GB/T 15981-2021Evaluating method for the efficacy of sterilization for disinfection equipment (English PDF)

3.1 D value

Under the set exposure conditions, the time required to kill 90% of the total number of specific test microorganisms.

3.2 Carrier

Support for test microorganisms.

3.4 Process challenge device; PCD

A specially designed device to simulate the sterilization of articles, resistant to a specific sterilization process, and used to evaluate the effectiveness of the sterilization process.

4 Identification test for efficacy of sterilization for disinfection equipment 4.1 Identification test for efficacy of sterilization for pressure steam sterilizer

4.1.2 Test steps

The test steps are as follows.

4.1.3 Evaluation regulations

4.1.3.1 To determine that the efficacy of sterilization of the sterilizer is qualified, it must meet the requirements at the same time. The color of the positive control medium turns yellow for each test. The negative control medium color does not change. The recovered bacteria volume of the control bacteria tablets is >=1 x 10^5 CFU/tablet. The color of the test group remained unchanged.

4.1.3.2 When self-contained biological indicators are used for evaluation, the results are determined according to the instruction manual.

4.1.4 Precautions

4.2.2 Test steps

The test steps are as follows.

4.2.4 Precautions

4.2.4.1 Strictly abide by aseptic technique regulations.

4.2.4.2 The test shall be carried out under full load conditions.

4.3.2 Test steps

The test steps are as follows.

4.3.3 Evaluation regulations

4.3.3.1 To determine the sterilization effect of the sterilizer is qualified, it must meet the following requirements. The amount of recovered bacteria in the control group shall be greater than or equal to 1 x 10^6 CFU/tablet. There is bacterial growth in the positive control group. There is aseptic growth in the negative control group. All the test groups are aseptically grown.

4.3.4 Precautions

4.3.4.1 Ethylene oxide is flammable, explosive and toxic. To ensure the safety of the test, the operators and test personnel shall be familiar with the performance of ethylene oxide and the operating procedures of the equipment.

4.3.4.2 The working environment shall be well ventilated. The maximum allowable concentration of ethylene oxide in the air at the work site is 2mg/m3.If a person inhales too much ethylene oxide gas, it will cause poisoning symptoms. Severe cases can cause pulmonary edema. If symptoms of poisoning appear, leave the scene immediately and rest in a well-ventilated place. Mild cases breathe fresh air until symptoms clear up.

Severe cases shall be sent to hospital for treatment in time.

4.4.2 Test steps

The test steps are as follows.

4.4.3 Evaluation regulations

4.4.3.1 To determine that the sterilization effect of the sterilizer is qualified, it must meet the requirements at the same time. The amount of testing recovered bacteria of the bacterial count control group in each test is 1 x 10^6 CFU/tablet~5 x 10^6 CFU/tablet. There is bacterial growth in the positive control group. There is aseptic growth in the negative control group. There is aseptic growth in the test group.

4.5.1 Test equipment

4.5.1.1 Test contamination carrier. Bacillus stearothermophilus (ATCC 7953 or SSI K31) spores, with qualified resistance identification. The contamination carrier is a stainless-steel needle with a diameter of <=0.4mm.

4.5.1.2 Reagents. Phosphate buffered saline (PBS, see A.1); tryptone soy agar medium (TSA, see A.3); bromocresol purple peptone medium (see A.4).

4.5.1.4 Fully loaded items. The items specified in the instruction manual.

4.5.1.3 Simulated medical device lumen

4.5.2 Test steps

The test steps are as follows.

4.5.4 Precautions

4.5.4.1 Items must be placed in compliance with the regulations. Sterilized items shall be clean and dry.

4.5.4.2 If the hydrogen peroxide gas plasma sterilizer has multiple sterilization programs, each sterilization program shall be verified separately.

4.5.4.3 The identification of the efficacy of sterilization of the hydrogen peroxide gas sterilizer is carried out with reference to the test method in 4.5.