Various kinds of temperature and humidity instruments are used. When selecting, consider the user's actual application environment and requirements, such as range, output and display, installation methods, sampling methods, gas types, materials and structures, control and monitoring requirements, and environmental hazards. In addition, factors such as cost-effectiveness and maintenance workload should also be considered:

1. Cost-effective: When using the temperature and humidity meter, you can't just consider the price is low, you should choose the price and performance. This includes price, life, maintenance, and calibration costs.

2. Rugged: Wear-resistant tester type hygrometer sensors and housings are to be considered for their ability to withstand condensation, drying, extreme temperatures, dust, chemicals, or other contamination.

3. Verification: The verification method and whether it is easy to consider, even if you do not need high-precision results. It will save you the workload of checking a convenient instrument on site and in situ.

4. Quality Reliability, Average Lifetime: When the quality is not good, you can start from the overall impression, examine the quality appraisal and factory standards, and examine the history, reputation, market share and application of the manufacturer. The brand-name products are better than the general products. Manufacturers' products are better than manufacturers, and consulting other users is also a good method.

5. Adaptability: When the use situation is not a single one, consider the adaptability of the instrument.

6. Replaceability: Hygrometers are generally expected to be used interchangeably or with other probes to fit your host.

7. Maintenance: Check the time required for regular cleaning, renewal, and replacement of hygrometers.

8. Standby: Spare parts are indispensable for most users, and it is inspected whether suppliers can provide spare parts as soon as possible.

9. After-sales service: Whether there is a guarantee, maintenance and service agreement.