Laboratory thermometers and hygrometers are frequently used because laboratories have relatively high requirements for the environment, whether it is temperature, humidity, light, ground stability, etc., there are certain requirements. Some laboratories even have requirements for dust particles in the air. Therefore, it is very necessary to use a suitable thermometer and hygrometer to check. So how to ensure the accuracy of the thermometer and hygrometer and choose the right thermometer and hygrometer?

There are many methods for laboratory humidity detection, the most common ones are dynamic method, static method, dew point method, dry-wet bulb method, and electronic sensor method. Therefore, there are many thermometers and hygrometers used for detection. Commonly used in laboratories are dry-wet bulb hygrometers, dew point hygrometers, hair hygrometers, coulomb hygrometers, electrochemical hygrometers, and optical hygrometers. After understanding the types and performance measurement methods of these thermometers and hygrometers, we can conduct targeted inspections.

When calibrating the thermometer and hygrometer, it needs to be done in a constant temperature and humidity chamber, and then the temperature and humidity of the test chamber are set, and the test is started from the lowest value of the thermometer and hygrometer, and multiple temperature measurement points are set, such as 0℃, 0%RH, 20℃, 20%RH, 40℃, 40%RH, etc. After these measurement points are set, the temperature and humidity need to be slowly increased in the test chamber. After the conditions meet a point, stabilize for a period of time, and then continue to rise to the next test point until the final test point peak is reached.

Through the above operations, a set of thermometer and hygrometer data can be measured, and professional measurement and testing institutions cannot complete it with a set of data. Basically, more than a dozen sets of data or even more are required. Therefore, for a small thermometer and hygrometer alone, the instrument calibration institution will spend most of the day, and the calibration cycle will take a long time. Only in this way can the data obtained ensure that the error value is more accurate, the thermometer and hygrometer calibration data is more credible, and the effect is better.

Therefore, when we are looking for a calibration agency, we must find a real measurement agency to avoid encountering some direct certification agencies, otherwise not only the data cannot be used as a reference, but also the loss will be borne if problems are found in the end. When choosing a thermometer and hygrometer for the first time, what aspects should be considered if you want to find a thermometer and hygrometer with better quality and more accuracy?

In fact, only three aspects are needed: measurement range and actual quality. The measurement range of the thermometer and hygrometer is not only a feedback on the accuracy, but also the more accurate the thermometer and hygrometer, the smaller the error value will be. The range of conventional indoor thermometers and hygrometers is basically -10℃-40℃ to 10%RH-90%RH. As for the actual quality, you can mainly look at the durability of the shell and whether it can withstand the test of extreme environments such as dryness, condensation, and high temperature, because thermometers and hygrometers are often used in some special environments.

In fact, the thermometer and hygrometer may not seem large, but for the calibration agency, the working time and workload of its instrument calibration are still very large, which is why a special calibration agency is needed for calibration.