The constant temperature and humidity laboratory is to make the temperature and humidity of a laboratory meet the requirements of a standard atmosphere for humidity regulation and testing through some special equipment and technical methods. The constant temperature and humidity laboratory is the infrastructure for product quality inspection and control of production enterprises and commodity quality inspection and control in the circulation field. The constant temperature and humidity laboratory is widely used in cotton textile, wool textile, chemical fiber, paper, packaging, tobacco production enterprises, quality inspection, fiber inspection and other departments. According to relevant ISO and GB standards, the inspection of physical items of commodity quality such as textiles, textile raw materials, paper, paper products and cartons must be carried out under standard atmospheric conditions. In addition to the constant temperature and humidity laboratory with conventional temperature and humidity, there are other special constant temperature and humidity laboratories with special requirements such as 5-18 ℃ low temperature, 30-80 ℃ high temperature, relative humidity less than 40% RH low humidity, and relative humidity higher than 80% RH height.

Key points of overall design planning of constant temperature and humidity laboratory:
1. Temperature and humidity control range 2. Temperature and humidity control accuracy 3. Cleanliness requirements 4. Illumination requirements 5. Equipment heat and humidity range 6. Air conditioning supply and return air method 7. Air pressure balance measures
2. Necessity of introducing fresh air 9. Necessity of system exhaust 10. Measures for thermal insulation 11. Configuration of facilities and power 12. Static electricity, vibration, and noise 13. Equipment space and air conditioning room
3. Arrangement of access and changing buffer zones 15. Adequate maintenance space 16. Indoor net height and floor load 17. Pollution, pollution and disaster prevention 18. Measurement of installation and operation costs
4. Aesthetic requirements 20. Installation cost/schedule control 21. Operating cost 22. Maintenance and elasticity factors