There are various options available for one-off dust masks to cater to different operational needs and working conditions. The choice of mask should primarily depend on the concentration of dust and its toxicity. According to the guidelines specified in GB / T18664 "Selection, Use, and Maintenance of Respiratory Protective Articles," all dust masks, being semi-face masks, are suitable for occupational exposure limits of up to 10 times the concentration of hazardous substances. However, if the particles are highly toxic, carcinogenic, or radioactive, it is advisable to opt for a full face mask or a respirator with a higher level of protection. Similarly, when dealing with oily particulate matter, it is crucial to select the appropriate filter material. On the other hand, if the particles are needle-like fibers such as slag wool, asbestos, or glass fiber, dust masks are unsuitable since they cannot be washed, and persistent contact with the micro-fiber mask in the sealing parts of the face may cause irritation.