Disinfectants play an important role in the prevention of spread of infections particularly in medical areas where the risk of spread of infections is very high. Therefore, it is necessary to thoroughly evaluate the efficacy of disinfectants before they are released in the market. EN 14476 standard provides a test method to assess the virucidal activity of disinfectant sprays. It ensures that the products meet the required standards of efficacy and safety.
EN 14476 standard
The EN 14476 is a European standard that provides guidelines for testing the efficacy of disinfectant sprays against viruses. This quantitative suspension test (phase 2, step 1) method provides guidelines on the test conditions including contact time, temperature, and the presence of interfering substances that must be followed during the testing process. The test aims to simulate the real-world conditions to ensure that the disinfectant spray products perform effectively in practical situations.
Scope of EN 14476
The EN 14476 standard is applicable to disinfectant products used in medical settings including surface disinfectants, hand rubs, textile disinfectants and instrument disinfectants.
The importance of EN 14476 testing for Disinfectant Spray Products
It is important to test disinfectants according to EN 14476 because this testing is conducted against a wide range of viruses which ensures that the products have a broad spectrum efficacy. This assurance is important in healthcare settings where the risk of transmission of viral infections is very high.
Key components of EN 14476 testing
Test organisms
EN 14476 involves the testing of disinfectants against a wide variety of viruses including both enveloped and non-enveloped viruses. These include
- Poliovirus
- Adenovirus
- Murine norovirus
- Vaccinia virus (for enveloped viruses)
These organisms are chosen because they represent a range of viruses with different characteristics. Use of these viruses ensures a complete assessment of the efficacy of the disinfectant spray.
Test conditions
Minimum test conditions
- Test temperature: 20°C
- Contact time: 30 seconds to 5 minutes
- Interfering substances: Known amount of organic load to simulate soiling
Modified methods
A modified method of EN 14476 is also available for testing ready-to-use disinfectant products with concentrations higher than 80% and up to 97%. This helps evaluate the virucidal activity of highly concentrated products.
Testing procedure
Preparing test organism suspensions
The test process begins with the preparation of the test organisms suspensions. This step involves culturing the viruses and preparing a specific titre for use in the test.
Preparing product test solutions
Disinfectant solutions are prepared according to the instructions provided by the manufacturers. This includes diluting the product to the concentration intended for use.
Virucidal activity assessment
- Addition of virus suspension – The virus suspension and soil is added to the disinfectant solution.
- Incubation – The mixture is incubated for the specified contact time and temperature.
- Neutralization – The action of the disinfectant is stopped by adding a neutralizing agent.
- Titration – The remaining virus is titrated to determine its concentration.
Cytotoxicity and control tests
The standard includes procedures for assessing the cytotoxicity of the disinfectant solution and the efficiency of the neutralization process. These control tests are important to ensure the validity of the results.
Calculation and interpretation of results
Infectivity titer calculation
The infectivity titer of the virus is calculated using either the TCID50 (Tissue Culture Infectious Dose 50) or PFU (Plaque-Forming Units) method.
Virucidal activity calculation
The concentration of the infectious virus is measured before and after the treatment with the disinfectant to determine the virucidal activity. The disinfectants must exhibit a 4-log reduction (99.99%) in the viral titer to be considered effective for use in medical settings and other relevant industries.
Reporting results
The test report must include detailed information on the test conditions, procedures, and results. This includes:
- Test organism used
- Contact time and temperature
- Interfering substances
- Virucidal activity expressed as log reduction of virus titer
The impacts of EN 14476 testing
Ensures compliance – Manufacturers must ensure that these products are thoroughly tested to demonstrate efficacy and meet the requirements of EN 14476 to be compliant with European regulations.
Improves product credibility – Products that pass EN 14476 testing can be marketed with greater credibility. This assures users that these products are effective against viruses. This is important in healthcare and other settings where controlling infections is of utmost importance.
Address emerging viral threats – Testing against various strains of viruses ensures that the disinfectant products are effective against a broad spectrum of viruses including the emerging threats. Thus EN 14476 helps in protecting public health against emerging viral diseases.
Role of MIS
At Microbe Investigations Switzerland, we specialize in conducting EN 14476 testing to verify the virucidal efficacy of disinfectant sprays. Our team of expert microbiologists utilizes advanced methodologies and state-of-the-art technology to deliver precise and reliable results, ensuring your products meet stringent international standards. Trust MIS to help you validate the effectiveness of your disinfectant sprays and maintain regulatory compliance.
To learn more about our EN 14476 testing services for disinfectant sprays or to schedule a consultation with our specialists, please contact us today.
