Moisture resistant microbial penetration tester

Dry microbial penetration tester for medical protective clothing

A large number of examples have shown that bacteria can penetrate shielding materials with dry organic or inorganic particles, such as skin scraps or clean clothes carrying bacteria, and particles carrying bacteria penetrating packaging materials during storage period. This instrument can be used to measure the penetration of bacteria on dry particles within the size range of human skin

1. Testing principle of medical protective clothing dry state microbial penetration tester

The test is carried out on the test pieces fixed on a container respectively. Among these containers, 5 containers with Bacillus subtilis talc and one container with uninfected talc were used as control. Insert a dish at the bottom of each container close to the bottom of the specimen.

The equipment supporting the container is vibrated by a gas ball oscillator. All talc powder penetrating the test piece falls onto the Petri dish, and the Petri dish is taken out and cultured.

Count the growing colonies.

technical specifications

1. Test chamber: black inner wall, volume: 0.5m3, built-in fan and lamp;

2. Instrument air source: 0.8MPa compressed air;

3. Noise: About 90dB;

4. Touch screen operation;

5. Instrument size: 1000mm ′ 690mm ′ 1390mm;

6. Instrument weight: 85kg

7. Power supply: 220 v.

Configuration list

The instrument should be carefully unpacked and checked. For any damage and loss of the instrument, please contact our customer service department.

When you open the package, please check the following materials (subject to the actual packing list)

1. One main engine;

2. 8 sets of test boxes;

3. One power line;

4. One copy of instruction manual

5. Optional accessories:

Air tank

2. Test standard

The dry microbial penetration tester tests samples according to ISO 22612 and YY / T 5056.5 test standards.

3. Composition and use of the instrument

The instrument is completed in strict accordance with the standard drawings, which fully meets and can realize the test content required by the standard.

The instrument consists of:

(1) Pneumatic ball oscillator: the external gas source passes through the pneumatic ball oscillator. After corresponding adjustment and correction, the vibration frequency is maintained at the target frequency. It can produce 20800 vibrations per minute with a force of 650n.

(2) Compressed air flowmeter: it is mainly used to measure the air flow which produces 20800 (347hz) vibration frequency per minute.

(3) Test vessel: the instrument has 6 stainless steel test vessels with metal piston on the top. The metal piston can be inserted 10 mm below the cover through the central hole on the cover, and the test piece is not relaxed after insertion. At the same time, the attachment at the bottom of each container has a slit which is used to insert the culture dish.

(4) Marble slab: 400mm * 400mm area and 10mm thick marble are used as the operation platform of the whole instrument.

(5) Fixed plate: a stainless steel plate with 6 holes, which is fixed on the stone plate with a clamp to fix and install the test vessel

(6) Rubber support: with 4 rubber supports, it is used to adjust the level, fix the position of the instrument, and prevent movement.

test

1. Analysis of test steps:

The test is carried out on the test pieces which are respectively fixed on a container. Among these containers, 5 containers carrying Bacillus subtilis talcum powder were used as the test group, and 1 container with uninfected talc powder was used as control. Insert a dish at the bottom of each container close to the bottom of the specimen.

All of them were put into the culture dish, and all of them were supported by the shaker.

Count the number of colonies growing.

2. Equipment commissioning:

Ensure that the dry microbial penetration tester is operational.

(1) Level adjustment

According to the level gauge, adjust the 4 rubber supports to make the instrument in horizontal position.

(2) Adjusting the frequency of gas ball oscillator

By adjusting the gas ball oscillator, it can reach the vibration frequency of 20800 times per minute.

3. Sample preparation:

(1) Cut 12 pieces to be tested

The size of 12 samples is 200 mm × 200 mm.

(2) Sterilization treatment

Sterilize the cut samples and test containers.

(3) Fixed test vessel

The test vessel is fixed on the fixed plate by rubber ring, so that it is closely connected with the fixed plate, and the bottom is against the stone plate.

(4) Talc preparation

The talc powder containing AATCC 9372 Bacillus subtilis spores should be prepared with a concentration of about 108cfu / g. the preparation process is referred to YY / T 5056.5-2009.

4. Start the test.

Take out the test piece by aseptic operation and put it on the mouth of each test container.

The cover is fixed to the container by pushing down on the piston so that the test piece is held at a controlled degree of relaxation.

Remove the piston. 0.5 g ± 0.1 g of bacteria contaminated talc was added to the test piece through the piston port, and the sixth container as the control was added with uninfected talc. Seal the piston port with film.

Each container is covered with a small plastic bag.

The Petri dish is inserted through a slit at the bottom of each container. Close the slit with adhesive tape.

The vibration frequency was 20800 times per minute for 30 minutes.

Remove plastic bags and adhesive tape.

The cover of the culture dish was inserted through the slit, and the culture dish was taken out and cultured at 35 ℃ for 24 h.

Count the colonies formed. The effective sample should be the reference plate reading 0. Otherwise, it indicates that there is external pollution and the test should be stopped.

Repeat the above steps.

Zui test 2 groups less, 10 valid results