Based on the manufacturer’s public information, medical experts’ suggestions, and extensive media promotion, Hong Kong citizens generally require masks to be protected by the American Society for Testing and Materials (commonly known as ASTM). It is located at the first level under the F2100 standard and mainly requires designated bacterial filtration. Rate (commonly known as BFE) and particle filtration rate (commonly known as PFE) reach at least 95%; followed by the European standard EN14683, which maintains BFE at least 95% without a PFE standard.  In order to meet the requirements, manufacturers generally pay attention to whether the three aspects of mask machine, dust-free workshop and mask spray cloth can reach the predetermined benchmark. Among them, dust-free workshops generally use International Organization for Standardization (commonly known as ISO) No. 14644-1, which is at least ISO Class 8 as the standard for judging eligibility.