Common temperature mapping mistakes
Most failed studies fail before the loggers are placed — in the plan, the metadata or the calibration.
- Sizing the study to the loggers available instead of the space.
- Uncalibrated or out-of-date loggers, or calibration at a different range from the study.
- No unique sensor identifiers or location descriptions, so the data cannot be mapped back to the space.
- Sensors on surfaces, in airflow from a diffuser, or at ceiling height rather than product height.
- Sampling intervals too long to see door events and defrost cycles.
- Studies too short to include a weekend, a delivery day or a defrost.
- Temperature unit assumed from the values rather than confirmed.
- Timestamps in mixed time zones or with daylight-saving jumps, merged without checking.
- Deciding the hot/cold-spot criterion after seeing the data.
- A report that never says what the study could not show.
ValiTrac's pre-flight and data-quality stages exist to catch the metadata, unit and timestamp problems on this list before any statistic is computed — and to refuse to guess the unit.
Frequently asked questions
- What is the most common temperature mapping mistake?
- Deciding the sensor plan from the loggers on hand rather than from the space, followed closely by sensors placed at the wrong height or on surfaces.
- Can mapping data in Fahrenheit be analysed with Celsius limits?
- Only after explicit conversion with the unit confirmed from the logger export, never inferred from the magnitude of the values.
References
- [1]WHO Technical Supplement 8 to TRS 961 Annex 9: Temperature mapping of storage areas (2015)
General technical guidance written against the cited sources. It is not regulatory or legal advice and does not replace the applicable standard, guideline or a qualified reviewer's judgement.
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