Short Contact Times for Disinfectants
At Newline, we work with Manufacturers who comply with Biocidal Products Regulation (BPR) 528/2012 which was implemented to ensure a high level of protection for human health, animal health and the environment. It requires that label claims must be supported by test results from tests appropriate to the area of application.
Test parameters, including temperature, concentration and contact times, reflect practical application conditions.
Our manufacturers also follow European Chemicals Agency (ECHA) guidance, and EN 14885 to ensure that the efficacy of all its disinfectants have been assessed using appropriate and relevant test methods. The numbers and identification of organisms present on a contaminated surface is unknown. Therefore, disinfectants must have a broad spectrum of activity so all of the organisms that may be present are controlled.
Tests that most closely reproduce the practical application conditions should be selected. e.g. for a spray and wipe product EN 16615 is appropriate.
A suspension test will assess the time / concentration required to support a claim, then a surface test verifies the dilutions in real-life tests. As a minimum, both suspension and surface tests need to be performed with bacteria and yeast to support claims for hard surface disinfectants.
The recommended contact time on the label must be realistic and appropriate to the use. For example, a 30 second contact time is realistic and appropriate for an alcoholic hand-rub, but 5 minutes is not appropriate as the product would have evaporated in this time.
If a product is to be used as a final stage disinfectant, without rinsing, then a longer contact time is acceptable, e.g. food processing disinfectants sprayed onto surfaces and left overnight or until the next shift.
A shorter contact time does not necessarily mean one product is better than another. A compromise must be reached between safety and the claims made for a product. Increasing the contact time may mean a lower concentration is effective and is therefore safer to use. Decreasing the contact time may mean a higher concentration is required which is not always desirable e.g. for the health and safety of the user. There may also be other aspects to consider e.g. damage to surfaces or potentially higher levels of residues left on surfaces.
