There are various methods for measuring dust concentration, each with its own technical principles and application practices.

The weight method is a classic dust concentration detection method. By collecting a certain volume of air sample, the dust particles are collected on the filter membrane, and then the weight of the dust on the filter membrane is weighed to calculate the dust concentration. This method is simple and easy to implement, but the operation is cumbersome, time-consuming, and susceptible to factors such as environmental humidity. It is usually used for laboratory analysis or offline monitoring.

The optical method uses the principles of light scattering and absorption to measure dust concentration. By measuring the degree of light scattering or absorption of dust particles through optical instruments, the dust concentration can be calculated. Optical methods have the advantages of non-destructive analysis and high accuracy, and are widely used in industrial fields, especially for online monitoring and portable devices.

The electrical method uses the electrical signal generated by the contact between dust particles and electrodes to measure dust concentration. Usually, a constant voltage is applied to the electrode. When dust particles come into contact with the electrode, the resistance or capacitance of the electrode changes, generating an electrical signal. The dust concentration can be calculated by measuring the change in electrical signal. This method has high sensitivity and fast response speed, but it may affect the measurement results in high humidity environments.

The β - ray absorption method uses the attenuation degree of β - rays passing through dust samples to measure concentration. By measuring the change in counting rate between the β - ray source and detector, the dust concentration can be accurately calculated. This method is sensitive to small particles and is less affected by environmental factors, making it suitable for high-precision measurements. However, the use of beta ray sources requires strict safety measures and regular replacement to ensure measurement accuracy.