Table 1 Minimal sensor requirement for measuring temperature and relative humidity

Units

Celsius degrees, t, ºC

percentage

Reference European norm

EN 15758

EN 16242

Sensor

Resistance thermometer

Capacitive electronic hygrometer

Calibration (ISO/IEC 17025)

Periodic maintenance calibration

Operating range temp

−20 ºC to 60 ºC

5–95%

−10 ºC to 50 ºC

Uncertainty

0.5 ºC, desirable 0.2 ºC

2%

Repeatability

0.1 ºC

1%

Resolution

0.1 ºC

1%

Sampling interval

1 h or less

–

Response time

 < 60 s

–

Stability

 ± 2 °C/year

 ≤ 2%/year