Research project makes it possible continuously to monitor hygiene status
In future, it will be possible to test the hygiene status in laundries directly on site using a newly developed quick detection method. Image: Hohenstein Institutes
The Hohenstein Institute for Textile Innovation (HIT) in Bönnigheim, Germany has developed a quick detection method for checking on site the microbiological water quality of process water. HIT says the method makes it possible to evaluate the quality of process water within a couple of hours.
The detection method was designed as part of a research project (AIF-No.16067N/1) and tested for its practicality.
The quality and test specifications for professional textile services, according to RAL-GZ 992, require the continuous monitoring and documentation of the hygiene status of the processed textiles and the quality of the process water, which is stipulated using microbiological standards. Regular checks are normally carried out on the bacterial count of the process water by external specialised laboratories, which incurs costs and is time consuming.
Left: Result of the Hohenstein quick detection method on microbiologically pure water Right: Discoloration of the quick detection sample due to a high level of bacterial contamination. Image: Hohenstein Institutes
The Hohenstein quick detection method is based on the detection of antibodies, similar to that used for pregnancy tests, and optimised for press water bacteria. Pseudomonads, faeces germs and other bacteria found in process water can be reliably identified to a detection limit of 103 bacteria per millilitre. The analysis and evaluation of the water quality is carried out using a simple colour reaction.
The new detection method has been extensively tested in practical situations at selected laundries. The results correlate with conventional bacterial analyses as carried out in specialised laboratories and are compliant with the specifications of RAL-GZ 992.
The quick bacteria detection method can be carried out independently without the need to buy additional equipment. The test can be carried out and evaluated by laundry staff in just a few steps. Within just a few hours, the test result can be read and the labour requirements involved in implementing the system are low.
The research project was funded through the Association of Industrial Research Organisations (AiF) within the programme promoting the Industrielle Gemeinschaftsforschung und -Entwicklung (IGF) by the German Federal Ministry of Economics and Technology.