Non woven mask description |
| Release：2021/8/13 source： author： browse：706次 |
There are two kinds of non-woven masks. One is that the surface is made of pure cotton absorbent gauze or knitted fabric, and various non-woven fabrics are sandwiched in the middle; The other is sewn directly from non-woven fabrics. It has good filtering effect and poor air permeability. The latest variety is non-woven material on the surface and back, and filter paper in the middle, so as to make the filtering effect of non-woven mask to a higher level. The relevant documents on the technical requirements of medical protective masks were issued by the General Administration of quality supervision, inspection and Quarantine on April 29, 2003 and implemented on that day.
essential information
Non woven mask
Foreign name: non woven mask
Material non-woven fabric
Purpose filtering
catalogue
1. Structure composition
2 selection principle
3 no cleaning
4 Preface
5 specific contents
6 selection
7 mask type
Structural composition
Non woven masks are the most widely used category in our daily work. The structure of a non-woven mask should be divided into two parts. One is the main body of the mask, which can be simply understood as a mask frame; The other is the filter material part, including filter cotton for dust prevention and chemical filter box for anti-virus. Therefore, for the selection and use of filter masks, some products produced by Guangjia provide you with the following convenience, that is, you can use the same mask body. When you need to prevent dust in a dusty working environment, you can wear a dust mask with the corresponding filter cotton; When you need to carry out anti-virus in a toxic environment, replace the filter cotton and install the corresponding chemical filter box, so that it becomes an anti-virus mask again, or provide you with more combinations according to your work needs.
Selection principle
Dust blocking efficiency
The dust blocking efficiency of non-woven mask is based on its blocking efficiency against fine dust, especially respiratory dust below 5 microns. Because the dust of this particle size can directly enter the alveoli, it has the greatest impact on human health. The dust blocking principle of a general gauze mask is mechanical filtration, that is, when the dust collides with the gauze, some large particles of dust are blocked in the sand cloth through - layers of barrier. However, some fine dust, especially dust less than 5 microns, will pass through the mesh of gauze and enter the respiratory system. At present, there are some dust masks abroad. The filter material is composed of fibers filled with permanent static electricity. In the process of passing through this filter material, those respiratory dust less than 5 microns are attracted by static electricity and adsorbed on the filter material to capture fine dust, which really plays a role in dust prevention.
Degree of tightness
Air is like water flow. It flows where the resistance is small. When the shape of the non-woven mask is not close to the human face, the dangerous objects in the air will leak from the non-woven mask and enter the human respiratory tract. Well, even if you choose a mask with the best filter material. Nor can it protect your health. Many foreign regulations and standards stipulate that workers should regularly carry out the tightness test of non-woven masks. The purpose is to ensure that workers choose appropriate non-woven masks and wear masks according to correct steps.
Comfortable to wear
It requires small respiratory resistance, light weight, hygienic wearing and convenient maintenance. In this way, workers will be willing to wear them in the workplace and improve their work efficiency. The maintenance free masks in foreign countries do not need to be cleaned or replaced. They are discarded when the dust barrier is saturated or the masks are damaged, which not only ensures the hygiene of non-woven masks, but also eliminates the time and energy for workers to maintain masks. Moreover, many masks adopt arch shape, which can not only ensure good tightness with the shape of the face, but also reserve a certain space at the non-woven mask, which is comfortable to wear.
Unsuitable population
People with heart or respiratory difficulties (such as asthma and emphysema), pregnant women, dizziness after wearing, dyspnea and skin sensitivity, etc
No cleaning
The outer layer of the non-woven mask often accumulates a lot of dirt such as dust and bacteria in the external air, while the inner layer blocks the exhaled bacteria and saliva. Therefore, the two sides cannot be used alternately, otherwise the dirt contaminated by the outer layer will be inhaled into the human body when it is directly close to the face and become a source of infection. When the mask is not worn, it shall be folded and put into a clean envelope, and the side close to the mouth and nose shall be folded inward. It shall not be stuffed into the pocket or hung around the neck.
If the non-woven mask is wetted by exhaled heat or saliva, its function of blocking bacteria will be greatly reduced. Therefore, it is best to prepare more masks for replacement and wash them once a day. Wash with boiling water for 5 minutes.
Non woven masks should be cleaned and disinfected every day. Both gauze masks and air filter masks can be disinfected by heating. The specific measures are:
1. Cleaning. First gently rub the gauze mask with warm water and soap. The bowl mask can be gently brushed with a soft brush dipped in detergent, and then washed with clean water. Please note that do not rub hard, because if the warp and weft gap of the gauze is too large, it will lose the function of preventing droplets.
2. Disinfection. Soak the cleaned mask in 2% Peracetic Acid Solution for 30 minutes, or boil it in boiling water for 20 minutes, or steam it in a steamer for 15 minutes, and then dry it for standby. This method is suitable for gauze masks and bowl masks.
