Inserting a membrane pore filter

EN 13624:2013

Quantitative suspension test for the evaluation of fungicidal and yeasticidal activities of disinfectants intended for use in the medical area.

EN 13624 is a phase 2 step 1 suspension test performed on disinfectants intended for use in the medical area to test the efficacy of the product against fungi and yeasts.

Yeast and fungi occur naturally in the environment. Although many assume both microorganisms are the same, they are not. Yeast is a single-celled microorganism and it reproduces through mitosis. Fungus however, is a multi-celled microorganism that reproduces through spores. Efficacy against yeast is a mandatory requirement according to the European Norms.


Test Conditions

The standard refers to the parameters to be observed when testing products intended for use in the medical area. The parameter includes the test microorganism, test temperature, contact time and interfering substance. 

Refer to the table below for the minimum EN 13624 test conditions.


Test Method


In EN 13624 phase 2 step 1 suspension test, 8 parts of the test product is added to 1-part test microorganism and 1-part interfering substance. The mixture is allowed to interact for the duration of the contact time. One part of the mixture is added to 8 parts of neutralizer and 1-part water for 5 minutes to halt fungicidal or yeasticidal activity. The final mixture is then acquired and incubated for 3 days to allow surviving yeast or fungi (if any) to proliferate. The colony is counted and compared against the original culture size.

Diagram 1: EN 13624 test method


Log Reduction


Log reduction refers to the extent to which a product is capable of reducing the number of microbes. For example, 4-log reduction means the number of microorganisms on a surface has been reduced by 10 000 times. A product that is 99.9% effective against a certain microbe is said to have achieved 3-log reduction against that microbe.

For a product to pass EN 13624, it must be able to achieve 4-log reduction against the respective test microorganisms listed in Table 1. In other words, the product must be able to kill 99.99% of yeasts or fungi while meeting all the other requirements of the European standard.

Difference between test product that pass & fail EN 13624 for A. brasiliensis

Read more about the differences between suspension test and carrier test