"According to the contract" is always correct nonsense. According to the basic principles of standard formulation and the basic principles of standardization, according to the contract is not what the standard should stipulate. So writing "according to the contract" and "provided by the supply and demand contract" is equivalent to saying nothing. Therefore, it is understandable that mask manufacturers, especially companies that switch to mask production due to the outbreak, are understandable when they read these standards.

Does "listing technical indicators" solve the problem? It is not necessarily, at least there are some issues that are worthy of discussion (take filtration efficiency as an example). One is that the filtration efficiency levels specified by the meltblown cloth(Melt Blown Fabric Factory) standards for these masks basically copy the requirements of some current mask standards for filtration efficiency, but the filtration efficiency of the mask is obtained by comprehensively considering the comprehensive performance of the mask and overall testing. Cloth filtration efficiency is not exactly the same thing. Excuse me, is KN95 grade meltblown cloth used for the production of KN95 masks or other? The second is to use KN30, KN60 or KN30-80 grade meltblown cloth materials, can we make qualified masks? Or how can we make qualified masks? Third, the pretreatment when testing the filtration efficiency of masks is an important step to indirectly assess the durability of filtration efficiency. Some masks with melt blown cloth standards basically do not require pretreatment for the test of filtration efficiency, which lacks the lasting filtration efficiency of melt blown cloth. The gatekeeper of sex. Fourth, there are many types of medical, industrial, and civilian masks. The functional requirements of protective masks and general masks are quite different. There are also differences in the filtration efficiency requirements and test conditions of different types of masks (see the table below). These masks(PP Meltblown Nonwoven Vendor) are currently used The meltblown cloth standard stipulates the grade of filtration efficiency, but still does not solve the problem of selection of different masks. Therefore, companies that switch to face masks still have not got a satisfactory answer.