Good measurements require more than a number on a display. A valid result depends on the quantity being measured, the instrument, its range and uncertainty, probe placement, environmental conditions and the decisions that result from the reading.
What to record
- Measured quantity and unit: for example temperature in °C or °F, pressure in Pa or inH₂O, relative humidity in %RH or air velocity in m/s or ft/min.
- Measurement location: include the sampling point, mounting position, access condition and distance when relevant.
- Operating state: note whether equipment was on, off, unloaded, at steady state or changing load.
- Instrument details: model, probe type, verification or calibration status, range and stated accuracy.
- Comparison basis: baseline, specification, control value or independent reference used to interpret the finding.
Example: interpreting a humidity comparison
If two instruments read 48% RH and 52% RH in the same stable air, the measured difference is 4 percentage points of RH. It is not automatically a 4% relative error and does not prove either sensor is wrong. Compare both instruments’ specifications and measurement conditions before deciding whether further testing is necessary. These readings are illustrative, not field data.
Published measurement guides
- testo 160: How to Configure Temperature and Humidity Monitoring by Model
- testo 150-T1: How to Configure Temperature Monitoring and Alarms
- testo 150: How to Configure Temperature and Humidity Monitoring : Choose the correct testo 150 module
- testo 110 Contact Temperature Measurement: Probes and Steps
- testo 108-2 Food Temperature Guide: Probe Use & Cleaning
- Testo 108 Food Temperature Guide: Probes & Core Checks
- testo 106 Food Temperature Guide: Core Checks and Alarms
- testo 105 Food Temperature Guide: Probes and Best Practices
- testo 104 Food Temperature Guide: Use, Cleaning and Verification
- testo 103 Food Temperature Measurement: How to Check Core Temperature
- testo 164-H1: How to Configure Temperature and Humidity Monitoring : What hardware and software belong to
- testo 190-T1: How to Log Sterilization Cycles Step by Step
- testo 770-1: Electrical Measurement Setup and Safe Use : Why the 770-1 is not the
- testo 755-1: How to Measure Voltage and AC Current Safely
- testo 760-1: Safe Electrical Measurement Setup, Leads and CAT Ratings
- testo 830-T1 Infrared Temperature Measurement Guide: Setup and Accuracy
- testo 810 Infrared Temperature Measurement Guide: Range, Spot Size & Accuracy Tips
- Testo 606-1: How to Inspect Building Moisture and Interpret Readings
- How to Assess Condensation and Mould Risk with the testo 608-H1
- testo 625: How to Assess Condensation and Mould Risk : What the testo 625 measures—and what
- testo 174 H: How to Configure Temperature & Humidity Logging—Setup, Placement and Data Review
- testo 174-T: How to Configure and Interpret Temperature Logs
- Testo 270: How to Test Frying Oil Quality and Read TPM
- testo 890 Setup and Emissivity Guide: Lenses, Distance and Analysis
These guides explain methods; official product manuals and applicable technical standards govern the actual safe operation and acceptance criteria for a particular job.