Moisture resistant microbial penetration tester

Synthetic blood penetration tester for medical use of molten jet filter material

Synthetic blood penetration tester for medical use of molten jet filter material

Used for the determination of the penetration performance of synthetic blood and other liquid source fluids to evaluate its safety protection performance

I. Applicable standards:

Gb19083-2010: Technical requirements for medical protective melting spraying and filtering materials;

YY 0469-2011: Medical and surgical molten jet filter material;

YY/T0691-2008: Test method for transmittance of medical masks against synthetic blood in protective equipment for infectious Pathogens (fixed volume, horizontal injection);

Third, technical parameters

Test environment: Temperature (21±5)℃;

Relative humidity (85±10)%

Injection distance: (300±10)mm

Nozzle diameter: Φ 0.84 mm, 12.7 mm long

Liquid injection speed: 450cm/s;

550 cm/s;

635 cm/s

Power supply: AC220V 50Hz

PMMA production size: 800mm-460mm-550mm

Iv. Main USES

It is suitable for the determination of the splash-penetration property of synthetic blood from medical melt - jet filter.

It can be used by medical inspection departments, safety inspection departments and scientific research units.

Five, the principle of

The medical mask sample was supported on the test device, and 2mL of synthetic blood was sprayed horizontally from the sleeve with an inner diameter of 0.84mm to the measured melting spray filter material at a distance of 300mm.

Simulate the scene in which the mask is splashed by blood from perforated blood vessels and observe the penetration of synthetic blood on the other side of molten jet filter material.

The liquid injection pressure corresponding to the liquid injection velocity of 450cm/s, 550cm /s and 635cm /s was used to test the medical mask samples.

The test results of each injection velocity were recorded, and the acceptable quality level of the medical mask was limited to 4, corresponding to Zuigao blood pressure.

6. Test steps

1. Hold the handle of the sample clamp on the upper left side of the instrument and pull the sample clamp on the left side.

The sample (the standard requires the sample to be taken out of the pretreatment chamber for testing within 60s) was fixed on the sample clip. If there were folds in the molten jet filter material, the folds were unrolled and fixed on the sample clip to ensure that the target area was a monolayer material and the sample center was used as the test target area.

Close the sample clamp.

2. Press the "Start" button, at this time, a certain amount of synthetic blood (surface tension (0.042±0.002) N/m) will be sprayed along the horizontal direction to the measured molten jet filter material behind the target. At the same time, the time timer will start, and the injection will stop automatically after the set injection time.

After 10s, the buzzer sounded, press the "stop" button, and pay attention to check whether there is synthetic blood on the observation surface of the sample.

3. End of one test.

If further tests are required, repeat steps A-C until all tests are completed.

At the end of the test, the synthetic blood residue in the test tank shall be cleared, and the distilled water shall be replaced to clean the entire pipeline. After the nozzle spouts with clean water, the pure water in the test tank shall be continuously drained.

Close the air compressor outlet valve and turn off the power switch.

Clean the residual liquid dish, clean the working table, and clean the distilled water in the test liquid box.

4. Positioning target test

First, close the outlet valve of the air compressor, connect the air compressor to the power supply, and wait for the air compressor to reach the predetermined pressure.

Cut off the air pressure electromechanical source, close the air source switch, open the outlet valve and pull up the valve head of the filter pressure reducing valve on the left side of the instrument. As indicated by the valve head, the direction of "+" is pressurization, and the direction of "-" is pressure reducing adjustment, so that the pressure gauge of the filter pressure reducing valve shows 0.2mpa.

Install the upper positioning target, make the distance between the back of the positioning target and the molten jet filter sample 10mm, and tighten the positioning screw on the guiding plate at the bottom of the positioning target.

5. Rotate the air source switch on the left side of the instrument to close (vertical is closed), turn on the power switch, press the "Upper test liquid" button, and pay attention to the return pipe above the test liquid box. If the return pipe has test liquid flowing out, press the "Upper test liquid" button immediately.

Liquid loading is finished.

After determining the distance between the nozzle and the mask with a locating ruler (300±10)mm, fix the locating target base with screws.

Turning the instrument on the left side of the gas source switch level (knob), adjust the precision pressure reducing valve at the top of the instrument, follow the instructions of the valve head, "+" direction for pressurization, "-" direction for the reduced pressure adjustment, adjust the pressure gauge pressure reference table 2, will be on the front panel "injection time" timer set to 1 min or longer time, press the "start" key, loosen the nozzle positioning screw, up and down or so adjust the nozzle, take the ejected test flow alignment positioning on the target plate holes center point-blank shaped, tighten the set screw, press the "stop" key.

For test liquids with a density of 1.005g/mL, the relationship between pressure and flow rate of the pressure gauge is shown in Table 2.

Set the "injection time" timer on the panel as 1s, press the "Start" button, stop the injection after the injection for 1s, and use the balance to weigh the mass of the liquid ejected from the nozzle to ensure that the mass of the liquid ejected is within the range given in Table 2.

If it is not within the range, the pressure value can be fine-tuned (refer to 6.2.4 for liquid aiming at the target hole) so that the liquid mass passing through the target hole is within the range given in Table 2.

The relationship between the pressure of the reference pressure gauge and the injection time is shown in Table 3. Under different pressures, the injection time is adjusted so that the volume of liquid that continuously sprays through the target hole for three times is 2mL, and for the test liquid with a density of 1.005g/mL, the mass is 2.01g.

If the volume of liquid ejected from the nozzle (from the place where the sample is placed) is not 2mL, the injection time can be adjusted appropriately to ensure that the volume of liquid passing through the target hole is 2mL.

(Three sets of samples corresponding to three injection speeds of 450cm /s, 550cm /s and 635cm /s shall be prepared for the test. Tests shall be conducted at different injection speeds to evaluate the synthetic blood penetration resistance of the sample.) Then the test shall be carried out according to the following steps.

7. Test steps

Hold the handle of the sample clamp on the upper left of the instrument and pull the sample clamp on the left side.

The sample (the standard requires the sample to be tested within 60s after being taken out of the pretreatment chamber) was fixed on the sample clip. If there were folds in the molten jet filter material, the folds were unrolled and fixed on the sample clip to ensure that the target area was a monolayer material and the sample center was used as the test target area.

Close the sample clamp.

Press the "Start" button, at this time, a certain amount of synthetic blood (surface tension (0.042±0.002) N/m) will be sprayed along the horizontal direction to the measured molten jet filter material behind the target, and the injection will start. At the same time, the time relay will start timing. After the set injection time, the automatic injection of the instrument will stop.

After 10s, the buzzer will sound, press the "Stop" button to open the sample holder.

Under proper lighting conditions, check the presence of synthetic blood on the observation surface of the sample.

The end of an experiment.

If further tests are required, repeat steps A-C until all tests are completed.

At the end of the test, the synthetic blood residue in the test tank shall be cleared, and the distilled water shall be replaced to clean the entire pipeline. After the nozzle spouts with clean water, the pure water in the test tank shall be continuously drained.

Close the air compressor outlet valve and turn off the power switch.

Clean the residual liquid dish, clean the working table, and clean the distilled water in the test liquid box.