What are the test items for mask determination | Guidenonwoven.com

 Due to the impact of the epidemic, the demand for melt blown cloth remains high. However, so far, there have been a large number of unqualified melt blown cloths on the market. In order to facilitate enterprises to understand, we briefly summarize several major melt blown cloth testing items:

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1. Filtering power
The air extracted from the melt blown cloth detected by the particulate detector is equivalent to the air inhaled. The number of particulate matter measured in it represents the concentration of air particles after wearing a mask. Simply put, this concentration is the same as the environmental particulate matter outside the melt blown cloth. The ratio of the concentration is the leakage rate of the melt blown cloth.

As we all know, filter power is a key indicator for the quality of melt blown cloth. This is also one of the important quality specifications of melt blown cloth, so refer to relevant specifications, the filter power (dust resistance rate) of melt blown cloth, and the particle diameter of less than 5 microns must be greater than 95%. In the meantime, the value of 95% is not an average value, but a value, so the average value of actual products is mostly set above 99%.

2. Respiratory resistance
Respiratory resistance refers to the size of the influence that hinders breathing when people wear masks. Therefore, the breathing resistance of the mask meltblown cloth determines the breathing comfort when wearing the mask. It is advocated that the inhalation resistance should be ≤350Pa and the expiration resistance should be ≤250Pa.

3. Sanitary indicators
Hygiene index is naturally another important key index of mask melt blown cloth. Therefore, the items to be tested include: initial contaminating bacteria, total bacterial colonies, coliforms, pathogenic pyogenic bacteria, total fungal colonies, Escherichia coli, Staphylococcus aureus, Candida albicans, residues of ethylene oxide, etc.


Tips: The face of the mask has two sides, there will be several layers of folds on the face, and there is a hard strip on the side. When wearing, the hard side should be on top, because the hard strip can be used to pinch the bridge of the nose to ensure the tightness of the mask. Then the folds of the mask must be downward, because if the folds are upward, bacteria, viruses or dust will simply stay in the folds. Be sure to wear a mask correctly and do a good job of protection!