1.1 The method provides a protocol for capturing, extracting and quantifying the adenosine triphosphate (ATP) content associated with microorganisms found in water-miscible metalworking fluids (MWF).

1.2 The ATP is measured using a bioluminescence enzyme assay, whereby light is generated in amounts proportional to the concentration of ATP in the samples. The light is produced and measured quantitatively as relative light units (RLU) which are converted by comparison with an ATP standard and computation to pg ATP/mL.

1.3 This method is equally suitable for use in the laboratory or field.

1.4 The method detects ATP concentrations in the range of 4.0 pg ATP/mL to 400,000 pg ATP/mL.

1.5 Providing interferences can be overcome, bioluminescence is a reliable and proven method for qualifying and quantifying ATP. The method does not differentiate between ATP from different sources, for example, from different types of microorganisms, such as bacteria and fungi.

1.6 The values stated in SI are to be regarded as standard.

1.7 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 and health practices and determine the applicability of regulatory limitations prior to use.