The en 1276 test is a specified standard test for suspensions to determine whether chemical disinfectants have bactericidal activity. We are manufacturing some antimicrobial products to control and combat certain pathogenic microorganisms. The EN 1276 standard applies to food, industrial, domestic and institutional products, except for areas and situations where sterilization is specified, medical, and does not include products used on living tissue except hand hygiene (e.g. alcohol gel) in food, industrial, domestic and institutional areas.
Table of Contents
- A quantitative suspension test is used for evaluating the bactericidal activity of chemical disinfectants in the food processing, industrial, domestic, and community industries.
- We are using microorganisms to challenge the product.
- We are exposing the microorganisms to the test solution under controlled conditions.
- Determine the number of live bacteria and calculate the decrease in viability.
For assessing the antimicrobial efficacy of surface disinfectants or measuring the cleanliness and safety of materials or surfaces you can find different types of methods. You can also provide expertise to identify these two testing approaches:
- JIS Z 2801: Antimicrobial Tests of Plastics and Materials – “Antimicrobial Products – Antimicrobial Activity and Efficacy Tests”
- ISO standard 22196: Antimicrobial testing of plastics and materials – “Plastics – Measurement of antibacterial activity on plastic surfaces”.
We are using this test to disinfect the food, industrial, domestic and institutional areas, including test microorganisms. You can also include the test temperature, contact time, and interference.
Microorganism testing is mandatory for testing to determine antimicrobial activity. We are assuming Compulsive organisms to be representatives of all microorganisms in their group.
We have to test the test temperature that is also known as the testing temperature. The disinfectants are less effective at low temperatures compared to higher temperatures. The contact time is defined as the minimum amount of time a product has to come into contact with microorganisms for the product to be effective.
The disturbances are substances used in tests to simulate potential contaminants that co-exist with microorganisms in a natural environment.
For the suspension test, you can take 8 parts of the test product added to 1 part of the test microorganism and 1 part of the disturbance. We are leaving the mixture some time to interact at the time of contact. We have to add one aspect of the mixture to 8 parts neutralization agent and 1 part water for 5 minutes to stop the bactericidal activity. We will obtain the final mix and incubate it for two days to allow surviving bacteria (if any) to reproduce. Count the number of bacteria and compare them to the original culture size.
Reduce the log:
Log reduction refers to the extent to which a product can reduce the microbial count. For example, a 4 log reduction means that the microbial count on a surface is 10,000 times lower. A product that is 99.9% effective against certain microorganisms that we have to reduce. The three records compared to that microorganism.
For a product to pass theen 1276 test, it must achieve a 5-log reduction relative to the test microorganisms in the specified order. In the European standard, the test passed product can kill 99.999% of bacteria while meeting all other requirements of the product.
Step by step instruction for EN 1276 test:
You can follow simple steps for the en 1276 test. The steps are here,
- Preparing the sample: First, you need to prepare the sample for the EN 1276 test. You can take the test tube and take 1 ml of interfering substance and test suspension. We have to mix the mixture well for 2 minutes.
- Adding customer sample: You can add 8 ml of customer sample to the test tube in the mixed sample.
- Incubation: You need to allow the sample for incubation at a specified temperature and time.
- Neutralization: For neutralization, you can take one more test tube. After the contact time, you can add 1 ml from test tube A to test tube B. For the neutralization it will take 5 minutes after that you can add some water to test tube B.
- Process: Next, you can take two agar plates separately. You need to add a 1 ml sample from test tube B to the agar plates. You can leave it to incubate. After some time you can see the results in the agar plates.
EN 1277 Quantitative suspension test:
The en 1276 test is one of the best tests for the quantitative suspension tests that use the same principles of the EN 1650 test. You can consider specific environmental parameters such as water hardness and organic impurities. All of which may affect the effectiveness of disinfectants under operating conditions. We have done the test under clean or Dirty conditions using 0.3g/l and 3.0g/l sterile-filtered solutions of Bovine Serum Albumin (BSA), respectively, as disturbances. BS EN 1276 offers two methods for assessing bactericidal activity, where possible.
The method of neutralization with dilution should be used, but for products that do not respond to neutralization, Membrane filtration is used. We have to carry out the audit in parallel with the test. These additional controls are vital features of quantitative suspension testing and are performed at three levels. They are given by,
- Disinfectant neutralization monitoring determines the effectiveness of neutralization agents and is especially important when getting artificial results. It is an exaggeration of the product’s efficacy if the neutralizer does not effectively neutralize the disinfectant activity.
- Neutral toxicity monitoring assesses the toxicity of the neutralizer to organisms.
- Verify the experimental conditions to ensure that the testing conditions do not adversely affect the organisms.
In the method of neutralization with dilution, Bacterial suspensions are added to the BSA solution in equal amounts. Then add disinfectant. We have to neutralize them when the specified touch time has passed, Disinfection activities. We are distributing the solutions using standard microbiological techniques, and the results were compared with the original bacterial suspensions.
You can also follow the same method for the membrane filtration method in the same manner until the contact time expires. At this point, we are transferring a fraction of the test mixture to the sterile diluents contained in the filter. After filtration and washing, we are transferring the membranes to Tryptone Soy agar plates for incubation and enumeration.
The life specified in EN 1650 EN 13704 is a quantitative suspension test for sporicidal activity assessment, which is assessed using the suspension of Bacillus subtilis spores. We are checking ATCC 6633 similarly. Just like any other suspension test. However, only “clean conditions” and a 60 min exposure time are generally used.
In standards, we are checking spores killing activity as the ability of the product to produce at least a 3 log reduction in the number of bacterial spores. It belongs to the test strain of B.subtilis. The acceptance criteria for the fungicide method are less stringent than those tested for other suspensions.
It is almost impossible to achieve a 60 minute exposure time due to the amount of air change. This type of test can offer a reliable method for assessing the performance of disinfectant products under laboratory conditions. But like many microbiological methods, reproduction can be problematic. It has been shown that using standardized BSA improves reproducibility.