN
Existence and scope of the periodic verification standard for temperature recorders referenced in standards and procedure
Cite this data
Gaugelog Calibration Interval Reference, v1.0 (July 2026). 68 instrument types, 236 verified sources. Licensed CC BY 4.0.
Download as CSV or JSON. Intervals are typical starting points, not compliance requirements; every row cites its sources.
The interval on this page is one row of the dataset. Browse all 68 types on the calibration interval reference.