ASTM E3180-18

5.1 Biofilm characteristics such as thickness, matrix architecture, and population are dependent on factors such as shear and nutrient availability and composition. Additionally, sporulation can occur within biofilms, including those formed by 1.1 This test method specifies the operational parameters required to grow and quantify a Bacillus subtilis biofilm comprised of vegetative cells and endospores (spores) using the colony biofilm method (CBM).1.2 This test method utilizes a modified CBM to grow the biofilm. The CBM uses a semipermeable membrane on an agar plate as the biofilm growth surface and nutrient source.1.3 This test method describes how to sample and analyze the biofilm for vegetative cells and spores. Biofilm population is expressed as total colony forming units (CFU) and spores per membrane.

1.4 Basic microbiology training is required to perform this test method.

1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.