Testing the air
Graham Lewis, Corporate Key Accounts Manager – Colorex, from Forbo Flooring Systems, takes a closer look at two key regulatory requirements for air cleanliness in cleanrooms.
Although there is classification and categoris-ation of cleanroom environments by the ISO, until recently there was no standard to determine if a product met these ISO categories. The Fraunhofer Society has been working to change this.
The Fraunhofer Society in Germany is the largest organisation for applied research in Europe. It undertakes applied research of direct utility to private and public enterprises and is of wide benefit to society; as such, the industrial alliance started by Fraunhofer, Cleanroom Suitable Materials (CSM), has developed procedures for determining the suitability of materials for cleanrooms.
The comprehensive tests are carried out in a standardised way and in compliance with relevant national and international norms. The results obtained provide an objective and substantiated basis for comparison and should be referred to when selecting suitable materials for specific production environments and fields of application.
With regard to flooring, there are two key ISO standards. First, the test for Particle Emission by Dynamic Friction and Classification according to ISO 14644-1 is simulated by a PA6 nylon wheel travelling over a given specimen, at three different load forces. This determines the level of particulate contamination emitted during the application, in terms of the detected number and size of any released particles. The results should lie within the permitted values of the Air Cleanliness ISO Class 4, in accordance with ISO 14644-1.
The second significant standard, airborne molecular contamination, or outgassing, is tested using thermo-desorption, gas chromatography or mass spectrometry, which provides a qualitative and quantitative analysis suitable for measuring the emission of VOCs. In particular, the test looks at outgassing of particular substances – amines, organophosphates, siloxanes, phtalates and SVOC – all of which could have a detrimental effect on a cleanroom environment. Industries such as aerospace, microelectronics and pharmaceuticals are particularly sensitive to such airborne contaminants.
The results obtained from these tests aim to provide an objective and substantiated basis for comparison and can be referred to when selecting suitable materials for specific production environments and fields of application.
For more information on Forbo Flooring Systems please visit www.forbo-flooring.co.uk/colorex
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