3. Inspection. Before reuse, carefully check whether the mask and mask are still intact. For gauze masks and masks, the light transmission inspection method can be adopted, that is, take care of them in front of the lamp to see if there are obvious light spots and whether the light transmittance of the middle part and the edge part are consistent. If there is any doubt, they should be replaced. In any case, masks and masks are generally updated after cleaning 3 to 7 times. Masks with particularly good quality can be cleaned 10 times. The activated carbon adsorption mask shall be replaced regularly. If the activated carbon interlayer is not replaceable, it shall be replaced after 7 to 14 days. This mask cannot be reused after cleaning.
concrete content
Range
This standard specifies the basic requirements, test methods, identification, operation instructions, packaging, transportation and storage of medical protective masks (hereinafter referred to as masks).
This standard is applicable to self-priming filtering dust-proof medical protective masks that can filter particles in the air and block droplets, blood, body fluids, secretions, etc.
Nouns and terms
3.1 filtering efficiency
The percentage of particulate matter in the air filtered by protective articles under specified conditions.
3.2 flame retardation
The performance of protective articles to prevent itself from being ignited, flaming and smoldering.
3.3 disinfection
Kill or remove pathogenic microorganisms on the transmission media by physical or chemical methods to make them harmless.
3.4 sterilization
Kill all microorganisms on the transmission medium by physical or chemical methods to make it sterile.
3.5 self absorption filter type dust mask
The utility model relates to a clean air breathing protector which overcomes the resistance of parts by the wearer's breathing and is used for dust prevention.
3.6 sealing half mask
A mask that fits closely with the face and can cover the nose and mouth.
3.7 spray rate
Indicates the degree of moisture resistance of the fabric surface.
technical requirement
4.1 basic dimensions of mask
a) Size of the center part of the rectangular mask after unfolding: the length is not less than 17cm and the width is not less than 17cm;
b) Size of closed arch mask: the transverse diameter shall not be less than 14cm, and the longitudinal diameter shall not be less than 14cm.
4.2 appearance
c) The mask surface shall be free of holes and stains;
d) The respirator shall not have an exhalation valve.
4.3 nose clip
a) The mask must be equipped with nose clip;
b) The nose clip is made of bendable plastic material with a length of no less than 8.5cm.
4. Mask belt
a) The mask belt shall be easy to adjust.
b) The position of the mask shall be fixed with sufficient strength. The breaking strength of the connection point between each mask belt and the mask body shall not be less than 10N.
4.5 filtration efficiency
The particle filtration efficiency of mask filter material shall not be less than 95%.
4.6 airflow resistance
When the gas flow is 85L / min, the suction resistance of the mask shall not exceed 343.2pa (35mmh2o).
4.7 penetration barrier performance of synthetic blood
Synthetic blood shall be sprayed into the mask sample at the pressure of 10.7kpa (80 mmHg), and there shall be no penetration on the inner side of the mask.
4.8 surface moisture resistance
The water contamination level of respirator shall not be lower than Gb3 in GB / t4745.
4.9 disinfection and sterilization
a) Masks marked as disinfection grade shall meet the requirements of 4.3.2 in GB 15980.
b) Masks marked as sterilization grade shall meet the requirements of 4.3.2 in GB 15980.
4.10 ethylene oxide residue
For masks sterilized with ethylene oxide, the residual amount of ethylene oxide shall not exceed 10% μ g/g。
4.11 flame retardancy
The materials used shall not be flammable. After moving away from the flame, the continuous combustion shall not exceed 5S.
4.12 skin irritation
The mask material shall be free from skin irritation.
4.13 signs and instructions
It shall comply with the provisions in 6 of this standard.
test method
5.1 basic size of mask
The measurement with general measuring tools shall comply with the provisions of Article 4.1.
5.2 appearance
Visual inspection shall comply with the provisions of Article 4.2.
5.3 nose clip
Through inspection and measurement with general or special measuring tools, it shall comply with the provisions of article 4.3.
5.4 mask belt
A total of 4 masks should be tested. 2 are temperature pretreated and 2 are not pretreated.
Temperature pretreatment conditions:
a) (70 ± 3) ℃ in air for 24 hours
b) (- 30 ± 3) ℃ in air for 24 hours
After temperature pretreatment, it shall be restored at room temperature for at least 4 hours.
Through visual inspection and tension meter measurement, it shall comply with the provisions of 4.4.
5. Filtration efficiency and air flow resistance test
6 mask filter materials shall be used for filtration efficiency test. Three are temperature pretreated and three are not pretreated.
Temperature pretreatment conditions:
a) (70 ± 3) ℃ in air for 24 hours
b) (- 30 ± 3) ℃ in air for 24 hours
After temperature pretreatment, it shall be restored at room temperature for at least 4 hours.
