On May 6, 2020, the General Administration of Market Supervision (Standards Committee) formally released the recommended national standard GB/T 38880-2020 "Children's Mask Technical Specifications", which will be implemented immediately after it is released. The Code applies to masks worn by children 6 years old and above to 14 years old and below. The indicators in the "Code" are mainly based on the three aspects of protection performance, wearing comfort and safety, providing technical support and standard protection for children's mask manufacturers.
1. Protection effect:
The protective effect is a technical indicator for evaluating the protective ability of the mask against particulate matter during the wearing process. The protective effect was first introduced by the national standard GB/T 32610-2016 "Technical Specifications for Daily Protective Masks". In the "Code", the method is continue used to test the protective ability of the protective mask in the actual wearing process, and made three improvements. The first is to introduce five types of motions of still-shake-head-nod-speak-still-still to simulate the possible behaviors of children wearing masks, and investigate the impact of the above actions on the protective ability of the mask to ensure the comprehensiveness of the investigation. The second is to modify the respiratory frequency to 20 breaths/min, corresponding to a respiratory flow rate of 20 L/min, which is higher than the short-term breathing volume of children aged 6-9 years, and slightly higher than the short-term respiratory volume of children aged 9-12 years under moderate-intensity exercise conditions. The third is the size specification and classification of the test head mold according to the national standard GB/T 26160-2010 "Minor Head and Face Size" to ensure the representativeness of the test head mold. The improvements in these three aspects make the "Code" test for the protective effect of child protective masks more comprehensive and scientific. The standard stipulates that the protective effect of child protective masks should be ≥90%, which is consistent with the leakage rate requirements of KN95 grade masks in the national standard GB 2626-2006, which ensures the effective protective ability of the masks.
The "Code" requires that the bacterial filtration efficiency of children's sanitary masks be ≥95%, and that the residual amount of ethylene oxide should not exceed 10μg/g. This index is also the index adopted by the EU standard EN14683 and the American standard ASTM F2100. The index of bacterial filtration efficiency in the children's sanitary masks is the same as that of medical masks.
2. Comfort effect:
The comfort requirement (breathing resistance) is the main index for examining the obstruction effect of the mask on the user's breathing process.The standard stipulates that the resistance of children's masks shall be tested at 45L/min, and the inhalation resistance should not be greater than 45Pa to ensure the safety of younger children.
3. Physical performance indicators:
Considering the characteristics of children's behavior, the "Code" has added a number of physical performance indicators compared to the adult mask standard. For example, the respirator valve on the mask should not fall off during use, the mask band should not use a lace-up type. There is no obvious feeling of pressure and tenderness during wearing, and the impact on the head activity is small. At the same time, it stipulates that the nose clip should be made of plastic material, the length is ≥5.5cm, and the nose clip has certain requirements such as folding resistance. The Code fully considers the influence of children's behavioral characteristics on the safety of wearing masks. "Code" also fully considers the situation of children's own weak awareness of danger, gives relevant warning content, and requires that manufacturers must clearly mark.
4. Specifications and models:
According to the developmental characteristics of children at different ages, the Code divides children's masks into three models: large, medium and small, which can meet the children's needs for mask sizes at different ages. Under the premise of safety and protection, parents can choose the most suitable mask for their children.
