BS EN 17126:2018

The EN 17126 is a phase 2 step 1 suspension test aimed at the medical and healthcare industry. The test uses bacterial spores, so it is different from other suspension tests.

The EN 17126 isn’t a mandatory test so you will only need it when making a sporicidal or Clostridium difficile claim. EN 17126 spores are made in a way that ensures they are very hardy so they can be difficult to kill.

The EN 17126 is a suspension test which means it is carried out using a suspension of test organism, interfering substance and test product. The interfering substance and the organism make up 20% of this mix so even a ready to use product is diluted to 80% during the test. If the product is to be prediluted, we increase the percentage of product by 1.25 to account for the dilution. In the EN 17126 there is a clause that states we carry out a modified test that uses a ready to use product at 97% rather than the usual 80%. This is done by concentrating the inoculum and interfering substance.

The EN 17126 allows testing against Bacillus subtilis and Bacillus cereus. If you test against these two you can make a sporicidal claim. There is also the option in the standard to test against Clostridium difficile. This means you can make a claim against Clostridium difficile. When selling into hospitals a Clostridium difficile claim may be important as infections caused by this organism are increasing and can be difficult to treat.

As for all BPR submissions you must have three product concentrations tested. These include the final usage concentration, a concentration that fails the test and then an intermediate which can pass or fail.

The table above shows the test parameters but often the NHS will insist on different conditions. If you are testing for a specific tender, you should check the requirements of this before testing.