Tips to ensure a successful calibration and humidity measurement

• Separate the measurement area from ambient using a humidity calibrator that effectively isolates the DUT sensor from ambient effects like temperature and humidity.

• Don’t allow air leaks between the inside and outside of the calibrator’s chamber.

• Ensure that you insert your sensors properly so they are isolated from ambient temperature.

• Don’t allow condensation to form.

• Wait long enough for the humidity generator to become stable and uniform along with the DUT.

• Avoid using materials such as plastics, wood and foam that absorb and emit water vapor.

• Use materials like PTFE nonstick coating and stainless steel for making humidity measurements.

• Avoid exposing the DUT or calibrator to volatile chemicals. Materials like perfumes and cleaners can damage humidity sensors.

• Keep the calibrator’s humidity chamber clean.

• Use only distilled water in the calibrator.

• Keep the door on the calibrator’s humidity chamber at all times.

• Monitor the chamber temperature/humidity sensor for drift using an external check standard. A chilled mirror hygrometer is often used for this purpose.