YY/T 0698.2-2022Packaging materials for final sterilized medical devices - Part 2: Requirements and test methods for sterilized packaging materials (English PDF)

4.1 General rule

For the materials for preformed sterile barrier systems and sterile barrier systems, the requirements of GB/T 19633.1 are applicable.

Only the operational performances and test methods of the materials included are provided in this document, the general requirements specified in GB/T 19633.1 are not as required.

Note: See Appendix B, GB/T 23329, ISO 9073-9, and GB/T 8942 for the test method.

4.2.2 Specific requirements

4.2.2.1 Flat paper wrapping materials

4.2.2.1.1 When tested according to GB/T 455, the tearing strength of the wrapping material along the machine direction and in the transverse direction shall not be less than 500 mN. See GB/T 450 for the determination of machine direction and transverse direction.

4.2.2.1.2 When tested according to the Bendtsen method specified in GB/T 458, under the air pressure of 1.47 kPa, the air permeability of the wrapping material shall not be less than 1.7 µm/(Pa · s).

4.2.2.1.3 When tested according to GB/T 454, the bursting strength of the wrapping material shall not be less than 110 kPa.

4.2.2.1.4 When tested with an immersion of 10 min according to GB/T 465.1, the wet bursting strength of the wrapping material shall not be less than 35 kPa.

4.2.2.1.5 When tested according to Appendix A, the hydrophobicity of the wrapping material shall be such that the penetration time is not less than 20 s.

4.2.2.1.6 When tested according to Appendix C, the average pore diameter of 10 samples shall not exceed 35 µm, and the maximum value shall not exceed 50 µm.

4.2.2.1.7 When tested according to GB/T 12914, the tensile strength of the wrapping material shall not be less than 1.33 kN/m along the machine direction, and not less than

0.67 kN/m in the transverse direction.

4.2.2.1.8 When tested according to GB/T 465.2, the wet tensile strength of the wrapping material shall not be less than 0.33 kN/m along the machine direction, and not less than

0.27 kN/m in the transverse direction.

4.2.2.1.9 When tested with a test time of 60 s (Cobb method) according to GB/T 1540, the water absorption (Cobb value) of each side of the paper shall not exceed 20 g/m2.

4.2.2.2 Crepe paper wrapping material

4.2.2.2.1 The wrapping material of crepe paper shall be wrinkled to improve its softness.

4.2.2.2.2 When tested according to GB/T 12914, the elongation at break of the wrapping material shall not be less than 10% along the machine direction and not less than 2% in the transverse direction.

4.2.2.2.3 When tested according to Appendix A, the hydrophobicity of the wrapping material shall be such that the penetration time is not less than 20 s.

4.2.2.2.4 When tested according to Appendix C, the average pore diameter of 10 samples shall not exceed 35 µm, and the maximum value shall not exceed 50 µm.

4.2.2.2.5 When tested according to GB/T 12914, the tensile strength of the wrapping material shall not be less than 1.33 kN/m along the machine direction, and not less than

0.67 kN/m in the transverse direction.

4.2.2.2.6 When tested according to GB/T 465.2, the wet tensile strength of the wrapping material shall not be less than 0.33 kN/m along the machine direction, and not less than

0.27 kN/m in the transverse direction.

4.2.2.3 Nonwoven wrapping materials

Note: The nonwovens used for sterile barrier systems mentioned in this section can be understood they are made of textile fibers and/or nonwoven fibers.

4.2.2.3.1 When tested according to GB/T 455, the intrinsic tearing strength of the nonwoven wrapping material shall not be less than 750 mN along the machine direction, and not less than 1000 mN in the transverse direction.

4.2.2.3.2 When tested according to GB/T 454, the bursting strength of the wrapping material shall not be less than 130 kPa.

4.2.2.3.3 When tested with a water immersion of 10 min according to GB/T 465.1, the wet bursting strength of the nonwoven shall not be less than 90 kPa.

4.2.2.3.4 When tested according to GB/T 12914, the elongation at break of the nonwoven shall not be less than 5% along the machine direction and not less than 7% in the transverse direction.

4.2.2.3.5 When tested according to GB/T 12914, the tensile strength of the nonwoven wrapping material shall not be less than 1.00 kN/m along the machine direction, and not less than 0.65 kN/m in the transverse direction.

4.2.2.3.6 When tested according to GB/T 465.2, the wet tensile strength of the nonwoven wrapping material shall not be less than 0.75 kN/m along the machine direction, and not less than 0.50 kN/m in the transverse direction.

4.2.2.3.7 The test results of the waterproof performance of nonwoven wrapping materials shall be determined and recorded according to the hydrostatic pressure method in GB/T 4744.

4.2.2.4 Textile wrapping materials

Appendix A (Normative)

Test method for determining hydrophobicity

A.1 Instrument

A.1.1 Ultraviolet light source (UV-A, 315 nm~390 nm) and ultraviolet radiation meter.

A.1.2 Flat plate, about 200 mm×150 mm×15 mm.

A.1.3 Dryer.

A.1.4 Stopwatch.

A.1.5 A powder-dusting instrument that has a sieve with a nominal aperture of 0.125 mm~0.150 mm at one end and a closed end at the other end.

A.2 Reagents

The dry indicator powder shall be prepared as follows:

Crush 20 g of sucrose and sift it through a sieve with a nominal aperture of 0.063 mm~0.075 mm. Place the sifted sucrose above the silica gel in a desiccator or dry it in an oven at 105 °C to 110 °C. Mix 10 g of dried sucrose with 10 mg of sodium fluorescein, and sift the mixed powder through a sieve with a nominal aperture of 0.063 mm~0.075 mm 5 times. Finally, transfer the dry indicator powder to the powder-dusting instrument.

