With the exception of withdrawn OSHA Method 7, withdrawn methods retain the validation status that applied at the time of publication based on OSHA’s then current validation guidelines. The validation data found in these withdrawn methods may still be useful. However, when making a determination regarding fitness for use, or when evaluating measurement uncertainty estimations, support for these methods is limited to the existing data. Any user of withdrawn OSHA methods should evaluate the potential need for additional independent data beyond what currently exists that may be required to validate a specific use.
Regarding Method 7, a determination was made to simply cite the NIOSH methods that formed the basis for the method. This method was never intended to cover analytes not listed in the method, nor other sampling and analysis approaches besides those specified. By reverting to the NIOSH methods in lieu of citing Method 7, we recognize the usefulness of the NIOSH methods, while indicating that OSHA Method 7 was never intended to apply to analytes not listed there, nor to other sampling media, desorption solvents, or other desorption approaches.