How to test the melt blown cloth? What are the test items?
Meltblown cloth is the core material for the mask to filter germs. The medical mask has three layers, and the meltblown cloth is the middle layer, which has strong filtration, shielding and thermal insulation, and can play the role of sterilization and virus isolation. Therefore, melt blown cloth detection plays a vital role in controlling the quality of masks. So, what about melt blown cloth detection? What are the test items?
The test items of melt blown cloth include: particle filtration efficiency (PFE), bacterial filtration efficiency (BFE), longitudinal breaking strength, transverse breaking strength, longitudinal elongation at break, transverse elongation at break, air resistance, air permeability, deviation per unit area, appearance, width, microbial index, etc.
1. Filtration efficiency
Filtration efficiency is a key index for mask quality evaluation. This is also one of the important quality standards of melt blown cloth. Therefore, referring to relevant standards, the bacterial filtration efficiency of mask melt blown cloth shall not be less than 95%, and the oily particle filtration efficiency of particle filtration efficiency shall not be less than 90%.
2. Air resistance
The influence of air resistance on people’s breathing when wearing masks. Therefore, the air distribution resistance of mask meltblown determines the comfort when wearing mask. The recommended indexes are air resistance ≤ 350pa and expiratory resistance ≤ 250pa
Common test standards for masks:
GB / T 32610-2016 (technical specification for daily protective masks).
GB 2626-2019 (self-priming filter anti particulate respirator).
Gb19083-2010 (technical requirements for protective masks).
Yy0469-2011 (technical requirements for medical surgical masks).
EN 149-2001 + a1-2009 (EU requirements for protective masks).
En14683:2019 + AC: 2019 (EU medical mask requirements)