The dry indicator powder in the powder-dusting instrument shall be stored in a desiccator or in an oven at 105 °C to 110 °C.

A.3 Steps

Take 10 conditioned paper specimens, each 60 mm×60 mm, and divide them into two groups, 5 specimens for each group. For one group, let the “wrapping side” up, and for the other group, let the exposed side up. Fold each specimen at right angles to a height of 10 mm along both sides. Pour the purified water into the flat plate at the conditioning temperature, and the water depth is 10 mm. Turn on the UV lamp to make it reach the maximum brightness, and adjust the distance of the lamp to make the illuminance of the water surface in the plate be (300±20) µW/cm2. Sprinkle a thin layer of dry indicator powder on one specimen. Float the specimen on the water surface under the ultraviolet lamp, and record the time when fluorescence appears. Repeat the steps for the other 9 specimens.

Appendix C (Normative)

Test method for determining aperture

C.1 Principle

When the air is forced to pass through the pores of the material wetted by a solution, the required pressure is observed. The pressure and the known surface tension of the solution are used to estimate the size of the pores in the material. The estimated value is the equivalent aperture of the material.

C.2 Test solution

The test solution used should be able to completely wet the paper, and have low solvent solubility for water-blocking materials; it shall not expand the fibers, and have constant surface tension; it shall be non-toxic, have no foam, and have a low ignition point and a reasonable price.

Note: Absolute ethanol reagent is considered suitable.

C.3 Instrument

C.3.1 The test instrument is shown in Figure C.1:

a) Test head “1”: a cylindrical container made of a suitable material (such as brass), above which the specimen “a” can be clamped by a ring clamp “b” and a bolt “c”.

Seal the specimen with a synthetic rubber gasket “d” with an inner diameter of

50 mm;

b) Pressure measuring device;

c) Switch for air flowing to the test head;

d) Flow regulating valve for increasing the pressure in the test head “1”;

e) Switch for air flowing to the pressure measuring device;

f) A gas storage cylinder with a capacity of about 2.5 L, connected to the test head

“1”, to ensure the air flow rate necessary to maintain the pressure rise to overcome the airflow loss through the material;

g) Air supply.

C.3.2 Carry out the test with the instrument shown in Figure C.1:

3) There is no leakage of the test solution during the test;

4) The sample in the clamp does not slide during the test.

Note: A clamp of elastic material shall be used to prevent leakage of the test solution. A suitable synthetic rubber shall be used to obtain suitable contact conditions.

b) The rising rate of air pressure shall be 2 kPa/min~2.5 kPa/min (200 mmH2O/min~250 mmH2O/min)2).

c) The pressure measuring device connected to the test head shall be read in kPa (or mmH2O).

d) The pressure measuring device shall have an appropriate measuring range.

Note: For most materials, a pressure measuring device with a range of 6 kPa (600 mmH2O) is suitable.

For the measurement of airtight materials, such as waterproof materials, clean clothes, surgical gowns, and surgical drapes, it is recommended to use a pressure measuring device with a range of 10 kPa.

C.4 Preparation of specimens

The material shall be disposed of as little as possible, with no folding, ironing, or other handling other than conditioning the specimens. Cut specimens from different locations on the material to make them as representative as possible. Specimens shall be cut into shapes for easy handling and clamping.

Note: For most instruments, it is more convenient to cut the specimen into a square of 75 mm×75 mm.

Unless otherwise specified, cut 10 specimens from the test material.

C.5 Steps

C.5.1 Carry out the test under the test conditions specified in GB/T 10739.

C.5.2 Use any suitable method to measure the surface tension of the test solution, and the accuracy shall be 0.5 mN/m.

Note: Under standard atmospheric pressure, the surface tension of absolute ethanol reagents is generally

22 mN/m~24 mN/m, and the temperature correction coefficient is: -0.005 mN/(m · K).

Wilhelmy method, stalagmometer method, single capillary method, and double capillary method can fulfill the measurement of surface tension.

C.5.3 Soak the conditioned specimen about 15 mm (deep) below the surface of the test

2) 1 mmH2O=9.80655 Pa.

Note 1: When the relative density of water at standard atmospheric temperature is taken as 1 mg/mm3, the error introduced to the test and the variability of the test results are relatively small.

Note 2: Similarly, although it is known that the g value in different regions varies by 0.5%, when it is assumed to be a constant value of 9810 mm/s2, the error introduced and the variability of the test results are relatively small.

C.6.2 Derivation of the calculation formula of the equivalent pore radius

For a cylindrical pipe, the pressure required to make the liquid pass through it can be calculated according to the formula (C.3):

where:

T --- The value of the surface tension of the liquid, the unit is Newton per meter (N/m);

Q --- The value of the contact angle of the interface between the liquid and the solid, in degrees Celsius (°);

r --- The value of the radius of the lumen, in meters (m).

This is the Laplace equation.

The contact angle is very difficult to be measured, so a liquid is used to completely wet the material such that cosQ=1, then the formula becomes as follows:

This pressure is usually measured in millimeters of water, so a differential pressure gauge or a pressure measuring device calibrated in millimeters of water is used.

Therefore:

where:

Pb --- The value of the height of the water column, the unit is the millimeter of water (mmH2O);

rho --- The value of the density of water, in milligrams per cubic millimeter (mg/mm3);

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