MEDICAL MASK – PART 1: COMMON MEDICAL FACEBOOK
Medical face mask – Part 1: Normal medical face mask
1. Scope of application
This standard applies to medical masks (sterilized and non-sterile) used in medical facilities.
The following referenced documents are essential for the application of this standard. For dated references, the cited version applies. For undated referenced documents, the latest version, including amendments and supplements (if any), applies.
TCVN 3154:1979 Personal protective equipment -Method of determining the market (field of view)
TCVN 7312:2003 Personal protective equipment for respiratory organs – Masks with dust filters
3. Technical requirements
– the mask must not cause skin allergies for the wearer;
– the surface of the mask must be clean, free of lint tips and free from defects in appearance;
– straps are sewn securely at the four corners of the mask;
– The edges of the mask must hug the wearer's face tightly.
3.2.1. Medical masks include the following parts:
– layers of fabric: there may be 2 to 4 layers of non-woven fabric, flat, corrugated;
– microfiltration layer;
– nose splints;
3.2.2. Style, size
The size design is not required but must ensure that the nose and mouth are covered.
3.3. Requirements for materials
3.3.1. Fabric layer: using non-absorbent non-woven fabric, weight 14 g/m2¸ 40 g/m2, color: white or other color.
3.3.2. Air-permeable microfiltration layer is waterproof.
3.3.3. Nasal splint: easy to adjust plastic or metal, effectively clamping the mask on the bridge of the nose.
3.3.4. Strap: Use an elastic band, for example, an elastic band, making it easy to put on and take off the mask.
3.4. Technical specifications of masks
Medical masks must meet the technical criteria specified in Table 1.
Table 1 – Technical specifications of masks
|1. Filter efficiency for oil mist in air blowing mode 30 L/min, %, not less than||90|
|2. Respiratory resistance (DP), in air blowing mode 30 L/min, mmH2O, no more than||9|
|3. Field of view limit, %, no more than||6|
|4. Mass, g, not more than||10|
3.5. Permissible limits of heavy metal elements in nonwovens
Permissible limits of heavy metal elements in nonwovens are specified in Table 2.
Table 2 – Permissible limits of heavy metal elements in nonwovens
|Principleoh||Gender permission period, not greater than mg/kg of product|
4. Test method
4.1.Structural inspection, material requirements
Inspect the structure, requirements for materials with the naked eye.
4.2. Check filter performance for oil mist
Check filter efficiency for oil mist according to TCVN 7312:2003, Article 6.3.
4.3. Check respiratory resistance
Check the respiratory resistance according to TCVN 7312:2003, Article 6.4.
4.4. Check field of view
Check the field of view limit according to TCVN 3154-1979.
4.5.Check the volume
Check the mass according to TCVN 7312:2003, Article 6.6.
4.6. Determination of allowable limits for heavy metal elements in nonwovens
Dissolve heavy metals in fabric samples with hydrochloric acid. Determination of heavy metal elements on an atomic absorption spectrometer.
– atomic absorption spectrometer;
– pH meter, accuracy ± 0.1 pH unit.
184.108.40.206. Chemicals, reagents
Analytical reagents use only pure chemicals and certified standards.
220.127.116.11.1. Hydrochloric acid, 0.07 mol/l solution;
18.104.22.168.2. Hydrochloric acid, 2.0 mol/l solution;
22.214.171.124.3. Tricloethane no acid or other suitable solution;
126.96.36.199.4. Reference Materials of the elements arsenic (As), lead (Pb), mercury (Hg), antimony (Sb) and cadmium (Cd).
188.8.131.52. How to proceed?
– mix 5 g of the prepared test sample with 250 g of 0,07 mol/l hydrochloric acid solution and shake for 1 min.
– check the acidity of the mixture. If the pH is greater than 1.5, shake and add 2.0 mol/l hydrochloric acid drop by drop until the pH is less than or equal to 1.5. Make up to 250 ml.
– the mixture is shaken continuously then allowed to stand for 1 h at a temperature of 37 °C ± 2 °C.
NOTE The mixture should not be exposed to light.
Allow the mixture to cool and then filter it through a blue-band filter. Take the filtrate for the determination of heavy metal elements on an atomic absorption spectrometer.
5. Packaging and labeling
The quantity and packaging of masks are tailored to specific needs.
The label must be affixed on the cardboard box with the following minimum information:
- Product's name,
– reference to this standard,
– the name and address of the manufacturer,
- manufacture date expiry date,
– KCS check mark,
- User manual.