The air flow shall be stabilized to (85 ± 2) l / min.
The test shall be carried out until the filter material reaches the minimum filtration efficiency or at least (200 ± 5) mg aerosol acts on the filter material.
The particle size distribution of NaCl aerosol used under the specified test conditions shall be (0.075 ± 0.020) in the median diameter of counting μ m. The geometric standard deviation shall not exceed 1.86.
The measurement results of filtration efficiency shall be greater than or equal to the provisions of 4.5.
The suction resistance of the mask shall comply with the provisions of article 4.6 of this standard.
5.6 penetration barrier performance of synthetic blood
Check 5 masks.
The mask shall be pretreated at (21 ± 5) ℃ and (85 ± 5)% relative humidity for at least 4H. Remove the mask from the environmental box for testing within 1 minute.
The mask is fixed on the protruding fixture, and 2ml of synthetic blood (surface tension (4.0 ~ 4.4) is fixed at a distance of 305mm × 10-4n / cm) from the casing with inner diameter of 0.84mm, spray it horizontally to the tested mask. The test pressure is 10.7kpa (80 mmHg). Remove the mask and check whether the inner side is transparent. The results shall comply with the provisions of article 4.7 of this standard.
5.7 surface moisture permeability test
The test shall be conducted by the method specified in GB / T 4745, and the results shall comply with Article 4.8 of this standard.
5.8 disinfection and sterilization
The test shall be conducted by the method specified in GB 15980, and the results shall comply with Article 4.9 of this standard.
5.9 ethylene oxide residue
The test shall be conducted according to the method specified in gb15980-1995, and the results shall comply with the provisions of article 4.10 of this standard.
5.10 flame retardancy:
A total of 4 masks should be tested. 2 are temperature pretreated and 2 are not pretreated.
Temperature pretreatment conditions:
a) (70 ± 3) ℃ in air for 24 hours
b) (- 30 ± 3) ℃ in air for 24 hours
After temperature pretreatment, it shall be restored at room temperature for at least 4 hours.
The single burner test shall be carried out according to the following procedures, and the results shall comply with the provisions of 4.11.
Put the mask on the metal head mold, and the linear velocity of the head mold measured at the nose tip is (60 ± 5) mm / s.
The position of the head mold passing through the propane burner is adjustable. The distance between the top of the burner and the lowest part of the mask (when placed directly against the burner) shall be set at (20 ± 2) mm.
Turn the head mold away from the area adjacent to the burner, turn on propane gas, adjust the pressure to 20000 ~ 30000 PA (0.2 bar ~ 0.3 bar) and ignite the gas. Adjust the flame height to (40 ± 4) mm through the needle valve and carefully adjust the air supply pressure. The temperature of the flame shall be (800 ± 50) ℃ measured with a 1.5mm diameter metal isolated thermocouple probe (20 ± 2) mm above the burner tip.
Set the head mold to the moving state and record the effect of the mask passing through the flame at one time.
The test shall be repeated so that all materials outside the mask can be evaluated. Any component shall pass through the flame only once.
5.11 skin irritation
The test shall be conducted according to the method specified in GB / T 16886.10, and the results shall comply with the provisions of article 4.12 of this standard.
5.12 identification and operation instructions
Visual inspection shall comply with the provisions of article 4.13.
instructions
⒍ 1 Identification
⒍ 1.1 the minimum package of respirator shall at least have the following clear and easily recognizable marks. If the package is transparent, the marks shall be visible through the package:
a) Product name;
b) The name and trademark of the manufacturer or supplier;
c) Product form identification;
d) Filter material grade: N95 / n99;
e) Storage life;
f) Description of "please refer to the information provided by the producer";
g) Storage conditions recommended by the manufacturer (at least temperature and humidity conditions);
h) Components to be assembled shall be marked with safety symbols;
i) Disposable use shall have disposable identification;
j) The sterilization method shall be indicated for the repeatedly used.
Note: N95 / N95 is the grade of filter material, and the filtration efficiency of this grade of filter material for non oily particles shall not be less than 95% / 99%.
⒍ 1.2 the packing box shall at least have the following contents or marks:
a) Manufacturer's name, address, telephone number and postal code;
b) Product name;
c) Product executive standard number;
d) Production batch number;
e) Weight;
f) Specification and quantity;
g) Volume;
h) Words and signs such as sunscreen and fear of moisture shall comply with the provisions of GB / T191.
⒍ 2 operating instructions
The instruction manual shall at least be in Chinese.
The instruction manual shall at least give the following contents:
a) Use and use restrictions;
b) The meaning of colored codes;
c) Inspection required before use;
d) Wearing suitability;
e) Method of use;
f) Maintenance (e.g. cleaning, disinfection), if applicable;
g) Storage;
h) The meaning of symbols and / or diagrams used;
i)
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